MICROCHIP PIC18C801

PIC18C601/801
High-Performance ROM-less Microcontrollers
with External Memory Bus
High Performance RISC CPU:
Advanced Analog Features:
• C compiler optimized architecture instruction set
• Linear program memory addressing up to 2 Mbytes
• Linear data memory addressing to 4 Kbytes
• 10-bit Analog-to-Digital Converter module (A/D)
with:
- Fast sampling rate
- Conversion available during SLEEP
- DNL = ±1 LSb, INL = ±1 LSb
- Up to 12 channels available
• Programmable Low Voltage Detection (LVD)
module
- Supports interrupt on Low Voltage Detection
External Program Memory
On-Chip
Device
PIC18C601
PIC18C801
Maximum
Addressing
(bytes)
Maximum
Single Word
Instructions
256K
2M
128K
1M
On-Chip
RAM (bytes)
1.5K
1.5K
• Up to 160 ns instruction cycle:
- DC - 25 MHz clock input
- 4 MHz - 6 MHz clock input with PLL active
• 16-bit wide instructions, 8-bit wide data path
• Priority levels for interrupts
• 8 x 8 Single Cycle Hardware Multiplier
Peripheral Features:
•
•
•
•
•
•
•
•
•
•
•
High current sink/source 25 mA/25 mA
Up to 47 I/O pins with individual direction control
Three external interrupt pins
Timer0 module: 8-bit/16-bit timer/counter with
8-bit programmable prescaler
Timer1 module: 16-bit timer/counter (time-base for
CCP)
Timer2 module: 8-bit timer/counter with 8-bit
period register
Timer3 module: 16-bit timer/counter
Secondary oscillator clock option - Timer1/Timer3
Two Capture/Compare/PWM (CCP) modules
CCP pins can be configured as:
- Capture input: 16-bit, max. resolution 10 ns
- Compare is 16-bit, max. resolution 160 ns (TCY)
- PWM output: PWM resolution is 1- to 10-bit
Max. PWM freq. @:
8-bit resolution = 99 kHz
10-bit resolution = 24.4 kHz
Master Synchronous Serial Port (MSSP) with two
modes of operation:
- 3-wire SPI™ (Supports all 4 SPI modes)
- I2C™ Master and Slave mode
Addressable USART module: Supports Interrupt
on Address bit
 2001 Microchip Technology Inc.
Special Microcontroller Features:
• Power-on Reset (POR), Power-up Timer (PWRT),
and Oscillator Start-up Timer (OST)
• Watchdog Timer (WDT) with its own on-chip RC
oscillator
• On-chip Boot RAM for boot loader application
• 8-bit or 16-bit external memory interface modes
• Up to two software programmable chip select signals (CS1 and CS2)
• One programmable chip I/O select signal (CSIO)
for memory mapped I/O expansion
• Power saving SLEEP mode
• Different oscillator options, including:
- 4X Phase Lock Loop (of primary oscillator)
- Secondary Oscillator (32 kHz) clock input
CMOS Technology:
•
•
•
•
•
Low power, high speed CMOS technology
Fully static design
Wide operating voltage range (2.0V to 5.5V)
Industrial and Extended temperature ranges
Low power consumption
Advance Information
DS39541A-page 1
PIC18C601/801
Pin Diagrams
RD4/AD4
RD5/AD5
RD6/AD6
RD7/AD7
VSS
RD1/AD1
RD2/AD2
RD3/AD3
RE5/AD13
RE6/AD14
RE7/AD15
RD0/AD0
VDD
RE2/AD10
RE3/AD11
RE4/AD12
64-Pin TQFP
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
RE1/AD9
1
48
RB0/INT0
RE0/AD8
2
47
RB1/INT1
RG0/ALE
3
46
RB2/INT2
RG1/OE
4
45
RB3/CCP2
RG2/WRL
5
44
RB4
RG3/WRH
6
43
RB5
MCLR/VPP
RG4/BA0
7
42
RB6
41
VSS
VSS
9
40
OSC2/CLKO
VDD
10
39
OSC1/CLKI
RF7/UB
11
38
VDD
RF6/LB
12
37
RB7
RF5/CS1
13
36
RC5/SDO
RF4/A16
14
35
RC4/SDI/SDA
RF3/CSIO
15
34
RC3/SCK/SCL
RF2/AN7
16
33
RC2/CCP1
PIC18C601
8
DS39541A-page 2
Advance Information
RC0/T1OSO/T13CKI
RC6/TX/CK
RC7/RX/DT
RA4/T0CKI
RC1/T1OSI
VDD
RA5/SS/AN4/LVDIN
RA0/AN0
VSS
RA1/AN1
RA2/AN2/VREF-
AVSS
RA3/AN3/VREF+
RF0/AN5
AVDD
RF1/AN6
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
 2001 Microchip Technology Inc.
PIC18C601/801
Pin Diagrams (Cont.’d)
RE2/AD10
RE3/AD11
RE4/AD12
RE5/AD13
RE6/AD14
RE7/AD15
RD0/AD0
VDD
NC
VSS
RD1/AD1
RD2/AD2
RD3/AD3
RD4/AD4
RD5/AD5
RD6/AD6
RD7/AD7
68-Pin PLCC
9 8 7 6 5 4 3 2 1 68 67 66 65 64 63 62 61
RE1/AD9
RE0/AD8
RG0/ALE
RG1/OE
RG2/WRL
RG3/WRH
MCLR/VPP
RG4/BA0
NC
VSS
VDD
RF7/UB
RF6/LB
RF5/CS1
RF4/A16
RF3/CSIO
RF2/AN7
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
PIC18C601
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
RB0/INT0
RB1/INT1
RB2/INT2
RB3/CCP2
RB4
RB5
RB6
VSS
NC
OSC2/CLKO
OSC1/CLKI
VDD
RB7
RC5/SDO
RC4/SDI/SDA
RC3/SCK/SCL
RC2/CCP1
 2001 Microchip Technology Inc.
VDD
RA5/SS/AN4/LVDIN
RA4/T0CKI
RC1/T1OSI
RC0/T1OSO/T13CKI
RC6/TX/CK
RC7/RX/DT
RF1/AN6
RF0/AN5
AVDD
AVSS
RA3/AN3/VREF+
RA2/AN2/VREFRA1/AN1
RA0/AN0
NC
VSS
27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
Advance Information
DS39541A-page 3
PIC18C601/801
Pin Diagrams (Cont.’d)
RD4/AD4
RD5/AD5
RD6/AD6
RD7/AD7
RJ0/D7
RJ1/D6
VSS
RD1/AD1
RD2/AD2
RD3/AD3
RE5/AD13
RE6/AD14
RE7/AD15
RD0/AD0
VDD
RH1/A17
RH0/A16
RE2/AD10
RE3/AD11
RE4/AD12
80-Pin TQFP
80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61
RH2/A18
1
60
RJ5/D5
RH3/A19
2
59
RE1/AD9
3
58
RJ4/D4
RB0/INT0
RE0/AD8
4
57
RB1/INT1
RG0/ALE
5
56
RB2/INT2
RG1/OE
6
55
RB3/CCP2
RG2/WRL
7
54
RB4
RG3/WRH
8
53
RB5
MCLR/VPP
RG4/BA0
9
52
RB6
10
51
VSS
VSS
11
50
OSC2/CLKO
VDD
12
49
OSC1/CLKI
RF7/UB
13
48
VDD
RF6/LB
14
47
RB7
RF5/CS1
15
46
RC5/SDO
RF4/CS2
16
45
RC4/SDI/SDA
RF3/CSIO
17
44
RC3/SCK/SCL
RF2/AN7
18
43
RC2/CCP1
RH4/AN8
19
42
RJ3/D3
RH5/AN9
20
41
RJ2/D2
PIC18C801
DS39541A-page 4
Advance Information
RJ0/D0
RJ1/D1
RC0/T1OSO/T13CKI
RC6/TX/CK
RC7/RX/DT
RA4/T0CKI
RC1/T1OSI
RA5/SS/AN4/LVDIN
VDD
RA1/AN1
RA0/AN0
VSS
AVSS
RA3/AN3/VREF+
RA2/AN2/VREF-
RF0/AN5
AVDD
RF1/AN6
RH6/AN10
RH7/AN11
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
 2001 Microchip Technology Inc.
PIC18C601/801
Pin Diagrams (Cont.’d)
RH1/A17
RH0/A16
RE2/AD10
RE3/AD11
RE4/AD12
RE5/AD13
RE6/AD14
RE7/AD15
RD0/AD0
VDD
NC
VSS
RD1/AD1
RD2/AD2
RD3/AD3
RD4/AD4
RD5/AD5
RD6/AD6
RD7/AD7
RJ7/D7
RJ6/D6
84-Pin PLCC
11 10 9 8 7 6 5 4 3 2 1 84 83 82 81 80 79 78 77 76 75
RH2/A18
RH3/A19
RE1/AD9
RE0/AD8
RG0/ALE
RG1/OE
RG2/WRL
RG3/WRH
MCLR/VPP
RG4/BA0
NC
VSS
VDD
RF7/UB
RF6/LB
RF5/CS1
RF4/CS2
RF3/CSIO
RF2/AN7
RH4/AN8
RH5/AN9
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
PIC18C801
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
RJ5/D5
RJ4/D4
RB0/INT0
RB1/INT1
RB2/INT2
RB3/CCP2
RB4
RB5
RB6
VSS
NC
OSC2/CLKO
OSC1/CLKI
VDD
RB7
RC5/SDO
RC4/SDI/SDA
RC3/SCK/SCL
RC2/CCP1
RJ3/D3
RJ2/D2
RH6/AN10
RH7/AN11
RF1/AN6
RF0/AN5
AVDD
AVSS
RA3/AN3/VREF+
RA2/AN2/VREFRA1/AN1
RA0/AN0
NC
VSS
VDD
RA5/SS/AN4/LVDIN
RA4/T0CKI
RC1/T1OSI
RC0/T1OSO/T13CKI
RC6/TX/CK
RC7/RX/DT
RJ0/D0
RJ1/D1
33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 5
PIC18C601/801
Table of Contents
1.0
Device Overview.................................................................................................................................................. 9
2.0
Oscillator Configurations.................................................................................................................................... 21
3.0
RESET............................................................................................................................................................... 29
4.0
Memory Organization ........................................................................................................................................ 39
5.0
External Memory Interface................................................................................................................................. 63
6.0
Table Reads/Table Writes ................................................................................................................................. 73
7.0
8 X 8 Hardware Multiplier .................................................................................................................................. 85
8.0
Interrupts............................................................................................................................................................ 89
9.0
I/O Ports........................................................................................................................................................... 103
10.0 Timer0 Module................................................................................................................................................. 127
11.0 Timer1 Module................................................................................................................................................. 130
12.0 Timer2 Module................................................................................................................................................. 135
13.0 Timer3 Module................................................................................................................................................. 137
14.0 Capture/Compare/PWM (CCP) Modules......................................................................................................... 141
15.0 Master Synchronous Serial Port (MSSP) Module............................................................................................ 149
16.0 Addressable Universal Synchronous Asynchronous Receiver Transmitter (USART) ..................................... 177
17.0 10-bit Analog-to-Digital Converter (A/D) Module ............................................................................................. 193
18.0 Low Voltage Detect.......................................................................................................................................... 203
19.0 Special Features of the CPU ........................................................................................................................... 207
20.0 Instruction Set Summary ................................................................................................................................. 215
21.0 Development Support ...................................................................................................................................... 259
22.0 Electrical Characteristics ................................................................................................................................. 265
23.0 DC and AC Characteristics Graphs and Tables .............................................................................................. 295
24.0 Packaging Information ..................................................................................................................................... 297
Appendix A: Data Sheet Revision History.................................................................................................................. 303
Appendix B: Device Differences ................................................................................................................................ 303
Appendix C: Device Migrations .................................................................................................................................. 304
Appendix D: Migrating from other PICmicro Devices ................................................................................................. 304
Appendix E: Development Tool Version Requirements ............................................................................................. 305
Index ........................................................................................................................................................................... 307
On-Line Support .......................................................................................................................................................... 315
Reader Response ....................................................................................................................................................... 316
Product Identification System...................................................................................................................................... 317
DS39541A-page 6
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TO OUR VALUED CUSTOMERS
It is our intention to provide our valued customers with the best documentation possible to ensure successful use of your Microchip
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enhanced as new volumes and updates are introduced.
If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via
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We welcome your feedback.
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http://www.microchip.com
You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page.
The last character of the literature number is the version number, (e.g., DS30000A is version A of document DS30000).
Errata
An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current
devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision
of silicon and revision of document to which it applies.
To determine if an errata sheet exists for a particular device, please check with one of the following:
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• Your local Microchip sales office (see last page)
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When contacting a sales office or the literature center, please specify which device, revision of silicon and data sheet (include literature number) you are using.
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Register on our web site at www.microchip.com/cn to receive the most current information on all of our products.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 7
PIC18C601/801
NOTES:
DS39541A-page 8
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
1.0
DEVICE OVERVIEW
An overview of features is shown in Table 1-1.
This document contains device specific information for
the following two devices:
1.
2.
PIC18C601
PIC18C801
Device block diagrams are provided in Figure 1-1 for
the 64/68-pin configuration, and Figure 1-2 for the 80/
84-pin configuration. The pinouts for both packages
are listed in Table 1-2.
The PIC18C601 is available in 64-pin TQFP and 68-pin
PLCC packages. The PIC18C801 is available in 80-pin
TQFP and 84-pin PLCC packages.
TABLE 1-1:
DEVICE FEATURES
Features
Operating Frequency
External
Program Memory
PIC18C601
PIC18C801
DC - 25 MHz
DC - 25 MHz
Bytes
256K
2M
Max. # of Single Word
Instructions
128K
1M
1536
1536
15
15
Ports A - G
Ports A - H, J
4
4
Data Memory (Bytes)
Interrupt Sources
I/O Ports
Timers
Capture/Compare/PWM modules
2
2
MSSP,
Addressable USART
MSSP,
Addressable USART
8 input channels
12 input channels
POR,
RESET Instruction, Stack Full,
Stack Underflow (PWRT, OST)
POR,
RESET Instruction, Stack Full,
Stack Underflow (PWRT, OST)
Programmable Low Voltage Detect
Yes
Yes
8-bit External Memory Interface
Yes
Yes
8-bit De-multiplexed External
Memory Interface
No
Yes
16-bit External Memory Interfaces
Yes
Yes
On-chip Chip Select Signals
CS1
CS1, CS2
Serial Communications
10-bit Analog-to-Digital Module
RESETS (and Delays)
On-chip I/O Chip Select Signal
Instruction Set
Packages
 2001 Microchip Technology Inc.
Yes
Yes
75 Instructions
75 Instructions
64-pin TQFP
68-pin PLCC
80-pin TQFP
84-pin PLCC
Advance Information
DS39541A-page 9
PIC18C601/801
FIGURE 1-1:
PIC18C601 BLOCK DIAGRAM
Data Bus<8>
AD7:AD0
Table Pointer<21>
21
21
RA0/AN0
RA1/AN1
RA2/AN2/VREFRA3/AN3/VREF+
RA4/T0CKI
RA5/AN4/SS/LVDIN
Data Latch
5
8
8
Data RAM
1 Kbyte
inc/dec logic
Address Latch
20
PCLATU PCLATH
System Bus Interface
PCU PCH PCL
Program Counter
12
4
BSR
Program Memory
(up to 256 Kbytes)
PORTB
RB0/INT0
RB1/INT1
RB2/INT2
RB3/CCP2
RB4
RB5
RB6
RB7
12
Address<12>
21
Address Latch
PORTA
31 Level Stack
Data Latch
4
Bank0, F
FSR0
FSR1
FSR2
12
PORTC
16
Decode
Table Latch
inc/dec
logic
RC0/T1OSO/T13CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX1/CK1
RC7/RX1/DT1
8
ROM Latch
IR
A16, AD15:AD8
OSC2/CLKO
OSC1/CLKI
RD7:RD0/AD7:AD0
PRODH PRODL
3
Timing
Generation
T1OSI
T1OSO
PORTD
8
Instruction
Decode &
Control
Power-up
Timer
Oscillator
Start-upTimer
Power-on
Reset
Watchdog
Timer
Low Voltage
Detect
MCLR
8 x 8 Multiply
8
PORTE
BITOP
8
WREG
8
8
RE7:RE0/AD15:AD8
8
ALU<8>
PORTF
8
RF0/AN5
RF1/AN6
RF2/AN7
RF3/CSIO
RF4/A16
RF5/CS1
RF6/LB
RF7/UB
VDD, VSS
PORTG
Timer0
Timer1
Timer2
CCP1
CCP2
Synchronous
Serial Port
Timer3
RG0/ALE
RG1/OE
RG2/WRL
RG3/WRH
RG4/BA0
USART1
10-bit A/D
DS39541A-page 10
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 1-2:
PIC18C801 BLOCK DIAGRAM
Data Bus<8>
AD7:AD0
TablePointer<21>
21
RA0/AN0
RA1/AN1
RA2/AN2/VREFRA3/AN3/VREF+
RA4/T0CKI
RA5/AN4/SS/LVDIN
Data Latch
5
21
8
8
Data RAM
1 Kbyte
inc/dec logic
PORTB
Address Latch
20
PCLATU PCLATH
System Bus Interface
PCU PCH PCL
Program Counter
Program Memory
(up to 2 Mbytes)
RB0/INT0
RB1/INT1
RB2/INT2
RB3/CCP2
RB4
RB5
RB6
RB7
12
Address<12>
21
Address Latch
PORTA
12
4
BSR
31 Level Stack
Data Latch
16
Decode
Table Latch
4
Bank0,F
FSR0
FSR1
FSR2
12
PORTC
RC0/T1OSO/T13CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX1/CK1
RC7/RX1/DT1
inc/dec
logic
8
ROM Latch
IR
PORTD
A19:A16, AD15:AD0
8
Instruction
Decode &
Control
OSC2/CLKO
OSC1/CLKI
T1OSI
T1OSO
RD7:RD0/AD7:AD0
PRODH PRODL
3
Timing
Generation
Power-up
Timer
Oscillator
Start-upTimer
Power-on
Reset
Watchdog
Timer
Low Voltage
Detect
MCLR
PORTE
8 x 8 Multiply
8
BITOP
8
WREG
8
RE7:RE0/AD15:AD8
8
PORTF
8
RF0/AN5
RF1/AN6
RF2/AN7
RF3/CSIO
RF4/CS2
RF5/CS1
RF6/LB
RF7/UB
ALU<8>
8
VDD, VSS
PORTG
RG0/ALE
RG1/OE
RG2/WRL
RG3/WRH
RG4/BA0
Timer0
Timer1
Timer2
Timer3
PORTH
RH3:RH0/A19:A16
RH4/AN8
RH5/AN9
RH6/AN10
RH7/AN11
CCP1
CCP2
Synchronous
Serial Port
USART1
PORTJ
RJ7:RJ0/D7:D0
10-bit A/D
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 11
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS
Pin Number
Pin Name
PIC18C601
MCLR/VPP
MCLR
PIC18C801
TQFP
PLCC
TQFP
PLCC
7
16
9
20
Buffer
Type
Description
I
ST
Master clear (RESET) input. This pin is
an active low RESET to the device.
Programming voltage input.
These pins should be left
unconnected.
P
VPP
NC
—
OSC1/CLKI
OSC1
39
1, 18,
35, 52
50
—
49
1, 22,
43, 64
62
CLKI
OSC2/CLKO
OSC2
40
51
50
TTL
ST
I
P
=
=
=
=
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
DS39541A-page 12
—
—
I
CMOS/ST
I
CMOS
O
—
O
—
Oscillator crystal input or external clock
source input. ST buffer when in RC
mode. Otherwise CMOS.
External clock source input.
Always associated with pin function
OSC1 (see OSC1/CLKI, OSC2/CLKO
pins).
63
CLKO
Legend:
Pin
Type
CMOS
Analog
O
OD
=
=
=
=
Oscillator crystal output.
Connects to crystal or resonator in
Crystal Oscillator mode.
In RC mode, OSC2 pin outputs CLKO,
which has 1/4 the
frequency of OSC1 and denotes the
instruction cycle rate.
CMOS compatible input or output
Analog input
Output
Open Drain (no P diode to VDD)
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
PIC18C801
TQFP
PLCC
TQFP
PLCC
RA0/AN0
RA0
AN0
24
34
30
42
RA1/AN1
RA1
AN1
RA2/AN2/VREFRA2
AN2
VREFRA3/AN3/VREF+
RA3
AN3
VREF+
RA4/T0CKI
RA4
23
Pin
Type
Buffer
Type
Description
PORTA is a bi-directional I/O port.
22
21
28
33
32
31
39
29
28
27
34
TTL
Analog
Digital I/O.
Analog input 0.
I/O
I
TTL
Analog
Digital I/O.
Analog input 1.
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog input 2.
A/D reference voltage (Low) input.
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog input 3.
A/D reference voltage (High) input.
I/O
ST/OD
I
ST
Digital I/O – Open drain when
configured as output.
Timer0 external clock input.
41
40
39
47
T0CKI
RA5/AN4/SS/LVDIN
27
38
33
46
RA5
AN4
SS
LVDIN
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
I
= Input
P = Power
 2001 Microchip Technology Inc.
I/O
I
I/O
I
I
I
TTL
Digital I/O.
Analog
Analog input 4.
ST
SPI slave select input.
Analog
Low voltage detect input.
CMOS = CMOS compatible input or output
Analog = Analog input
O
= Output
OD
= Open Drain (no P diode to VDD)
Advance Information
DS39541A-page 13
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
TQFP
PLCC
PIC18C801
TQFP
Pin
Type
Buffer
Type
PLCC
Description
PORTB is a bi-directional I/O port. PORTB
can be software programmed for internal
weak pull-ups on all inputs.
RB0/INT0
RB0
INT0
48
RB1/INT1
RB1
INT1
RB2/INT2
RB2
INT2
RB3/CCP2
RB3
CCP2
47
46
45
60
59
58
57
58
57
56
55
72
54
53
52
68
67
66
RB7
37
48
47
60
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
DS39541A-page 14
I/O
I
TTL
ST
Digital I/O.
External interrupt 1.
I/O
I
TTL
ST
Digital I/O.
External interrupt 2.
I/O
I/O
TTL
ST
69
56
55
54
=
=
=
=
Digital I/O.
External interrupt 0.
70
44
43
42
TTL
ST
I
P
TTL
ST
71
RB4
RB5
RB6
Legend:
I/O
I
Digital I/O.
Capture2 input, Compare2 output,
PWM2 output.
I/O
TTL
Digital I/O, Interrupt-on-change pin.
I/O
TTL
Digital I/O, Interrupt-on-change pin.
I/O
TTL
Digital I/O, Interrupt-on-change pin.
I
ST
ICSP programming clock.
I/O
TTL
Digital I/O, Interrupt-on-change pin.
I/O
ST
ICSP programming data.
CMOS = CMOS compatible input or output
Analog = Analog input
O
= Output
OD
= Open Drain (no P diode to VDD)
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
PIC18C801
TQFP
PLCC
TQFP
PLCC
30
41
36
49
Pin
Type
Buffer
Type
Description
PORTC is a bi-directional I/O port.
RC0/T1OSO/T13CKI
RC0
T1OSO
T13CKI
RC1/T1OSI
RC1
T1OSI
RC2/CCP1
RC2
CCP1
RC3/SCK/SCL
RC3
SCK
29
33
34
40
44
45
35
43
44
35
RC5/SDO
RC5
SDO
RC6/TX/CK
RC6
TX
CK
RC7/RX/DT
RC7
RX
DT
Legend: TTL
ST
I
P
36
31
32
46
47
42
43
45
46
37
38
ST
I/O
I
ST
CMOS
I/O
I/O
ST
ST
Digital I/O.
Capture1 input/Compare1
output/PWM1 output.
I/O
I/O
ST
ST
I/O
ST
Digital I/O.
Synchronous serial clock
input/output for SPI mode.
Synchronous serial clock
input/output for I2C mode.
I/O
I
I/O
ST
ST
ST
Digital I/O.
SPI data in.
I/O
O
ST
—
Digital I/O.
SPI data out.
I/O
O
I/O
ST
—
ST
Digital I/O.
USART asynchronous transmit.
USART synchronous clock.
Digital I/O.
Timer1 oscillator input.
57
58
I2C data I/O.
59
50
51
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
 2001 Microchip Technology Inc.
ST
Digital I/O.
Timer1 oscillator output.
Timer1/Timer3 external clock input.
56
I/O
I
I/O
=
=
=
=
—
48
SCL
RC4/SDI/SDA
RC4
SDI
SDA
I/O
O
I
ST
Digital I/O.
ST
USART asynchronous receive.
ST
USART synchronous data.
CMOS = CMOS compatible input or output
Analog = Analog input
O
= Output
OD
= Open Drain (no P diode to VDD)
Advance Information
DS39541A-page 15
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
TQFP
PLCC
PIC18C801
TQFP
Pin
Type
Buffer
Type
PLCC
Description
PORTD is a bi-directional I/O port. These
pins have TTL input buffers when external
memory is enabled.
RD0/AD0
RD0
AD0
58
RD1/AD1
RD1
AD1
RD2/AD2
RD2
AD2
RD3/AD3
RD3
AD3
RD4/AD4
RD4
AD4
RD5/AD5
RD5
AD5
RD6/AD6
RD6
AD6
RD7/AD7
RD7
AD7
Legend: TTL
ST
I
P
55
54
53
52
51
50
49
3
67
66
65
64
63
62
61
72
69
68
67
66
65
64
63
3
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 0.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 1.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 2.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 3.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 4.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 5.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 6.
83
82
81
80
79
78
77
I/O
I/O
=
=
=
=
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
DS39541A-page 16
ST
Digital I/O.
TTL
External memory address/data 7.
CMOS = CMOS compatible input or output
Analog = Analog input
O
= Output
OD
= Open Drain (no P diode to VDD)
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
PIC18C801
TQFP
PLCC
TQFP
PLCC
RE0/AD8
RE0
AD8
2
11
4
15
RE1/AD9
RE1
AD9
RE2/AD10
RE2
AD10
RE3/AD11
RE3
AD11
RE4/AD12
RE4
AD12
RE5/AD13
RE5
AD13
RE6/AD14
RE6
AD14
RE7/AD15
RE7
AD15
Legend: TTL
ST
I
P
1
Pin
Type
Buffer
Type
Description
PORTE is a bi-directional I/O port.
64
63
62
61
60
59
10
9
8
7
6
5
4
3
78
77
76
75
74
73
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 8.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 9.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 10.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 11.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 12.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 13.
I/O
I/O
ST
TTL
Digital I/O.
External memory address/data 14.
14
9
8
7
6
5
4
I/O
I/O
=
=
=
=
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
 2001 Microchip Technology Inc.
ST
Digital I/O.
ST
External memory address/data 15.
CMOS = CMOS compatible input or output
Analog = Analog input
O
= Output
OD
= Open Drain (no P diode to VDD)
Advance Information
DS39541A-page 17
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
PIC18C801
TQFP
PLCC
TQFP
PLCC
RF0/AN5
RF0
AN5
18
28
24
36
RF1/AN6
RF1
AN6
RF2/AN7
RF2
AN7
RF3/CSIO
RF3
CSIO
RF4/A16
RF4/CS2
RF4
A16
CS2
RF5/CS1
RF5
CS1
RF6/LB
RF6
LB
17
Pin
Type
Buffer
Type
Description
PORTF is a bi-directional I/O port.
16
15
Legend:
17
—
—
16
28
22
21
15
14
13
ST
Analog
Digital I/O.
Analog input 6.
I/O
I
ST
Analog
Digital I/O.
Analog input 7.
I/O
I/O
ST
ST
Digital I/O.
System bus chip select I/O.
I/O
I/O
O
ST
TTL
TTL
Digital I/O.
External memory address 16.
Chip select 2.
I/O
O
ST
TTL
Digital I/O.
Chip select 1.
I/O
O
ST
TTL
Digital I/O.
Low byte select signal for external
memory interface.
I/O
O
ST
TTL
27
26
25
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
DS39541A-page 18
I/O
I
29
—
23
Digital I/O.
Analog input 5.
30
24
11
=
=
=
=
25
18
ST
Analog
35
—
12
TTL
ST
I
P
26
23
14
13
RF7/UB
RF7
UB
27
I/O
I
CMOS
Analog
O
OD
=
=
=
=
Digital I/O.
High byte select signal for external
memory interface.
CMOS compatible input or output
Analog input
Output
Open Drain (no P diode to VDD)
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
PIC18C801
TQFP
PLCC
TQFP
PLCC
RG0/ALE
RG0
ALE
3
12
5
16
RG1/OE
RG1
OE
RG2/WRL
RG2
WRL
RG3/WRH
RG3
WRH
RG4/BA0
RG4
BA0
4
RH0/A16
RH0
A16
RH1/A17
RH1
A17
RH2/A18
RH2
A18
RH3/A19
RH3
A19
RH4/AN8
RH4
AN8
RH5/AN9
RH5
AN9
—
RH6/AN10
RH6
AN10
RH7/AN11
RH7
AN11
Legend: TTL
ST
I
P
—
Pin
Type
Buffer
Type
Description
PORTG is a bi-directional I/O port.
5
6
8
—
—
—
—
—
—
13
14
15
17
—
—
—
—
—
—
—
—
6
7
8
10
79
80
1
2
19
20
21
22
I/O
O
ST
TTL
Digital I/O.
Address Latch Enable.
I/O
O
ST
TTL
Digital I/O.
Output Enable.
I/O
O
ST
TTL
Digital I/O.
Write Low control.
I/O
O
ST
TTL
Digital I/O.
Write High control.
I/O
O
ST
TTL
I/O
O
ST
TTL
Digital I/O.
External memory address 16.
I/O
O
ST
Digital I/O.
External memory address 17.
I/O
O
ST
I/O
O
ST
I/O
I
ST
Analog
Digital I/O.
Analog input 8.
I/O
I
ST
Analog
Digital I/O.
Analog input 9.
I/O
I
ST
Analog
Digital I/O.
Analog input 10.
17
18
19
21
10
11
—
Digital I/O.
External memory address 18.
13
—
Digital I/O.
External memory address 19.
31
32
33
34
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
 2001 Microchip Technology Inc.
—
12
I/O
I
=
=
=
=
Digital I/O.
System bus byte address 0.
PORTH is a bi-directional I/O port.
ST
Digital I/O.
Analog
Analog input 11.
CMOS = CMOS compatible input or output
Analog = Analog input
O
= Output
OD
= Open Drain (no P diode to VDD)
Advance Information
DS39541A-page 19
PIC18C601/801
TABLE 1-2:
PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
Pin Name
PIC18C601
PIC18C801
TQFP
PLCC
TQFP
PLCC
RJ0/D0
RJ0
D0
—
—
39
52
RJ1/D1
RJ1
D1
RJ2/D2
RJ2
D2
RJ3/D3
RJ3
D3
RJ4/D4
RJ4
D4
RJ5/D5
RJ5
D5
—
RJ6/D6
RJ6
D6
RJ7/D7
RJ7
D7
VSS
—
Pin
Type
Buffer
Type
Description
PORTJ is a bi-directional I/O port.
—
—
—
—
—
9, 25,
41, 56
10,26,
38, 57
20
19
VDD
AVSS
AVDD
Legend:
TTL
ST
I
P
=
=
=
=
—
—
—
—
—
—
—
19, 36,
53, 68
2, 20,
37, 49
30
29
40
41
42
59
60
61
62
11,31,
51, 70
12,32,
48, 71
26
25
ST
TTL
Digital I/O.
System bus data bit 0.
I/O
I/O
ST
TTL
Digital I/O.
System bus data bit 1.
I/O
I/O
ST
TTL
Digital I/O.
System bus data bit 2.
I/O
I/O
ST
TTL
Digital I/O.
System bus data bit 3.
I/O
I/O
ST
TTL
Digital I/O.
System bus data bit 4.
I/O
I/O
ST
TTL
Digital I/O.
System bus data bit 5.
I/O
I/O
ST
TTL
Digital I/O.
System bus data bit 6.
I/O
I/O
P
ST
TTL
—
Digital I/O.
System bus data bit 7.
Ground reference for logic and I/O pins.
P
—
Positive supply for logic and I/O pins.
P
P
—
—
Ground reference for analog modules.
Positive supply for analog modules.
53
54
55
73
74
75
76
23, 44,
65, 84
2, 24,
45, 61
38
37
TTL compatible input
Schmitt Trigger input with CMOS levels
Input
Power
DS39541A-page 20
I/O
I/O
CMOS
Analog
O
OD
=
=
=
=
CMOS compatible input or output
Analog input
Output
Open Drain (no P diode to VDD)
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
2.0
OSCILLATOR
CONFIGURATIONS
2.1
Oscillator Types
FIGURE 2-1:
PIC18C601/801 can be operated in one of four oscillator modes, programmable by configuration bits
FOSC1:FOSC0 in CONFIG1H register:
1.
2.
3.
4.
LP
HS
RC
EC
2.2
C1(1)
CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS OR LP OSC
CONFIGURATION)
OSC1
XTAL
Low Power Crystal
High Speed Crystal/Resonator
External Resistor/Capacitor
External Clock
RS(2)
C2(1)
Crystal Oscillator/Ceramic
Resonators
OSC2
To
Internal
Logic
RF(3)
SLEEP
PIC18C601/801
Note 1: See Table 2-1 and Table 2-2 for recommended values of C1 and C2.
In LP or HS oscillator modes, a crystal or ceramic resonator is connected to the OSC1 and OSC2 pins to
establish oscillation. Figure 2-1 shows the pin connections. An external clock source may also be connected
to the OSC1 pin, as shown in Figure 2-3 and Figure 2-4.
2: A series resistor (RS) may be required for AT
strip cut crystals.
3: RF varies with the crystal chosen.
PIC18C601/801 oscillator design requires the use of a
parallel cut crystal.
Note:
Use of a series cut crystal may give a frequency out of the crystal manufacturer’s
specifications.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 21
PIC18C601/801
TABLE 2-1:
CERAMIC RESONATORS
Ranges Tested:
Mode
Freq.
OSC1
OSC2
HS
8.0 MHz
10 - 68 pF
10 - 68 pF
16.0 MHz
10 - 22 pF
10 - 22 pF
20.0 MHz
TBD
TBD
25.0 MHz
TBD
TBD
HS+PLL 4.0 MHz
TBD
TBD
These values are for design guidance only.
See notes on this page.
Resonators Used:
4.0 MHz Murata Erie CSA4.00MG
± 0.5%
8.0 MHz Murata Erie CSA8.00MT
± 0.5%
16.0 MHz Murata Erie CSA16.00MX
± 0.5%
All resonators used did not have built-in capacitors.
TABLE 2-2:
CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR
Osc Type
Crystal
Freq.
LP
32.0 kHz
33 pF
33 pF
200 kHz
15 pF
15 pF
4.0 MHz
15 pF
15 pF
8.0 MHz
15-33 pF
15-33 pF
20.0 MHz
15-33 pF
15-33 pF
25.0 MHz
TBD
TBD
4.0 MHz
15 pF
15 pF
HS
HS+PLL
Cap. Range
C1
Cap. Range
C2
Note 1: Recommended values of C1 and C2 are
identical to the ranges tested (Table 2-1).
2: Higher capacitance increases the stability
of the oscillator, but also increases the
start-up time.
3: Since each resonator/crystal has its own
characteristics, the user should consult the
resonator/crystal manufacturer for appropriate values of external components.
4: Rs may be required in HS mode to avoid
overdriving crystals with low drive level
specification.
2.3
For timing insensitive applications, the "RC" oscillator
mode offers additional cost savings. The RC oscillator
frequency is a function of the supply voltage, the resistor (REXT) and capacitor (CEXT) values and the operating temperature. In addition to this, the oscillator
frequency will vary from unit to unit due to normal process parameter variation. Furthermore, the difference
in lead frame capacitance between package types will
also affect the oscillation frequency, especially for low
CEXT values. The user also needs to take into account
variation due to tolerance of external R and C components used. Figure 2-2 shows how the RC combination
is connected.
In the RC oscillator mode, the oscillator frequency
divided by 4 is available on the OSC2 pin. This signal
may be used for test purposes or to synchronize other
logic.
FIGURE 2-2:
These values are for design guidance only.
See notes on this page.
Crystals Used
RC Oscillator
RC OSCILLATOR MODE
VDD
REXT
32.0 kHz
Epson C-001R32.768K-A
± 20 PPM
200 kHz
STD XTL 200.000kHz
± 20 PPM
1.0 MHz
ECS ECS-10-13-1
± 50 PPM
4.0 MHz
ECS ECS-40-20-1
± 50 PPM
8.0 MHz
EPSON CA-301 8.000M-C
± 30 PPM
20.0 MHz EPSON CA-301 20.000M-C
± 30 PPM
OSC1
CEXT
PIC18C601/801
VSS
FOSC/4
or I/O
Recommended values:
DS39541A-page 22
Internal
Clock
Advance Information
OSC2/CLKO
3 kΩ ≤ REXT ≤ 100 kΩ
CEXT > 20pF
 2001 Microchip Technology Inc.
PIC18C601/801
2.4
External Clock Input
2.5
The EC oscillator mode requires an external clock
source to be connected to the OSC1 pin. The feedback
device between OSC1 and OSC2 is turned off in these
modes to save current. There is no oscillator start-up
time required after a Power-on Reset or after a
recovery from SLEEP mode.
A Phase Lock Loop (PLL) circuit is provided as a software programmable option for users that want to multiply the frequency of the incoming crystal oscillator
signal by 4. For an input clock frequency of 6 MHz, the
internal clock frequency will be multiplied to 24 MHz.
This is useful for customers who are concerned with
EMI due to high frequency crystals.
In the EC oscillator mode, the oscillator frequency
divided by 4 is available on the OSC2 pin. This signal
may be used for test purposes or to synchronize other
logic. Figure 2-3 shows the pin connections for the EC
oscillator mode.
FIGURE 2-3:
The PLL is enabled by configuring HS oscillator mode
and setting the PLLEN bit in the OSCON register. If HS
oscillator mode is not selected, or PLLEN bit in
OSCCON register is clear, the PLL is not enabled and
the system clock will come directly from OSC1. HS
oscillator mode is the default for PIC18C601/801. In all
other modes, the PLLEN bit and the SCS1 bit are
forced to ‘0’.
EXTERNAL CLOCK INPUT
OPERATION (EC OSC
CONFIGURATION)
A PLL lock timer is used to ensure that the PLL has
locked before device execution starts. The PLL lock
timer has a time-out, referred to as TPLL.
OSC1
Clock from
ext. system
PIC18C601/801
FOSC/4
FIGURE 2-4:
HS4 (PLL)
OSC2
PLL BLOCK DIAGRAM
HS Osc
PLL Enable
OSCOUT
Phase
Comparator
OSCIN
FIN
Loop
Filter
FOUT
Feedback Divider
3
 2001 Microchip Technology Inc.
VCO
2
Advance Information
1
0
MUX
Crystal
Osc
CVCO
SYSCLK
DS39541A-page 23
PIC18C601/801
2.6
2.6.1
Oscillator Switching Feature
PIC18C601/801 devices include a feature that allows
the system clock source to be switched from the main
oscillator to an alternate low frequency clock source.
For PIC18C601/801 devices, this alternate clock
source is the Timer1 oscillator. If a low frequency crystal (32 kHz, for example) has been attached to the
Timer1 oscillator pins and the Timer1 oscillator has
been enabled, the device can switch to a low power
execution mode. Figure 2-5 shows a block diagram of
the system clock sources.
FIGURE 2-5:
SYSTEM CLOCK SWITCH BIT
The system clock source switching is performed under
software control. The system clock switch bit, SCS0
(OSCCON register), controls the clock switching. When
the SCS0 bit is ’0’, the system clock source comes from
the main oscillator, selected by the FOSC2:FOSC0 configuration bits in CONFIG1H register. When the SCS0 bit
is set, the system clock source will come from the Timer1
oscillator. The SCS0 bit is cleared on all forms of RESET.
Note:
The Timer1 oscillator must be enabled to
switch the system clock source. The
Timer1 oscillator is enabled by setting the
T1OSCEN bit in the Timer1 control register
(T1CON). If the Timer1 oscillator is not
enabled, any write to the SCS0 bit will be
ignored (SCS0 bit forced cleared) and the
main oscillator will continue to be the system clock source.
DEVICE CLOCK SOURCES
PIC18C601/801
Main Oscillator
OSC2
SLEEP
TOSC/4
Timer 1 Oscillator
T1OSO
TSCLK
MUX
TOSC
OSC1
T1OSI
4 x PLL
TT1P
Clock
Source
T1OSCEN
Enable
Oscillator
Clock Source option
for other modules
Note: I/O pins have diode protection to VDD and VSS.
DS39541A-page 24
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 2-1:
OSCCON REGISTER
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
—
—
LOCK
PLLEN
SCS1
SCS0
bit 7
bit 0
bit 7-4
Unimplemented: Read as '0'
bit 3
LOCK: Phase Lock Loop Lock Status bit
1 = Phase Lock Loop output is stable as system clock
0 = Phase Lock Loop output is not stable and cannot be used as system clock
bit 2
PLLEN: Phase Lock Loop Enable bit
1 = Enable Phase Lock Loop output as system clock
0 = Disable Phase Lock Loop
bit 1
SCS1: System Clock Switch bit 1
When PLLEN and LOCK bit are set:
1 = Use PLL output
0 = Use primary oscillator/clock input pin
When PLLEN bit or LOCK bit is cleared:
Bit is forced clear
bit 0
SCS0: System Clock Switch bit 0
When T1OSCEN bit is set:
1 = Switch to Timer1 oscillator/clock pin
0 = Use primary oscillator/clock input pin
When T1OSCEN is cleared:
Bit is forced clear
Legend:
2.6.2
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
OSCILLATOR TRANSITIONS
PIC18C601/801 devices contain circuitry to prevent
"glitches" when switching between oscillator sources.
Essentially, the circuitry waits for eight rising edges of
the clock source that the processor is switching to.
This ensures that the new clock source is stable and
that its pulse width will not be less than the shortest
pulse width of the two clock sources.
A timing diagram indicating the transition from the main
oscillator to the Timer1 oscillator is shown in Figure 2-6.
The Timer1 oscillator is assumed to be running all the
time. After the SCS0 bit is set, the processor is frozen
at the next occurring Q1 cycle. After eight synchronization cycles are counted from the Timer1 oscillator, operation resumes. No additional delays are required after
the synchronization cycles.
 2001 Microchip Technology Inc.
x = Bit is unknown
The sequence of events that takes place when switching from the Timer1 oscillator to the main oscillator will
depend on the mode of the main oscillator. In addition
to eight clock cycles of the main oscillator, additional
delays may take place.
If the main oscillator is configured for an external crystal (HS, LP), the transition will take place after an oscillator start-up time (TOST) has occurred. A timing
diagram indicating the transition from the Timer1 oscillator to the main oscillator for HS and LP modes is
shown in Figure 2-7.
Advance Information
DS39541A-page 25
PIC18C601/801
FIGURE 2-6:
TIMING DIAGRAM FOR TRANSITION FROM OSC1 TO TIMER1 OSCILLATOR
Q1 Q2
Q3 Q4
Q1
Q1
Q2
Q4
Q3
Q1
Q2
Q3
Q4
Q1
TT1P
1
T1OSI
2
3
4
5
6
7
8
TSCS
OSC1
TOSC
Internal
System
Clock
SCS0
(OSCCON<0>)
Program
Counter
Note:
TDLY
PC
PC + 4
PC + 2
Delay on internal system clock is eight oscillator cycles for synchronization.
FIGURE 2-7:
TIMING DIAGRAM FOR TRANSITION BETWEEN TIMER1 AND OSC1 (HS, LP)
Q3
Q4
Q1
Q1
TT1P
Q2 Q3
Q4
Q1
Q2
Q3
T1OSI
1
OSC1
2
3
TOST
4
5
6
7
8
TSCS
OSC2
Internal System
Clock
TOSC
SCS0
(OSCCON<0>)
Program Counter
Note:
PC
PC + 2
PC + 4
TOST = 1024TOSC (drawing not to scale).
DS39541A-page 26
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
put is not used, so the system oscillator will come from
OSC1 directly and additional delay of TPLL is not
required. A timing diagram indicating the transition from
the Timer1 oscillator to the main oscillator for HS4
mode is shown in Figure 2-9.
If the main oscillator is configured for HS4 (PLL) mode
with SCS1 bit set to ‘1’, an oscillator start-up time
(TOST), plus an additional PLL time-out (TPLL) will
occur. The PLL time-out is typically 2 ms and allows the
PLL to lock to the main oscillator frequency. A timing
diagram indicating the transition from the Timer1 oscillator to the main oscillator for HS4 mode is shown in
Figure 2-8.
If the main oscillator is configured in the RC or EC
modes, there is no oscillator start-up time-out. Operation will resume after eight cycles of the main oscillator
have been counted. A timing diagram indicating the
transition from the Timer1 oscillator to the main oscillator for RC and EC modes is shown in Figure 2-10.
If the main oscillator is configured for HS4 (PLL) mode,
with SCS1 bit set to ‘0’, only oscillator start-up time
(TOST) will occur. Since SCS1 bit is set to ‘0’, PLL out-
FIGURE 2-8:
TIMING FOR TRANSITION BETWEEN TIMER1 AND OSC1 (HS4 WITH SCS1 = 1)
Q4
TT1P
Q1
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4
T1OSI
OSC1
TOST
TPLL
OSC2
TSCS
TOSC
PLL Clock
Input
1
2
3
4
5
6
7
8
Internal System
Clock
SCS0
(OSCCON<0>)
Program Counter
PC
PC + 2
PC + 4
Note: TOST = 1024TOSC (drawing not to scale).
FIGURE 2-9:
TIMING FOR TRANSITION BETWEEN TIMER1 AND OSC1 (HS4 WITH SCS = 0)
Q4
TT1P
Q1
Q1
Q2
Q3
Q4
Q1
Q2
T1OSI
OSC1
TOSC
TOST
OSC2
TSCS
PLL
Clock
Output
TPLL
Internal
System
Clock
TDLY
SCS0
(OSCCON<0>)
Program
Counter
Note:
PC
PC + 2
PC + 4
TOST = 1024TOSC (drawing not to scale).
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 27
PIC18C601/801
FIGURE 2-10:
TIMING FOR TRANSITION BETWEEN TIMER1 AND OSC1 (RC, EC)
Q3
Q4
Q1
Q1 Q2
TT1P
T1OSI
TOSC
OSC1
1
2
3
4
5
6
7
Q3
Q4 Q1 Q2 Q3 Q4
8
OSC2
Internal System
Clock
SCS0
(OSCCON<0>)
TSCS
Program Counter
Note:
2.6.3
PC
RC oscillator mode assumed.
SCS0, SCS1 PRIORITY
If both SCS0 and SCS1 are set to ‘1’ simultaneously,
the SCS0 bit has priority over the SCS1 bit. This means
that the low power option will take precedence over the
PLL option. If both bits are cleared simultaneously, the
system clock will come from OSC1, after a TOST timeout. If only the SCS0 bit is cleared, the system clock will
come from the PLL output, following TOST and TPLL
time.
TABLE 2-3:
SCS0, SCS1 PRIORITY
SCS1
SCS0
0
0
1
1
0
1
0
1
2.7
PC + 4
PC + 2
Clock Source
Ext Oscillator OSC1
Timer1 Oscillator
HS + PLL
Timer1 Oscillator
Effects of SLEEP Mode on the
On-Chip Oscillator
When the device executes a SLEEP instruction, the
on-chip clocks and oscillator are turned off and the
device is held at the beginning of an instruction cycle
(Q1 state). With the oscillator off, the OSC1 and OSC2
signals will stop oscillating. Since all the transistor
switching currents have been removed, SLEEP mode
achieves the lowest current consumption of the device
(only leakage currents). Enabling any on-chip feature
that will operate during SLEEP, will increase the cur-
TABLE 2-4:
OSC Mode
rent consumed during SLEEP. The user can wake from
SLEEP through external RESET, Watchdog Timer
Reset, or through an interrupt.
2.8
Power-up Delays
Power-up delays are controlled by two timers, so that
no external RESET circuitry is required for most applications. The delays ensure that the device is kept in
RESET until the device power supply and clock are stable. For additional information on RESET operation,
see Section 3.0 RESET.
The first timer is the Power-up Timer (PWRT), which
optionally provides a fixed delay of TPWRT (parameter
#33) on power-up only. The second timer is the Oscillator Start-up Timer (OST), intended to keep the chip in
RESET until the crystal oscillator is stable.
PIC18C601/801 devices provide a configuration bit,
PWRTEN in CONFIG2L register, to enable or disable
the Power-up Timer. By default, the Power-up Timer is
enabled.
With the PLL enabled (HS4 oscillator mode), the time-out
sequence following a Power-on Reset is different from
other oscillator modes. The time-out sequence is as follows: the PWRT time-out is invoked after a POR time
delay has expired, then, the Oscillator Start-up Timer
(OST) is invoked. However, this is still not a sufficient
amount of time to allow the PLL to lock at high frequencies. The PWRT timer is used to provide an additional
time-out, called TPLL (parameter #7), to allow the PLL
ample time to lock to the incoming clock frequency.
OSC1 AND OSC2 PIN STATES IN SLEEP MODE
OSC1 Pin
OSC2 Pin
RC
Floating, external resistor should pull high
At logic low
EC
Floating
At logic low
LP and HS Feedback inverter disabled, at quiescent voltage level Feedback inverter disabled, at quiescent voltage level
Note: See Table 3-1 in Section 3.0 RESET, for time-outs due to SLEEP and MCLR Reset.
DS39541A-page 28
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
3.0
RESET
PIC18C601/801 devices differentiate between various
kinds of RESET:
a)
b)
c)
d)
e)
f)
g)
Power-on Reset (POR)
MCLR Reset during normal operation
MCLR Reset during SLEEP
Watchdog Timer (WDT) Reset during normal
operation
RESET Instruction
Stack Full Reset
Stack Underflow Reset
Most registers are unaffected by a RESET. Their status
is unknown on POR and unchanged by all other
RESETS. The other registers are forced to a “RESET”
state on Power-on Reset, MCLR, WDT Reset, MCLR
Reset during SLEEP, and by the RESET instruction.
FIGURE 3-1:
Most registers are not affected by a WDT wake-up,
since this is viewed as the resumption of normal operation. Status bits from the RCON register, RI, TO, PD
and POR, are set or cleared differently in different
RESET situations, as indicated in Table 3-2. These bits
are used in software to determine the nature of the
RESET. See Table 3-3 for a full description of the
RESET states of all registers.
A simplified block diagram of the on-chip RESET circuit
is shown in Figure 3-1.
PIC18C601/801 has a MCLR noise filter in the MCLR
Reset path. The filter will detect and ignore small
pulses.
A WDT Reset does not drive MCLR pin low.
SIMPLIFIED BLOCK DIAGRAM OF THE ON-CHIP RESET CIRCUIT
RESET
Instruction
Stack Full/Underflow Reset
Stack
Pointer
External Reset
MCLR
SLEEP
WDT
Module
WDT
Time-out
Reset
VDD Rise
Detect
Power-on Reset
VDD
S
OST/PWRT
OST
Chip_Reset
10-bit Ripple Counter
R
OSC1
Q
PWRT
On-chip
RC OSC(1)
10-bit Ripple Counter
Enable PWRT
Enable OST(2)
Note 1: This is a separate oscillator from the RC oscillator of the CLKI pin.
2: See Table 3-1 for time-out situations.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 29
PIC18C601/801
3.1
Power-on Reset (POR)
3.3
A Power-on Reset pulse is generated on-chip when a
VDD rise is detected. To take advantage of the POR circuitry, connect the MCLR pin directly (or through a
resistor) to VDD. This will eliminate external RC components usually needed to create a Power-on Reset
delay. A minimum rise rate for VDD is specified (parameter D004). For a slow rise time, see Figure 3-2.
When the device starts normal operation (exits the
RESET condition), device operating parameters (voltage, frequency, temperature, etc.) must be met to
ensure operation. If these conditions are not met, the
device must be held in RESET until the operating conditions are met. Power-on Reset may be used to meet
the voltage start-up condition.
FIGURE 3-2:
EXTERNAL POWER-ON
RESET CIRCUIT (FOR
SLOW VDD POWER-UP)
D
R
R1
MCLR
C
PIC18C601/801
Note 1: External Power-on Reset circuit is required only
if the VDD power-up slope is too slow. The diode
D helps discharge the capacitor quickly when
VDD powers down.
2: R < 40 kΩ is recommended to make sure that
the voltage drop across R does not violate the
device’s electrical specification.
3: R1 = 100Ω to 1 kΩ will limit any current flowing
into MCLR from external capacitor C, in the
event of MCLR/VPP pin breakdown due to
Electrostatic Discharge (ESD), or Electrical
Overstress (EOS).
3.2
The Oscillator Start-up Timer (OST) provides 1024
oscillator cycle (from OSC1 input) delay after the
PWRT delay is over (parameter #32). This ensures that
the crystal oscillator or resonator has started and
stabilized.
The OST time-out is invoked only for LP, HS and HS4
modes and only on Power-on Reset or wake-up from
SLEEP.
3.4
PLL Lock Time-out
With the PLL enabled, the time-out sequence following
a Power-on Reset is different from other oscillator
modes. A portion of the Power-up Timer is used to provide a fixed time-out that is sufficient for the PLL to lock
to the main oscillator frequency. This PLL lock time-out
(TPLL) is typically 1 ms and follows the oscillator startup time-out (OST).
3.5
VDD
Oscillator Start-up Timer (OST)
Time-out Sequence
On power-up, the time-out sequence is as follows:
First, PWRT time-out is invoked after the POR time
delay has expired; then, OST is activated. The total
time-out will vary based on oscillator configuration and
the status of the PWRT. For example, in RC mode with
the PWRT disabled, there will be no time-out at all.
Figure 3-3, Figure 3-4, Figure 3-5, Figure 3-6 and
Figure 3-7 depict time-out sequences on power-up.
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the time-outs will expire.
Bringing MCLR high will begin execution immediately
(Figure 3-5). This is useful for testing purposes or to
synchronize more than one PIC18C601/801 device
operating in parallel.
Table 3-2 shows the RESET conditions for some
Special Function Registers, while Table 3-3 shows the
RESET conditions for all registers.
Power-up Timer (PWRT)
The Power-up Timer provides a fixed nominal time-out
(parameter #33), only on power-up from the POR. The
Power-up Timer operates on an internal RC oscillator.
The chip is kept in RESET as long as the PWRT is
active. The PWRT time delay allows VDD to rise to an
acceptable level. PIC18C601/801 devices are available with PWRT enabled or disabled.
The power-up time delay will vary from chip to chip, due
to VDD, temperature and process variation. See DC
parameter #33 for details.
DS39541A-page 30
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 3-1:
TIME-OUT IN VARIOUS SITUATIONS
Power-up(2)
Oscillator
Configuration
PWRTEN = 0
PWRTEN = 1
Wake-up from
SLEEP or
Oscillator Switch(1)
HS with PLL enabled(1)
HS, LP
EC
External RC
72 ms + 1024TOSC
72 ms + 1024TOSC
72 ms
72 ms
1024TOSC
1024TOSC
—
—
1024TOSC + 1 ms
1024TOSC
—
—
Note 1: 1 ms is the nominal time required for the 4X PLL to lock. Maximum time is 2 ms.
2: 72 ms is the nominal Power-up Timer delay.
REGISTER 3-1:
RCON REGISTER BITS AND POSITIONS
R/W-0
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-1
U-0
IPEN
r
—
RI
TO
PD
POR
r
bit 7
TABLE 3-2:
bit 0
STATUS BITS, THEIR SIGNIFICANCE, AND THE INITIALIZATION CONDITION FOR
RCON REGISTER
Program
Counter
RCON
Register
RI
TO
PD
POR
Power-on Reset
00000h
0r-1 110r
1
1
1
0
u
u
MCLR Reset during normal
operation
00000h
0r-u uuur
u
u
u
u
u
u
Software Reset during normal
operation
00000h
0r-0 uuur
0
u
u
u
u
u
Stack Full Reset during normal
operation
00000h
0r-u uu1r
u
u
u
1
u
1
Stack Underflow Reset during normal
operation
00000h
0r-u uu1r
u
u
u
1
1
u
MCLR Reset during SLEEP
00000h
0r-u 10ur
u
1
0
u
u
u
WDT Reset
00000h
0r-u 01ur
u
0
1
u
u
u
WDT Wake-up
PC + 2
ur-u 00ur
u
0
0
u
u
u
ur-u 00ur
u
0
0
u
u
u
Condition
Interrupt wake-up from SLEEP
PC +
2(1)
STKFUL STKUNF
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', r = reserved, maintain ‘0’
Note 1: When the wake-up is due to an interrupt and the GIEH or GIEL bits are set, the PC is loaded with the
interrupt vector (000008h or 000018h).
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 31
PIC18C601/801
FIGURE 3-3:
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD)
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1
FIGURE 3-4:
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2
FIGURE 3-5:
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
DS39541A-page 32
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 3-6:
SLOW RISE TIME (MCLR TIED TO VDD)
5V
VDD
1V
0V
MCLR
INTERNAL POR
TDEADTIME
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
TIME-OUT SEQUENCE ON POR W/ PLL ENABLED (MCLR TIED TO VDD)
FIGURE 3-7:
VDD
MCLR
IINTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
TPLL
OST TIME-OUT
PLL TIME-OUT
INTERNAL RESET
TOST = 1024 clock cycles.
TPLL ≈ 2 ms max. First three stages of the PWRT timer.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 33
PIC18C601/801
TABLE 3-3:
Register
INITIALIZATION CONDITIONS FOR ALL REGISTERS
Applicable
Devices
Power-on Reset
MCLR Reset
WDT Reset
Reset Instruction
Stack Over/Underflow Reset
Wake-up via WDT or
Interrupt
TOSU
601
801
---0 0000
---0 0000
---u uuuu(3)
TOSH
601
801
0000 0000
0000 0000
uuuu uuuu(3)
TOSL
601
801
0000 0000
0000 0000
uuuu uuuu(3)
STKPTR
601
801
00-0 0000
00-0 0000
uu-u uuuu(3)
PCLATU
601
801
---0 0000
---0 0000
---u uuuu
PCLATH
601
801
0000 0000
0000 0000
uuuu uuuu
PCL
601
801
0000 0000
0000 0000
PC + 2(2)
TBLPTRU
601
801
--00 0000
--00 0000
--uu uuuu
TBLPTRH
601
801
0000 0000
0000 0000
uuuu uuuu
TBLPTRL
601
801
0000 0000
0000 0000
uuuu uuuu
TABLAT
601
801
0000 0000
0000 0000
uuuu uuuu
PRODH
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
PRODL
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
INTCON
601
801
0000 000x
0000 000u
uuuu uuuu(1)
INTCON2
601
801
1111 -1-1
1111 -1-1
uuuu -u-u(1)
INTCON3
601
801
11-0 0-00
11-0 0-00
uu-u u-uu(1)
INDF0
601
801
(Note 5)
(Note 5)
(Note 5)
POSTINC0
601
801
(Note 5)
(Note 5)
(Note 5)
POSTDEC0
601
801
(Note 5)
(Note 5)
(Note 5)
PREINC0
601
801
(Note 5)
(Note 5)
(Note 5)
PLUSW0
601
801
(Note 5)
(Note 5)
(Note 5)
FSR0H
601
801
---- 0000
---- 0000
---- uuuu
FSR0L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
WREG
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
INDF1
601
801
(Note 5)
(Note 5)
(Note 5)
POSTINC1
601
801
(Note 5)
(Note 5)
(Note 5)
POSTDEC1
601
801
(Note 5)
(Note 5)
(Note 5)
PREINC1
601
801
(Note 5)
(Note 5)
(Note 5)
PLUSW1
601
801
(Note 5)
(Note 5)
(Note 5)
FSR1H
601
801
---- 0000
---- 0000
---- uuuu
FSR1L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
BSR
601
801
---- 0000
---- 0000
---- uuuu
INDF2
601
801
(Note 5)
(Note 5)
(Note 5)
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ’0’, q = value depends on condition,
r = reserved, maintain ‘0’
Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (00008h or 00018h).
3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH, and TOSL are
updated with the current value of the PC. The SKPTR is modified to point to the next location in the
hardware stack.
4: See Table 3-2 for RESET value for specific condition.
5: This is not a physical register. It is an indirect pointer that addresses another register. The contents
returned is the value contained in the addressed register.
DS39541A-page 34
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 3-3:
Register
INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Applicable
Devices
Power-on Reset
MCLR Reset
WDT Reset
Reset Instruction
Stack Over/Underflow Reset
Wake-up via WDT or
Interrupt
POSTINC2
601
801
(Note 5)
(Note 5)
(Note 5)
POSTDEC2
601
801
(Note 5)
(Note 5)
(Note 5)
PREINC2
601
801
(Note 5)
(Note 5)
(Note 5)
PLUSW2
601
801
(Note 5)
(Note 5)
(Note 5)
FSR2H
601
801
---- 0000
---- 0000
---- uuuu
FSR2L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
STATUS
601
801
---x xxxx
---u uuuu
---u uuuu
TMR0H
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
TMR0L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
T0CON
601
801
1111 1111
1111 1111
uuuu uuuu
OSCCON
601
801
--00 0-00
--uu u-u0
--uu u-uu
LVDCON
601
801
--00 0101
--00 0101
--uu uuuu
WDTCON
601
801
---- 1111
---- uuuu
---- uuuu
RCON(4)
601
801
0r-1 11qr
0r-1 qqur
ur-u qqur
TMR1H
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
TMR1L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
T1CON
601
801
0-00 0000
u-uu uuuu
u-uu uuuu
TMR2
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
PR2
601
801
1111 1111
1111 1111
1111 1111
T2CON
601
801
-000 0000
-000 0000
-uuu uuuu
SSPBUF
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
SSPADD
601
801
0000 0000
0000 0000
uuuu uuuu
SSPSTAT
601
801
0000 0000
0000 0000
uuuu uuuu
SSPCON1
601
801
0000 0000
0000 0000
uuuu uuuu
SSPCON2
601
801
0000 0000
0000 0000
uuuu uuuu
ADRESH
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
ADRESL
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
ADCON0
601
801
--00 0000
--00 0000
--uu uuuu
ADCON1
601
801
-000 0000
-000 0000
-uuu uuuu
ADCON2
601
801
0--- -000
0--- -000
u--- -uuu
CCPR1H
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCPR1L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCP1CON
601
801
--00 0000
--00 0000
--uu uuuu
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ’0’, q = value depends on condition,
r = reserved, maintain ‘0’
Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (00008h or 00018h).
3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH, and TOSL are
updated with the current value of the PC. The SKPTR is modified to point to the next location in the
hardware stack.
4: See Table 3-2 for RESET value for specific condition.
5: This is not a physical register. It is an indirect pointer that addresses another register. The contents
returned is the value contained in the addressed register.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 35
PIC18C601/801
TABLE 3-3:
Register
INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Applicable
Devices
Power-on Reset
MCLR Reset
WDT Reset
Reset Instruction
Stack Over/Underflow Reset
Wake-up via WDT or
Interrupt
CCPR2H
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCPR2L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCP2CON
601
801
--00 0000
--00 0000
--uu uuuu
TMR3H
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
TMR3L
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
T3CON
601
801
0000 0000
uuuu uuuu
uuuu uuuu
SPBRG
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
RCREG
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
TXREG
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
TXSTA
601
801
0000 -01x
0000 -01u
uuuu -uuu
RCSTA
601
801
0000 000x
0000 000u
uuuu uuuu
IPR2
601
801
-1-- 1111
-1-- 1111
-u-- uuuu
PIR2
601
801
-1-- 0000
-1-- 0000
-u-- uuuu(1)
PIE2
601
801
-1-- 0000
-1-- 0000
-u-- uuuu
IPR1
601
801
1111 1111
1111 1111
uuuu uuuu
601
801
-111 1111
-111 1111
-uuu uuuu
601
801
0000 0000
0000 0000
uuuu uuuu(1)
601
801
-000 0000
-000 0000
-uuu uuuu(1)
601
801
0000 0000
0000 0000
uuuu uuuu
601
801
-000 0000
-000 0000
-uuu uuuu
MEMCON
601
801
0000 --00
0000 --00
uuuu --uu
TRISJ
601
801
1111 1111
1111 1111
uuuu uuuu
PIR1
PIE1
TRISH
601
801
1111 1111
1111 1111
uuuu uuuu
TRISG
601
801
---1 1111
---1 1111
---u uuuu
TRISF
601
801
1111 1111
1111 1111
uuuu uuuu
TRISE
601
801
1111 1111
1111 1111
uuuu uuuu
TRISD
601
801
1111 1111
1111 1111
uuuu uuuu
TRISC
601
801
1111 1111
1111 1111
uuuu uuuu
TRISB
601
801
1111 1111
1111 1111
uuuu uuuu
TRISA
601
801
--11 1111
--11 1111
--uu uuuu
LATG
601
801
---x xxxx
---u uuuu
---u uuuu
LATF
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATE
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ’0’, q = value depends on condition,
r = reserved, maintain ‘0’
Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (00008h or 00018h).
3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH, and TOSL are
updated with the current value of the PC. The SKPTR is modified to point to the next location in the
hardware stack.
4: See Table 3-2 for RESET value for specific condition.
5: This is not a physical register. It is an indirect pointer that addresses another register. The contents
returned is the value contained in the addressed register.
DS39541A-page 36
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 3-3:
Register
INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Applicable
Devices
Power-on Reset
MCLR Reset
WDT Reset
Reset Instruction
Stack Over/Underflow Reset
Wake-up via WDT or
Interrupt
LATD
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATC
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATB
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATA
601
801
--xx xxxx
--uu uuuu
--uu uuuu
PORTJ
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTH
601
801
0000 xxxx
0000 uuuu
uuuu uuuu
PORTG
601
801
---x xxxx
---u uuuu
---u uuuu
PORTF
601
801
xxxx x000
uuuu u000
uuuu uuuu
PORTE
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTD
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTC
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTB
601
801
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTA
601
801
--0x 0000
--0u 0000
--uu uuuu
CSEL2
601
801
1111 1111
uuuu uuuu
uuuu uuuu
CSELIO
601
801
1111 1111
uuuu uuuu
uuuu uuuu
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ’0’, q = value depends on condition,
r = reserved, maintain ‘0’
Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (00008h or 00018h).
3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH, and TOSL are
updated with the current value of the PC. The SKPTR is modified to point to the next location in the
hardware stack.
4: See Table 3-2 for RESET value for specific condition.
5: This is not a physical register. It is an indirect pointer that addresses another register. The contents
returned is the value contained in the addressed register.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 37
PIC18C601/801
NOTES:
DS39541A-page 38
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
4.0
MEMORY ORGANIZATION
There are two memory blocks in PIC18C601/801
devices. These memory blocks are:
• Program Memory
• Data Memory
Each block has its own bus so that concurrent access
can occur.
4.1
Program Memory Organization
PIC18C601/801 devices have a 21-bit program
counter that is capable of addressing up to 2 Mbyte of
external program memory space. The PIC18C601 has
an external program memory address space of 256
Kbytes. Any program fetch or TBLRD from a program
location greater than 256K will return all NOPs. The
PIC18C801 has an external program memory address
space of 2Mbytes. Refer to Section 5.0 (“External
Memory Interface”) for additional details.
The RESET vector address is mapped to 000000h and
the interrupt vector addresses are at 000008h and
000018h. PIC18C601/801 devices have a 31-level stack
to store the program counter values during subroutine
calls and interrupts. Figure 4-1 shows the program
memory map and stack for PIC18C601. Figure 4-2
shows the program memory map and stack for the
PIC18C801.
4.1.1
“BOOT RAM” PROGRAM MEMORY
PIC18C601/801 devices have a provision for configuring the last 512 bytes of general purpose user RAM as
program memory, called “Boot RAM”. This is achieved
by configuring the PGRM bit in the MEMCON register
to ‘1’. (Refer to Section 5.0, “External Memory Interface” for more information.) When the PGRM bit is ‘1’,
the RAM located in data memory locations 400h
through 5FFh (bank 4 through 5) is mapped to program
memory locations 1FFE00h to 1FFFFFh.
When configured as program memory, the Boot RAM is
to be used as a temporary “boot loader” for programming purposes. It can only be used for program execution. A read from locations 400h to 5FFh in data
memory returns all ‘0’s. Any attempt to write this RAM
as data memory when PGRM = 1, does not modify any
of these locations. TBLWT instructions to these locations will cause writes to occur on the external memory
bus. The boot RAM program memory cannot be modified using TBLWT instruction. TBLRD instructions from
boot RAM will read memory located on the external
memory bus, not from the on-board RAM. Constants
that are stored in boot RAM are retrieved using the
RETLW instruction.
The default RESET state (power-up) for the PGRM bit
is ‘0’, which configures 1.5K of data RAM and all program memory as external. The PGRM bit can be set
and cleared in the software.
When execution takes place from “Boot RAM”, the
external system bus and all of its control signals will be
deactivated. If execution takes place from outside of
“Boot RAM”, the external system bus and all of its control signals are activated again.
Figure 4-3 and Figure 4-4 show the program memory
map and stack for PIC18C601 and PIC18C801, when
the PGRM bit is set.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 39
PIC18C601/801
FIGURE 4-1:
PROGRAM MEMORY MAP
AND STACK FOR
PIC18C601 (PGRM = 0)
FIGURE 4-2:
PC<20:0>
PROGRAM MEMORY MAP
AND STACK FOR
PIC18C801 (PGRM = 0)
PC<20:0>
21
21
Stack Level 1
Stack Level 1
•
•
•
•
•
•
Stack Level 31
Stack Level 31
RESET Vector
RESET Vector
0000h
0000h
High Priority Interrupt Vector 0008h
High Priority Interrupt Vector 0008h
Low Priority Interrupt Vector
Low Priority Interrupt Vector
3FFFFh
40000h
0018h
User Memory Space
External
Program Memory
User Memory Space
0018h
External
Program Memory
Read ’0’
1FFFFFh
DS39541A-page 40
1FFFFFh
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 4-3:
PROGRAM MEMORY MAP AND STACK FOR PIC18C601 (PGRM = 1)
PC<20:0>
21
Stack Level 1
•
•
•
Stack Level 31
RESET Vector
0000h
High Priority Interrupt Vector 0008h
0018h
External
Program Memory
03FFFFh
040000h
User Memory Space
Low Priority Interrupt Vector
Read ’0’
1FFE00h
1FFDFFh
1FFE00h
1FFFFFh
1FFFFFh
On-Chip
Boot RAM
INTERNAL MEMORY
 2001 Microchip Technology Inc.
EXTERNAL MEMORY
Advance Information
DS39541A-page 41
PIC18C601/801
FIGURE 4-4:
PROGRAM MEMORY MAP AND STACK FOR PIC18C801 (PGRM = 1)
PC<20:0>
21
Stack Level 1
•
•
•
Stack Level 31
RESET Vector
0000h
High Priority Interrupt Vector 0008h
0018h
User Memory Space
Low Priority Interrupt Vector
External
Program Memory
1FFDFFh
1FFE00h
1FFE00h
External
Table Memory
On-Chip
Boot RAM
1FFFFFh
1FFFFFh
INTERNAL MEMORY
DS39541A-page 42
EXTERNAL MEMORY
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
4.1.2
BOOT LOADER
4.2.1
When configured as Program Memory, Boot RAM can
be used as a temporary “Boot Loader” for programming
purposes. If an external memory device is used as program memory, any updates performed by the user program will have to be performed in the “Boot RAM”,
because the user program cannot program and fetch
from external memory, simultaneously.
A typical boot loader execution and external memory
programming sequence would be as follows:
• The boot loader program is transferred from the
external program memory to the last 2 banks of
data RAM by TBLRD and MOVWF instructions.
• Once the “boot loader” program is loaded into
internal memory and verified, open combination
lock and set PGRM bit to configure the data RAM
into program RAM.
• Jump to beginning of Boot code in Boot RAM.
Program execution begins in Boot RAM to begin
programming the external memory. System bus
changes to an inactive state.
• Boot loader program performs the necessary
external TBLWT and TBLWRD instructions to
perform programming functions.
• When the boot loader program is finished programming external memory, jump to known valid
external program memory location and clear
PGRM bit in MEMCON register to set Boot RAM
as data memory, or reset the part.
4.2
Return Address Stack
TOP-OF-STACK ACCESS
The top of the stack is readable and writable. Three
register locations, TOSU, TOSH and TOSL, allow
access to the contents of the stack location indicated by
the STKPTR register. This allows users to implement a
software stack, if necessary. After a CALL, RCALL or
interrupt, the software can read the pushed value by
reading the TOSU, TOSH and TOSL registers. These
values can be placed on a user defined software stack.
At return time, the software can replace the TOSU,
TOSH and TOSL and do a return.
The user should disable the global interrupt enable bits
during this time to prevent inadvertent stack operations.
4.2.2
RETURN STACK POINTER
(STKPTR)
The STKPTR register contains the stack pointer value,
the STKFUL (stack full) status bit, and the STKUNF
(stack underflow) status bits. Register 4-1 shows the
STKPTR register. The value of the stack pointer can be
0 through 31. The stack pointer increments when values are pushed onto the stack and decrements when
values are popped off the stack. At RESET, the stack
pointer value will be 0. The user may read and write the
stack pointer value. This feature can be used by a Real
Time Operating System for return stack maintenance.
After the PC is pushed onto the stack 31 times (without
popping any values off the stack), the STKFUL bit is
set. The STKFUL bit can only be cleared in software or
by a POR. Any subsequent push operation that causes
stack overflow will be ignored.
The return address stack allows any combination of up to
31 program calls and interrupts to occur. The PC (Program Counter) is pushed onto the stack when a PUSH,
CALL or RCALL instruction is executed, or an interrupt is
acknowledged. The PC value is pulled off the stack on a
RETURN, RETLW or a RETFIE instruction. PCLATU and
PCLATH are not affected by any of the return instructions.
The action that takes place when the stack becomes
full, depends on the state of STVREN (stack overflow
RESET enable) configuration bit in CONFIG4L register. Refer to Section 4.2.4 for more information. If
STVREN is set (default), stack over/underflow will set
the STKFUL bit, and reset the device. The STKFUL bit
will remain set and the stack pointer will be set to 0.
The stack operates as a 31-word by 21-bit stack memory
and a five-bit stack pointer, with the stack pointer initialized to 00000b after all RESETS. There is no RAM associated with stack pointer 00000b. This is only a RESET
value. During a CALL type instruction, causing a push
onto the stack, the stack pointer is first incremented and
the RAM location pointed to by the stack pointer is written
with the contents of the PC. During a RETURN type
instruction, causing a pop from the stack, the contents of
the RAM location indicated by the STKPTR is transferred
to the PC and then the stack pointer is decremented.
If STVREN is cleared, the STKFUL bit will be set on the
31st push and the stack pointer will increment to 31. All
subsequent push attempts will be ignored and
STKPTR remains at 31.
When the stack has been popped enough times to
unload the stack, the next pop will return a value of zero
to the PC and sets the STKUNF bit, while the stack
pointer remains at 0. The STKUNF bit will remain set
until cleared in software, or a POR occurs.
Note:
The stack space is not part of either program or data
space. The stack pointer is readable and writable, and
the data on the top of the stack is readable and writable
through SFR registers. Status bits STKOVF and
STKUNF in STKPTR register, indicate whether stack
over/underflow has occurred or not.
 2001 Microchip Technology Inc.
Advance Information
Returning a value of zero to the PC on an
underflow has the effect of vectoring the
program to the RESET vector, where the
stack conditions can be verified and appropriate actions can be taken.
DS39541A-page 43
PIC18C601/801
REGISTER 4-1:
STKPTR - STACK POINTER REGISTER
R/C-0
STKFUL
bit 7
R/C-0
STKUNF
U-0
—
R/W-0
SP4
bit 7
STKFUL: Stack Full Flag bit
1 = Stack became full or overflowed
0 = Stack has not become full or overflowed
bit 6
STKUNF: Stack Underflow Flag bit
1 = Stack underflow occurred
0 = Stack underflow did not occur
bit 5
Unimplemented: Read as '0'
bit 4-0
SP4:SP0: Stack Pointer Location bits
Note:
R/W-0
SP3
R/W-0
SP2
R/W-0
SP1
R/W-0
SP0
bit 0
Bit 7 and bit 6 can only be cleared in user software, or by a POR.
Legend:
FIGURE 4-5:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
C = Clearable bit
RETURN ADDRESS STACK AND ASSOCIATED REGISTERS
Return Address Stack
11111
11110
11101
TOSU
00h
TOSH
1Ah
STKPTR<4:0>
00010
TOSL
34h
Top-of-Stack
00011
001A34h 00010
000D58h 00001
000000h 00000(1)
Note 1: No RAM is associated with this address; always maintained ‘0’s.
DS39541A-page 44
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
4.2.3
PUSH AND POP INSTRUCTIONS
4.3
Fast Register Stack
Since the Top-of-Stack (TOS) is readable and writable,
the ability to push values onto the stack and pop values
off the stack, without disturbing normal program execution, is a desirable option. To push the current PC value
onto the stack, a PUSH instruction can be executed.
This will increment the stack pointer and load the current PC value onto the stack. TOSU, TOSH and TOSL
can then be modified to place a return address on the
stack.
A “fast return” option is available for interrupts and calls.
A fast register stack is provided for the STATUS, WREG
and BSR registers, and is only one layer in depth. The
stack is not readable or writable and is loaded with the
current value of the corresponding register when the
processor vectors for an interrupt. The values in the fast
register stack are then loaded back into the working registers, if the fast return instruction is used to return
from the interrupt.
The POP instruction discards the current TOS by decrementing the stack pointer. The previous value pushed
onto the stack then becomes the TOS value.
A low or high priority interrupt source will push values
into the stack registers. If both low and high priority
interrupts are enabled, the stack registers cannot be
used reliably for low priority interrupts. If a high priority
interrupt occurs while servicing a low priority interrupt,
the stack register values stored by the low priority
interrupt will be overwritten.
4.2.4
STACK FULL/UNDERFLOW RESETS
These RESETS are enabled/disabled by programming
the STVREN configuration bit in CONFIG4L register.
When the STVREN bit is disabled, a full or underflow
condition will set the appropriate STKFUL or STKUNF
bit, but not cause a RESET. When the STVREN bit is
enabled, a full or underflow will set the appropriate
STKFUL or STKUNF bit and then cause a RESET. The
STKFUL or STKUNF bits are only cleared by the user
software or a POR.
If high priority interrupts are not disabled during low priority interrupts, users must save the key registers in
software during a low priority interrupt.
If no interrupts are used, the fast register stack can be
used to restore the STATUS, WREG and BSR registers
at the end of a subroutine call. To use the fast register
stack for a subroutine call, a fast call instruction
must be executed.
Example 4-1 shows a source code example that uses
the fast register stack.
EXAMPLE 4-1:
CALL SUB1, FAST
FAST REGISTER STACK
CODE EXAMPLE
;STATUS, WREG, BSR
;SAVED IN FAST REGISTER
;STACK
•
•
•
•
•
RETURN FAST
SUB1
 2001 Microchip Technology Inc.
Advance Information
;RESTORE VALUES SAVED
;IN FAST REGISTER STACK
DS39541A-page 45
PIC18C601/801
4.4
PCL, PCLATH and PCLATU
The contents of PCLATH and PCLATU will be transferred to the program counter by an operation that
writes PCL. Similarly, the upper two bytes of the program counter will be transferred to PCLATH and
PCLATU by an operation that reads PCL. This is useful
for computed offsets to the PC (See Section 4.8.1).
The program counter (PC) specifies the address of the
instruction to fetch for execution. The PC is 21-bits
wide. The low byte is called the PCL register. This register is readable and writable. The high byte is called
the PCH register. This register contains the PC<15:8>
bits and is not directly readable or writable. Updates to
the PCH register may be performed through the
PCLATH register. The upper byte is called PCU. This
register contains the PC<20:16> bits and is not directly
readable or writable. Updates to the PCU register may
be performed through the PCLATU register.
4.5
The clock input (from OSC1 or PLL output) is internally
divided by four to generate four non-overlapping
quadrature clocks, namely Q1, Q2, Q3 and Q4. Internally, the program counter (PC) is incremented every
Q1, the instruction is fetched from the program memory
and latched into the instruction register in Q4. The
instruction is decoded and executed during the following Q1 through Q4. The clocks and instruction execution flow are shown in Figure 4-6.
The PC addresses bytes in the program memory. To
prevent the PC from becoming misaligned with word
instructions, the LSb of the PCL is fixed to a value of ’0’.
The PC increments by 2 to address sequential instructions in the program memory.
The CALL, RCALL, GOTO and program branch
instructions write to the program counter directly. For
these instructions, the contents of PCLATH and
PCLATU are not transferred to the program counter.
FIGURE 4-6:
Clocking Scheme/Instruction
Cycle
CLOCK/INSTRUCTION CYCLE
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
OSC1
Q1
Q2
Internal
Phase
Clock
Q3
Q4
PC
OSC2/CLKOUT
(RC mode)
DS39541A-page 46
PC
Fetch INST (PC)
Execute INST (PC-2)
PC+2
Fetch INST (PC+2)
Execute INST (PC)
Advance Information
PC+4
Fetch INST (PC+4)
Execute INST (PC+2)
 2001 Microchip Technology Inc.
PIC18C601/801
4.6
Instruction Flow/Pipelining
4.7
Instructions in Program Memory
An “Instruction Cycle” consists of four Q cycles (Q1,
Q2, Q3 and Q4). The instruction fetch and execute are
pipelined, such that fetch takes one instruction cycle,
while decode and execute takes another instruction
cycle. However, due to the pipelining, each instruction
effectively executes in one cycle. If an instruction
causes the program counter to change (e.g., GOTO),
two cycles are required to complete the instruction
(Example 4-2).
The program memory is addressed in bytes. Instructions are stored as two bytes or four bytes in program
memory. The Least Significant Byte of an instruction
word is always stored in a program memory location
with an even address (LSB = ’0’). Figure 4-1 shows an
example of how instruction words are stored in the program memory. To maintain alignment with instruction
boundaries, the PC increments in steps of 2 and the
LSB will always read ’0’ (see Section 4.4).
A fetch cycle begins with the program counter (PC)
incrementing in Q1.
The CALL and GOTO instructions have an absolute program memory address embedded into the instruction.
Since instructions are always stored on word boundaries, the data contained in the instruction is a word
address. The word address is written to PC<20:1>,
which accesses the desired byte address in program
memory. Instruction #2 in Figure 4-1 shows how the
instruction “GOTO 0x06” is encoded in the program
memory. Program branch instructions that encode a
relative address offset operate in the same manner.
The offset value stored in a branch instruction represents the number of single word instructions by which
the PC will be offset. Section 20.0 provides further
details of the instruction set.
In the execution cycle, the fetched instruction is latched
into the “Instruction Register” (IR) in cycle Q1. This
instruction is then decoded and executed during the
Q2, Q3, and Q4 cycles. Data memory is read during Q2
(operand read) and written during Q4 (destination
write).
EXAMPLE 4-2:
INSTRUCTION PIPELINE FLOW
1. MOVLW 55h
TCY0
TCY1
Fetch 1
Execute 1
Fetch 2
2. MOVWF PORTB
TCY3
TCY4
TCY5
Execute 2
Fetch 3
3. BRA SUB_1
4. BSF
TCY2
Execute 3
Fetch 4
PORTA, BIT3 (Forced NOP)
Flush
Fetch SUB_1 Execute SUB_1
5. Instruction @ address SUB_1
All instructions are single cycle, except for any program branches. These take two cycles, since the fetch instruction
is “flushed” from the pipeline, while the new instruction is being fetched and then executed.
TABLE 4-1:
INSTRUCTIONS IN PROGRAM MEMORY
Instruction
Opcode
Memory
Address
—
—
000007h
0E55h
55h
000008h
—
MOVLW 055h
GOTO 000006h
EF03h, F000h
MOVFF 123h, 456h
—
 2001 Microchip Technology Inc.
C123h, F456h
—
Advance Information
0Eh
000009h
03h
00000Ah
EFh
00000Bh
00h
00000Ch
F0h
00000Dh
23h
00000Eh
C1h
00000Fh
56h
000010h
F4h
000011h
—
000012h
DS39541A-page 47
PIC18C601/801
4.7.1
TWO-WORD INSTRUCTIONS
The offset value (value in WREG) specifies the number
of bytes that the program counter should advance.
PIC18C601/801 devices have four two-word instructions: MOVFF, CALL, GOTO and LFSR. The second
word of these instructions has the four MSB’s set to 1’s
and is a special kind of NOP instruction. The lower 12
bits of the second word contain data to be used by the
instruction. If the first word of the instruction is executed, the data in the second word is accessed. If the
second word of the instruction is executed by itself (first
word was skipped), it will execute as a NOP. This action
is necessary when the two-word instruction is preceded
by a conditional instruction that changes the PC and
skips one instruction. A program example that demonstrates this concept is shown in Example 4-3. Refer to
Section 19.0 for further details of the instruction set.
4.8
In this method, only one data byte may be stored in
each instruction location and room on the return
address stack is required.
Warning: The LSb of the PCL is fixed to a value of ‘0’.
Hence, computed GOTO to an odd address
is not possible.
4.8.2
A better method of storing data in program memory
allows 2 bytes of data to be stored in each instruction
location.
Lookup table data may be stored as 2 bytes per program word by using table reads and writes. The table
pointer (TBLPTR) specifies the byte address and the
table latch (TABLAT) contains the data that is read
from, or written to, program memory. Data is transferred to/from program memory one byte at a time.
Lookup Tables
Lookup tables are implemented two ways:
• Computed GOTO
• Table Reads
4.8.1
A description of the Table Read/Table Write operation
is shown in Section 6.0.
COMPUTED GOTO
Note:
A computed GOTO is accomplished by adding an offset
to the program counter (ADDWF PCL).
A lookup table can be formed with an ADDWF PCL
instruction and a group of RETLW 0xnn instructions.
WREG is loaded with an offset into the table, before executing a call to that table. The first instruction of the called
routine is the ADDWF PCL instruction. The next instruction executed will be one of the RETLW 0xnn instructions that returns the value 0xnn to the calling function.
EXAMPLE 4-3:
TABLE READS/TABLE WRITES
If execution is taking place from Boot RAM
Program Memory, RETLW instructions
must be used to read lookup values from
the Boot RAM itself.
Two-Word Instructions
CASE 1:
Object Code
Source Code
0110 0110 0000 0000
TSTFSZ
REG1
; is RAM location 0?
1100 0001 0010 0011
MOVFF
REG1, REG2
1111 0100 0101 0110
0010 0100 0000 0000
; No, execute 2-word instruction
; 2nd operand holds address of REG2
ADDWF
REG3
; continue code
CASE 2:
Object Code
Source Code
0110 0110 0000 0000
TSTFSZ
REG1
1100 0001 0010 0011
MOVFF
REG1, REG2
1111 0100 0101 0110
0010 0100 0000 0000
DS39541A-page 48
; is RAM location 0?
; Yes
; 2nd operand executed as NOP
ADDWF
REG3
; continue code
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
4.9
Data Memory Organization
The data memory is implemented as static RAM. Each
register in the data memory has a 12-bit address, allowing up to 4096 bytes of data memory. Figure 4-8 shows
the data memory organization for PIC18C601/801
devices.
The data memory map is divided into banks that contain 256 bytes each. The lower four bits of the Bank
Select Register (BSR<3:0>) select which bank will be
accessed. The upper 4 bits for the BSR are not implemented.
The data memory contains Special Function Registers
(SFR) and General Purpose Registers (GPR). The
SFR’s are used for control and status of the controller
and peripheral functions, while GPR’s are used for data
storage and scratch pad operations in the user’s application. The SFR’s start at the last location of Bank 15
(0FFFh) and grow downwards. GPR’s start at the first
location of Bank 0 and grow upwards. Any read of an
unimplemented location will read as ’0’s.
GPR banks 4 and 5 serve as a Program Memory called
“Boot RAM”, when PGRM bit in MEMCON is set. When
PGRM bit is set, any read from “Boot RAM” returns ‘0’s,
while any write to it is ignored.
The entire data memory may be accessed directly or
indirectly. Direct addressing may require the use of the
BSR register. Indirect addressing requires the use of a
File Select Register (FSR). Each FSR holds a 12-bit
address value that can be used to access any location
in the Data Memory map without banking.
The instruction set and architecture allow operations
across all banks. This may be accomplished by indirect
addressing, or by the use of the MOVFF instruction. The
MOVFF instruction is a two-word/two-cycle instruction
that moves a value from one register to another.
To ensure that commonly used registers (SFRs and
select GPRs) can be accessed in a single cycle,
regardless of the current BSR values, an Access Bank
is implemented. A segment of Bank 0 and a segment of
Bank 15 comprise the Access bank. Section 4.10 provides a detailed description of the Access bank.
4.9.1
GENERAL PURPOSE REGISTER
FILE
The register file can be accessed either directly or indirectly. Indirect addressing operates through the File
Select Registers (FSR). The operation of indirect
addressing is shown in Section 4.12.
PIC18C601/801 devices have banked memory in the
GPR area. GPRs are not initialized by a Power-on
Reset and are unchanged on all other RESETS.
Data RAM is available for use as GPR registers by all
instructions. Bank 15 (0F80h to 0FFFh) contains
SFR’s. All other banks of data memory contain GPR
registers starting with bank 0.
4.9.2
SPECIAL FUNCTION REGISTERS
The Special Function Registers (SFRs) are registers
used by the CPU and Peripheral Modules for controlling the desired operation of the device. These registers are implemented as static RAM. A list of these
registers is given in Table 4-2.
The SFR’s can be classified into two sets: those associated with the “core” function and those related to the
peripheral functions. Those registers related to the
“core” are described in this section, while those related
to the operation of the peripheral features are
described in the section of that peripheral feature.
The SFRs are typically distributed among the peripherals whose functions they control.
The unused SFR locations are unimplemented and
read as '0's. See Table 4-2 for addresses for the SFRs.
4.9.3
SECURED ACCESS REGISTERS
PIC18C601/801 devices contain software programming options for safety critical peripherals. Because
these safety critical peripherals can be programmed in
software, registers used to control these peripherals
are given limited access by the user code. This way,
errant code will not accidentally change settings in
peripherals that could cause catastrophic results.
The registers that are considered safety critical are the
Watchdog Timer register (WDTCON), the External
Memory Control register (MEMCON), the Oscillator
Control register (OSCCON) and the Chip Select registers (CSSEL2 and CSELIO).
Two bits called Combination Lock (CMLK) bits, located
in the lower two bits of the PSPCON register, must be
set in sequence by user code to gain access to
Secured Access registers.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 49
PIC18C601/801
REGISTER 4-2:
PSPCON REGISTER
U-0
U-0
U-0
U-0
U-0
U-0
W-0
W-0
—
—
—
—
—
—
CMLK1
CMLK0
bit 7
bit 0
bit 7-2
Unimplemented: Read as '0'
bit 1-0
CMLK<1:0>: Combination Lock bits
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
The Combination Lock bits must be set sequentially,
meaning that as soon as Combination Lock bit CMLK1
is set, the second Combination Lock bit CMLK0 must be
set on the following instruction cycle. If user waits more
than one machine cycle to set the second bit after setting the first, both bits will automatically be cleared in
hardware and the lock will remain closed. To satisfy this
condition, all interrupts must be disabled before attempting to unlock the Combination Lock. Once secured registers are modified, interrupts may be re-enabled.
Each instruction must only modify one combination lock
bit at a time. This means, user code must use the BSF
instruction to set CMLK bits in the PSPCON register.
Note:
When the Combination Lock is opened, the user will
have three instruction cycles to modify the safety critical register of choice. After three instruction cycles
have expired, the CMLK bits are cleared, the lock will
close and the user will have to set the CMLK bits again,
in order to open the lock. Since there are only three
instruction cycles allowed after the Combination Lock is
opened, if a subroutine is used to unlock Combination
Lock bits, user code must preload WREG with the
desired value, call unlock subroutine, and write to the
desired safety critical register itself.
Note:
The Combination Lock bits are write-only
bits. These bits will always return ‘0’ when
read.
EXAMPLE 4-4:
x = Bit is unknown
Successive attempts to unlock the Combination Lock must be separated by at least
three instruction cycles.
COMBINATION UNLOCK SUBROUTINE EXAMPLE CODE
MOVLW 5Ah
BCF INTCON, GIE
CALL UNLOCK
;
;
;
;
Preload WREG with data to be stored in a safety critical register
Disable all interrupts
Now unlock it
Write must take place in next instruction cycle
MOVWF OSCCON
BSF INTCON, GIE
•
•
UNLOCK
BSF PSPCON, CMLK1
BSF PSPCON, CMLK0
RETURN
•
•
DS39541A-page 50
; Lock is closed
; Re-enable interrupts
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
EXAMPLE 4-5:
COMBINATION UNLOCK MACRO EXAMPLE CODE
UNLOCK_N_MODIFY @REG
MACRO
BCF INTCON,
BSF PSPCON,
BSF PSPCON,
MOVWF @REG
BSF INTCON,
ENDM
GIE
CMLK1
CMLK0
; Disable interrupts
; Modify given register
; Enable interrupts
GIE
•
•
MOVLW 5Ah
UNLOCK_N_MODIFY OSCCON
FIGURE 4-7:
THE DATA MEMORY MAP FOR PIC18C801/601 (PGRM = 0)
BSR<3:0>
= 0000b
= 0001b
Data Memory Map
00h
Access GPR’s
FFh
00h
GPR
Bank 0
FFh
00h
Bank 2
= 0100b
1FFh
200h
GPR
2FFh
300h
FFh
00h
Bank 3
GPR
FFh
00h
Bank 4
3FFh
400h
GPR
GPR
Bank 5
5FFh
FFh
= 0110b
= 1110b
= 1111b
Bank 6
to
Bank 14
Unused
Read ’00h’
00h
Unused
FFh
Access SFR’s
Bank 15
 2001 Microchip Technology Inc.
Access RAM Bank
4FFh
500h
FFh
00h
= 0101b
000h
07Fh
080h
0FFh
100h
GPR
Bank 1
= 0010b
= 0011b
; Preload WREG for OSCCON register
; Modify OSCCON
EFFh
F00h
F7Fh
F80h
FFFh
Advance Information
00h
Access Bank Low
(GPR’s)
7Fh
Access Bank High 80h
(SFR’s)
FFh
When a = 0,
the BSR is ignored and this
Access RAM bank is used.
The first 128 bytes are General
Purpose RAM (from Bank 0).
The next 128 bytes are Special
Function Registers (from
Bank 15).
When a = 1,
the BSR is used to specify
the RAM location that the
instruction uses.
DS39541A-page 51
PIC18C601/801
FIGURE 4-8:
DATA MEMORY MAP FOR PIC18C601/801 (PGRM = 1)
BSR<3:0>
= 0000b
= 0001b
Data Memory Map
00h
Access GPR’s
FFh
00h
GPR
Bank 0
GPR
Bank 1
FFh
00h
= 0010b
Bank 2
= 0011b
000h
07Fh
080h
0FFh
100h
1FFh
200h
GPR
2FFh
300h
FFh
00h
Bank 3
GPR
3FFh
FFh
Access RAM Bank
00h
Access Bank Low
(GPR’s)
7Fh
Access Bank High 80h
(SFR’s)
FFh
= 0100b
= 1110b
= 1111b
DS39541A-page 52
Bank 4
to
Bank 14
Unused
Read ’00h’
00h
Unused
FFh
Access SFR’s
Bank 15
EFFh
F00h
F7Fh
F80h
FFFh
Advance Information
When a = 0,
the BSR is ignored and this
Access RAM bank is used.
The first 128 bytes are General
Purpose RAM (from Bank 0).
The next 128 bytes are Special
Function Registers (from
Bank 15).
When a = 1,
the BSR is used to specify
the RAM location that the
instruction uses.
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 4-9:
FFFh
FFEh
FFDh
FFCh
FFBh
FFAh
FF9h
FF8h
FF7h
FF6h
FF5h
FF4h
FF3h
FF2h
FF1h
FF0h
FEFh
FEEh
FEDh
FECh
FEBh
FEAh
FE9h
FE8h
FE7h
FE6h
FE5h
FE4h
FE3h
FE2h
FE1h
FE0h
SPECIAL FUNCTION REGISTER MAP
TOSU
TOSH
TOSL
STKPTR
PCLATU
PCLATH
PCL
TBLPTRU
TBLPTRH
TBLPTRL
TABLAT
PRODH
PRODL
INTCON
INTCON2
INTCON3
INDF0
POSTINC0
POSTDEC0
PREINC0
PLUSW0
FSR0H
FSR0L
WREG
INDF1
POSTINC1
POSTDEC1
PREINC1
PLUSW1
FSR1H
FSR1L
BSR
 2001 Microchip Technology Inc.
FDFh
FDEh
FDDh
FDCh
FDBh
FDAh
FD9h
FD8h
FD7h
FD6h
FD5h
FD4h
FD3h
FD2h
FD1h
FD0h
FCFh
FCEh
FCDh
FCCh
FCBh
FCAh
FC9h
FC8h
FC7h
FC6h
FC5h
FC4h
FC3h
FC2h
FC1h
FC0h
INDF2
POSTINC2
POSTDEC2
PREINC2
PLUSW2
FSR2H
FSR2L
STATUS
TMR0H
TMR0L
T0CON
Reserved
OSCCON
LVDCON
WDTCON
RCON
TMR1H
TMR1L
T1CON
TMR2
PR2
T2CON
SSPBUF
SSPADD
SSPSTAT
SSPCON1
SSPCON2
ADRESH
ADRESL
ADCON0
ADCON1
ADCON2
FBFh
FBEh
FBDh
FBCh
FBBh
FBAh
FB9h
FB8h
FB7h
FB6h
FB5h
FB4h
FB3h
FB2h
FB1h
FB0h
FAFh
FAEh
FADh
FACh
FABh
FAAh
FA9h
FA8h
FA7h
FA6h
FA5h
FA4h
FA3h
FA2h
FA1h
FA0h
CCPR1H
CCPR1L
CCP1CON
CCPR2H
CCPR2L
CCP2CON
Reserved
Reserved
Reserved
—
—
—
TMR3H
TMR3L
T3CON
PSPCON
SPBRG
RCREG
TXREG
TXSTA
RCSTA
—
—
—
CSEL2
CSELIO
—
—
—
IPR2
PIR2
PIE2
Advance Information
F9Fh
F9Eh
F9Dh
F9Ch
F9Bh
F9Ah
F99h
F98h
F97h
F96h
F95h
F94h
F93h
F92h
F91h
F90h
F8Fh
F8Eh
F8Dh
F8Ch
F8Bh
F8Ah
F89h
F88h
F87h
F86h
F85h
F84h
F83h
F82h
F81h
F80h
IPR1
PIR1
PIE1
MEMCON
—
TRISJ
TRISH
TRISG
TRISF
TRISE
TRISD
TRISC
TRISB
TRISA
LATJ
LATH
LATG
LATF
LATE
LATD
LATC
LATB
LATA
PORTJ
PORTH
PORTG
PORTF
PORTE
PORTD
PORTC
PORTB
PORTA
DS39541A-page 53
PIC18C601/801
TABLE 4-2:
File Name
REGISTER FILE SUMMARY - PIC18C601/801
Bit 7
Bit 6
Bit 5
—
—
—
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
all other
RESETS(1)
FFFh
TOSU
FFEh
TOSH
Top-of-Stack High Byte (TOS<15:8>)
FFDh
TOSL
Top-of-Stack Low Byte (TOS<7:0>)
FFCh
STKPTR
STKOVF
STKUNF
—
Return Stack Pointer
00-0 0000 00-0 0000
FFBh
PCLATU
—
—
—
Holding Register for PC<20:16>
---0 0000 ---0 0000
FFAh
PCLATH
Holding Register for PC<15:8>
FF9h
PCL
PC Low Byte (PC<7:0>)
FF8h
TBLPTRU
FF7h
TBLPTRH
Program Memory Table Pointer High Byte (TBLPTR<15:8>)
0000 0000 0000 0000
FF6h
TBLPTRL
Program Memory Table Pointer Low Byte (TBLPTR<7:0>)
0000 0000 0000 0000
FF5h
TABLAT
Program Memory Table Latch
0000 0000 0000 0000
FF4h
PRODH
Product Register High Byte
xxxx xxxx uuuu uuuu
FF3h
PRODL
Product Register Low Byte
FF2h
INTCON
FF1h
FF0h
FEFh
INDF0
Uses contents of FSR0 to address data memory - value of FSR0 not changed (not a physical register)
N/A
N/A
FEEh
POSTINC0
Uses contents of FSR0 to address data memory - value of FSR0 post-incremented (not a physical register)
N/A
N/A
FEDh
POSTDEC0
Uses contents of FSR0 to address data memory - value of FSR0 post-decremented
(not a physical register)
N/A
N/A
FECh
PREINC0
Uses contents of FSR0 to address data memory - value of FSR0 pre-incremented
(not a physical register)
N/A
N/A
FEBh
PLUSW0
Uses contents of FSR0 to address data memory -value of FSR0 offset by WREG
(not a physical register)
N/A
N/A
FEAh
FSR0H
FE9h
FSR0L
Indirect Data Memory Address Pointer 0 Low Byte
xxxx xxxx uuuu uuuu
FE8h
WREG
Working Register
xxxx xxxx uuuu uuuu
FE7h
INDF1
Uses contents of FSR1 to address data memory - value of FSR1 not changed (not a physical register)
N/A
N/A
FE6h
POSTINC1
Uses contents of FSR1 to address data memory - value of FSR1 post-incremented
(not a physical register)
N/A
N/A
FE5h
POSTDEC1
Uses contents of FSR1 to address data memory - value of FSR1 post-decremented
(not a physical register)
N/A
N/A
—
Top-of-Stack Upper Byte (TOS<20:16>)
Value on
POR
0000 0000 0000 0000
0000 0000 0000 0000
0000 0000 0000 0000
0000 0000 0000 0000
—
r
Program Memory Table Pointer Upper Byte (TBLPTR<20:16>)
PEIE/GIEL
TMR0IE
INT0E
INTCON2
RBPU
INTEDG0
INTEDG1
INTCON3
INT2P
INT1P
—
—
--r0 0000 --r0 0000
xxxx xxxx uuuu uuuu
GIE/GIEH
—
---0 0000 ---0 0000
—
RBIE
TMR0IF
INTEDG2
—
T0IP
INT2E
INT1E
—
—
INT0F
RBIF
0000 000x 0000 000u
—
RBIP
1111 -1-1 1111 -1-1
INT2F
INT1F
11-0 0-00 11-0 0-00
Indirect Data Memory Address Pointer 0 High
---- xxxx ---- uuuu
FE4h
PREINC1
Uses contents of FSR1 to address data memory - value of FSR1 pre-incremented (not a physical register)
N/A
N/A
FE3h
PLUSW1
Uses contents of FSR1 to address data memory - value of FSR1 offset by WREG (not a physical register)
N/A
N/A
FE2h
FSR1H
FE1h
FSR1L
FE0h
BSR
FDFh
INDF2
Uses contents of FSR2 to address data memory - value of FSR2 not changed (not a physical register)
N/A
N/A
FDEh
POSTINC2
Uses contents of FSR2 to address data memory - value of FSR2 post-incremented (not a physical register)
N/A
N/A
FDDh
POSTDEC2
Uses contents of FSR2 to address data memory - value of FSR2 post-decremented
(not a physical register)
N/A
N/A
FDCh
PREINC2
Uses contents of FSR2 to address data memory - value of FSR2 pre-incremented (not a physical register)
N/A
N/A
FDBh
PLUSW2
Uses contents of FSR2 to address data memory -value of FSR2 offset by WREG (not a physical register)
N/A
N/A
FDAh
FSR2H
FD9h
FSR2L
FD8h
STATUS
Legend
—
—
—
—
Indirect Data Memory Address Pointer 1 High
Indirect Data Memory Address Pointer 1 Low Byte
—
—
—
—
—
—
—
—
xxxx xxxx uuuu uuuu
Bank Select Register
---- 0000 ---- 0000
Indirect Data Memory Address Pointer 2 High
Indirect Data Memory Address Pointer 2 Low Byte
—
—
—
N
---- xxxx ---- uuuu
---- xxxx ---- uuuu
xxxx xxxx uuuu uuuu
OV
Z
DC
C
---x xxxx ---u uuuu
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition, r = reserved
Note 1: Other (non-power-up) RESETS include external RESET through MCLR and Watchdog Timer Reset.
2: These registers can only be modified when the Combination Lock is open.
3: These registers are available on PIC18C801 only.
DS39541A-page 54
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 4-2:
File Name
REGISTER FILE SUMMARY - PIC18C601/801 (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR
Value on
all other
RESETS(1)
FD7h
TMR0H
Timer0 Register High Byte
0000 0000 0000 0000
FD6h
TMR0L
Timer0 Register Low Byte
xxxx xxxx uuuu uuuu
FD5h
T0CON
FD4h
Reserved
TMR0ON
16BIT
T0CS
T0SE
T0PS3
T0PS2
T0PS1
T0PS0
FD3h
OSCCON(2)
—
—
—
—
LOCK
PLLEN
SCS1
SCS0
---- 0000 ---- uuu0
FD2h
LVDCON(2)
—
—
IRVST
LVDEN
LVV3
LVV2
LVV1
LVV0
--00 0101 --00 0101
FD1h
WDTCON(2)
—
—
—
—
WDPS2
WDPS1
WDPS0
FD0h
RCON
IPEN
r
—
RI
TO
PD
POR
FCFh
TMR1H
Timer1 Register High Byte
xxxx xxxx uuuu uuuu
FCEh
TMR1L
Timer1 Register Low Byte
xxxx xxxx uuuu uuuu
1111 1111 1111 1111
rrrr rrrr rrrr rrrr
RD16
T1CKPS1
T1CKPS0 T1OSCEN
T1SYNC
TMR1CS
r
00-1 11qq 00-q qquu
FCDh
T1CON
FCCh
TMR2
Timer2 Register
FCBh
PR2
Timer2 Period Register
FCAh
T2CON
FC9h
SSPBUF
SSP Receive Buffer/Transmit Register
FC8h
SSPADD
SSP Address Register in I2C Slave Mode. SSP Baud Rate Reload Register in I2C Master Mode
FC7h
SSPSTAT
SMP
CKE
D/A
P
S
R/W
UA
BF
0000 0000 0000 0000
FC6h
SSPCON1
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000 0000 0000
FC5h
SSPCON2
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
0000 0000 0000 0000
FC4h
ADRESH
A/D Result Register High Byte
FC3h
ADRESL
A/D Result Register Low Byte
FC2h
ADCON0
FC1h
FC0h
FBFh
CCPR1H
Capture/Compare/PWM Register1 High Byte
xxxx xxxx uuuu uuuu
FBEh
CCPR1L
Capture/Compare/PWM Register1 Low Byte
xxxx xxxx uuuu uuuu
—
—
SWDTEN ---- 0000 ---- xxxx
TMR1ON 0-00 0000 u-uu uuuu
0000 0000 0000 0000
TOUTPS3
1111 1111 1111 1111
TOUTPS2
TOUTPS1
TOUTPS0
TMR2ON
T2CKPS1
T2CKPS0 -000 0000 -000 0000
xxxx xxxx uuuu uuuu
0000 0000 0000 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
—
—
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
--00 0000 --00 0000
ADCON1
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
--00 0000 --00 0000
ADCON2
ADFM
—
—
—
—
ADCS2
ADCS1
ADCS0
0--- -000 0--- -000
FBDh
CCP1CON
FBCh
CCPR2H
Capture/Compare/PWM Register2 High Byte
—
—
FBBh
CCPR2L
Capture/Compare/PWM Register2 Low Byte
FBAh
CCP2CON
FB9h
Reserved
rrrr rrrr rrrr rrrr
FB8h
Reserved
rrrr rrrr rrrr rrrr
FB7h
Reserved
rrrr rrrr rrrr rrrr
—
—
DC1B1
DC2B1
DC1B0
DC2B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
--00 0000 --00 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
CCP2M3
CCP2M2
CCP2M1
CCP2M0
--00 0000 --uu uuuu
FB6h
FB5h
FB4h
FB3h
TMR3H
Timer3 Register High Byte
xxxx xxxx uuuu uuuu
FB2h
TMR3L
Timer3 Register Low Byte
xxxx xxxx uuuu uuuu
FB1h
T3CON
Legend
RD16
T3CCP2
T3CKPS1
T3CKPS0
T3CCP1
T3SYNC
TMR3CS
TMR3ON 0000 0000 uuuu uuuu
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition, r = reserved
Note 1: Other (non-power-up) RESETS include external RESET through MCLR and Watchdog Timer Reset.
2: These registers can only be modified when the Combination Lock is open.
3: These registers are available on PIC18C801 only.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 55
PIC18C601/801
TABLE 4-2:
REGISTER FILE SUMMARY - PIC18C601/801 (CONTINUED)
File Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
—
—
—
—
—
—
CMLK1
CMLK0
Value on
POR
Value on
all other
RESETS(1)
FB0h
PSPCON
FAFh
SPBRG
USART Baud Rate Generator
0000 0000 0000 0000
FAEh
RCREG
USART Receive Register
0000 0000 0000 0000
FADh
TXREG
USART Transmit Register
FACh
TXSTA
CSRC
TX9
TXEN
SYNC
—
BRGH
TRMT
TX9D
0000 -010 0000 -010
FABh
RCSTA
SPEN
RX9
SREN
CREN
ADEN
FERR
OERR
RX9D
0000 000x 0000 000x
CSL7
CSL6
CSL5
CSL4
CSL3
CSL2
CSL1
CSL0
1111 1111 uuuu uuuu
CSIO7
CSIO6
CSIO5
CSIO4
CSIO3
CSIO2
CSIO1
CSIO0
1111 1111 uuuu uuuu
---- --00 ---- --00
0000 0000 0000 0000
FAAh
FA9h
FA8h
FA7h
FA6h
CSEL2(2)
CSELIO
(2)
FA5h
FA4h
FA3h
FA2h
IPR2
—
—
—
—
BCLIP
LVDIP
TMR3IP
CCP2IP
---- 1111 ---- 1111
FA1h
PIR2
—
—
—
—
BCLIF
LVDIF
TMR3IF
CCP2IF
---- 0000 ---- 0000
FA0h
PIE2
—
—
—
—
BCLIE
LVDIE
TMR3IE
CCP2IE
---- 0000 ---- 0000
F9Fh
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-111 1111 -111 1111
F9Eh
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000 -000 0000
F9Dh
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000 -000 0000
F9Ch
MEMCON(2)
EBDIS
PGRM
WAIT1
WAIT0
—
—
WM1
WM0
0000 --00 0000 --00
F9Bh
F9Ah
TRISJ(3)
Data Direction Control Register for PORTJ
1111 1111 1111 1111
F99h
TRISH(3)
Data Direction Control Register for PORTH
1111 1111 1111 1111
F98h
TRISG
F96h
TRISF
Read PORTF Data Latch, Write PORTF Data Latch
1111 1111 1111 1111
F96h
TRISE
Data Direction Control Register for PORTE
1111 1111 1111 1111
F95h
TRISD
Data Direction Control Register for PORTD
1111 1111 1111 1111
F94h
TRISC
Data Direction Control Register for PORTC
1111 1111 1111 1111
F93h
TRISB
Data Direction Control Register for PORTB
1111 1111 1111 1111
F92h
TRISA
F91h
LATJ(3)
Read PORTJ Data Latch, Write PORTJ Data Latch
xxxx xxxx uuuu uuuu
F90h
LATH(3)
Read PORTH Data Latch, Write PORTH Data Latch
xxxx xxxx uuuu uuuu
F8Fh
LATG
—
—
—
—
—
—
—
Read PORTG Data Latch, Write PORTG Data Latch
Data Direction Control Register for PORTA
—
---1 1111 ---1 1111
--11 1111 --11 1111
Read PORTG Data Latch, Write PORTG Data Latch
---x xxxx ---u uuuu
F8Eh
LATF
Read PORTF Data Latch, Write PORTF Data Latch
xxxx xxxx uuuu uuuu
F8Dh
LATE
Read PORTE Data Latch, Write PORTE Data Latch
xxxx xxxx uuuu uuuu
F8Ch
LATD
Read PORTD Data Latch, Write PORTD Data Latch
xxxx xxxx uuuu uuuu
F8Bh
LATC
Read PORTC Data Latch, Write PORTC Data Latch
xxxx xxxx uuuu uuuu
F8Ah
LATB
Read PORTB Data Latch, Write PORTB Data Latch
xxxx xxxx uuuu uuuu
F89h
LATA
F88h
PORTJ(3)
Read PORTJ Pins, Write PORTJ Data Latch
xxxx xxxx uuuu uuuu
F87h
PORTH(3)
Read PORTH pins, Write PORTH Data Latch
xxxx xxxx uuuu uuuu
F86h
PORTG
F85h
PORTF
Legend
—
—
—
—
Read PORTA Data Latch, Write PORTA Data Latch
—
Read PORTG pins, Write PORTG Data Latch
Read PORTF pins, Write PORTF Data Latch
--xx xxxx --uu uuuu
---x xxxx ---u uuuu
xxxx xx00 uuuu uu00
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition, r = reserved
Note 1: Other (non-power-up) RESETS include external RESET through MCLR and Watchdog Timer Reset.
2: These registers can only be modified when the Combination Lock is open.
3: These registers are available on PIC18C801 only.
DS39541A-page 56
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 4-2:
File Name
REGISTER FILE SUMMARY - PIC18C601/801 (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR
Value on
all other
RESETS(1)
F84h
PORTE
Read PORTE Pins, Write PORTE Data Latch
xxxx xxxx uuuu uuuu
F83h
PORTD
Read PORTD pins, Write PORTD Data Latch
xxxx xxxx uuuu uuuu
F82h
PORTC
Read PORTC pins, Write PORTC Data Latch
xxxx xxxx uuuu uuuu
F81h
PORTB
Read PORTB pins, Write PORTB Data Latch
xxxx xxxx uuuu uuuu
F80h
PORTA
Legend
—
—
Read PORTA pins, Write PORTA Data Latch
--0x 0000 --0u 0000
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition, r = reserved
Note 1: Other (non-power-up) RESETS include external RESET through MCLR and Watchdog Timer Reset.
2: These registers can only be modified when the Combination Lock is open.
3: These registers are available on PIC18C801 only.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 57
PIC18C601/801
4.10
Access Bank
4.11
Bank Select Register (BSR)
The Access Bank is an architectural enhancement that
is very useful for C compiler code optimization. The
techniques used by the C compiler are also useful for
programs written in assembly.
The need for a large general purpose memory space
dictates a RAM banking scheme. When using direct
addressing, the BSR should be configured for the
desired bank.
This data memory region can be used for:
BSR<3:0> holds the upper 4 bits of the 12-bit RAM
address. The BSR<7:4> bits will always read ’0’s, and
writes will have no effect.
•
•
•
•
•
Intermediate computational values
Local variables of subroutines
Faster context saving/switching of variables
Common variables
Faster evaluation/control of SFR’s (no banking)
A MOVLB instruction has been provided in the instruction set to assist in selecting banks.
If the currently selected bank is not implemented, any
read will return all '0's and all writes are ignored. The
STATUS register bits will be set/cleared as appropriate
for the instruction performed.
The Access Bank is comprised of the upper 128 bytes
in Bank 15 (SFR’s) and the lower 128 bytes in Bank 0.
These two sections will be referred to as Access Bank
High and Access Bank Low, respectively. Figure 4-8
indicates the Access Bank areas.
Each Bank extends up to 0FFh (256 bytes). All data
memory is implemented as static RAM.
A bit in the instruction word specifies if the operation is
to occur in the bank specified by the BSR register, or in
the Access Bank.
A MOVFF instruction ignores the BSR, since the 12-bit
addresses are embedded into the instruction word.
Section 4.12 provides a description of indirect addressing, which allows linear addressing of the entire RAM
space.
When forced in the Access Bank (a = ’0’), the last
address in Access Bank Low is followed by the first
address in Access Bank High. Access Bank High maps
all Special Function Registers so that these registers
can be accessed without any software overhead.
FIGURE 4-10:
DIRECT ADDRESSING
Direct Addressing
BSR<3:0>
bank select(2)
7
from opcode(3)
0
location select(3)
00h
01h
0Eh
0Fh
000h
100h
E00h
F00h
0FFh
1FFh
EFFh
FFFh
Bank 14
Bank 15
Data
Memory(1)
Bank 0
Bank 1
Note 1: For register file map detail, see Table 4-2.
2: The access bit of the instruction can be used to force an override of the selected bank (BSR<3:0>) to the
registers of the Access Bank.
3: The MOVFF instruction embeds the entire 12-bit address in the instruction.
DS39541A-page 58
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
4.12
Indirect Addressing, INDF and
FSR Registers
Indirect addressing is a mode of addressing data memory, where the data memory address in the instruction
is not fixed. A SFR register is used as a pointer to the
data memory location that is to be read or written. Since
this pointer is in RAM, the contents can be modified by
the program. This can be useful for data tables in the
data memory and for software stacks. Figure 4-11
shows the operation of indirect addressing. This shows
the moving of the value to the data memory address
specified by the value of the FSR register.
Indirect addressing is possible by using one of the
INDFn (0 ≤ n ≤ 2) registers. Any instruction using the
INDFn register actually accesses the register indicated
by the File Select Register, FSRn (0 ≤ n ≤ 2). Reading
the INDFn register itself indirectly (FSRn = ’0’), will read
00h. Writing to the INDFn register indirectly, results in a
no-operation. The FSRn register contains a 12-bit
address, which is shown in Figure 4-11.
Example 4-6 shows a simple use of indirect addressing
to clear the RAM in Bank 1 (locations 100h-1FFh) in a
minimum number of instructions.
EXAMPLE 4-6:
LFSR
NEXTCLRF
HOW TO CLEAR RAM
(BANK 1) USING
INDIRECT ADDRESSING
FSR0, 100h
POSTINC0
BTFSS FSR0H, 1
BRA
NEXT
CONTINUE;
:
;
;
;
;
;
;
;
Clear INDF
register
& inc pointer
All done
with Bank1?
NO, clear next
; YES, continue
There are three indirect addressing registers. To
address the entire data memory space (4096 bytes),
these registers are 12-bit wide. To store the 12-bits of
addressing information, two 8-bit registers are
required. These indirect addressing registers are:
1.
2.
3.
FSR0: composed of FSR0H:FSR0L
FSR1: composed of FSR1H:FSR1L
FSR2: composed of FSR2H:FSR2L
In addition, there are registers INDF0, INDF1 and
INDF2, which are not physically implemented. Reading
or writing to these registers activates indirect addressing, with the value in the corresponding FSR register
being the address of the data.
If INDF0, INDF1, or INDF2 are read indirectly via an
FSR, all ’0’s are read (zero bit is set). Similarly, if
INDF0, INDF1, or INDF2 are written to indirectly, the
operation will be equivalent to a NOP instruction and the
STATUS bits are not affected.
4.12.1
INDIRECT ADDRESSING
OPERATION
Each FSR register has an INDF register associated
with it, plus four additional register addresses. Performing an operation on one of these five registers determines how the FSR will be modified during indirect
addressing.
When data access is done to one of the five INDFn
locations, the address selected will configure the FSRn
register to:
• Do nothing to FSRn after an indirect access (no
change) - INDFn
• Auto-decrement FSRn after an indirect access
(post-decrement) - POSTDECn
• Auto-increment FSRn after an indirect access
(post-increment) - POSTINCn
• Auto-increment FSRn before an indirect access
(pre-increment) - PREINCn
• Use the value in the WREG register as an offset
to FSRn. Do not modify the value of the WREG or
the FSRn register after an indirect access (no
change) - PLUSWn
When using the auto-increment or auto-decrement features, the effect on the FSR is not reflected in the
STATUS register. For example, if the indirect address
causes the FSR to equal '0', the Z bit will not be set.
Incrementing or decrementing an FSR affects all 12
bits. That is, when FSRnL overflows from an increment,
FSRnH will be incremented automatically.
Adding these features allows the FSRn to be used as a
software stack pointer, in addition to its uses for table
operations in data memory.
Each FSR has an address associated with it that performs an indexed indirect access. When a data access
to this INDFn location (PLUSWn) occurs, the FSRn is
configured to add the 2’s complement value in the
WREG register and the value in FSR to form the
address before an indirect access. The FSR value is
not changed.
If an indirect addressing operation is done where the
target address is an FSRnH or FSRnL register, the
write operation will dominate over the pre- or postincrement/decrement functions.
If an instruction writes a value to INDF0, the value will
be written to the address indicated by FSR0H:FSR0L.
A read from INDF1 reads the data from the address
indicated by FSR1H:FSR1L. INDFn can be used in
code anywhere an operand can be used.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 59
PIC18C601/801
FIGURE 4-11:
INDIRECT ADDRESSING
Indirect Addressing
11
FSR Register
7
8
FSRnH
0
FSRnL
Location Select
0000h
Data
Memory(1)
0FFFh
Note 1: For register file map detail, see Table 4-2.
DS39541A-page 60
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
4.13
STATUS Register
The STATUS register, shown in Register 4-3, contains
the arithmetic status of the ALU. The STATUS register
can be the destination for any instruction, as with any
other register. If the STATUS register is the destination
for an instruction that affects the Z, DC, C, OV, or N bits,
then the write to these five bits is disabled. These bits
are set or cleared according to the device logic. Therefore, the result of an instruction with the STATUS register as destination may be different than intended.
REGISTER 4-3:
For example, CLRF STATUS will clear all implemented
bits and set the Z bit. This leaves the STATUS register
as ---0 0100 (where - = unimplemented).
It is recommended, therefore, that only BCF, BSF,
SWAPF, MOVFF and MOVWF instructions are used to
alter the STATUS register, because these instructions
do not affect the Z, C, DC, OV, or N bits from the
STATUS register. For other instructions which do not
affect the status bits, see Table 20-2.
Note:
The C and DC bits operate as a borrow and
digit borrow bit respectively, in subtraction.
STATUS REGISTER
U-0
U-0
U-0
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
—
—
—
N
OV
Z
DC
C
bit 7
bit 0
bit 7-5
Unimplemented: Read as '0'
bit 4
N: Negative bit
This bit is used for signed arithmetic (2’s complement). It indicates whether the result of the ALU
operation was negative (ALU MSb = 1).
1 = Result was negative
0 = Result was positive
bit 3
OV: Overflow bit
This bit is used for signed arithmetic (2’s complement). It indicates an overflow of the 7-bit
magnitude, which causes the sign bit (bit 7) to change state.
1 = Overflow occurred for signed arithmetic (in this arithmetic operation)
0 = No overflow occurred
bit 2
Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero
bit 1
DC: Digit carry/borrow bit
For arithmetic addition and subtraction instructions
1 = A carry-out from the 4th low order bit of the result occurred
0 = No carry-out from the 4th low order bit of the result
Note:
bit 0
For borrow, the polarity is reversed. A subtraction is executed by adding the two’s
complement of the second operand. For rotate (RRCF, RRNCF, RLCF, and
RLNCF) instructions, this bit is loaded with either the bit 4, or bit 3 of the source
register.
C: Carry/borrow bit
For arithmetic addition and subtraction instructions
1 = A carry-out from the most significant bit of the result occurred
0 = No carry-out from the most significant bit of the result occurred
Note:
For borrow, the polarity is reversed. A subtraction is executed by adding the two’s
complement of the second operand. For rotate (RRCF, RLCF) instructions, this bit
is loaded with either the high, or low order bit of the source register.
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 61
PIC18C601/801
4.14
RCON Register
Note:
The Reset Control (RCON) register contains flag bits
that allow differentiation between the sources of a
device RESET. These flags include the TO, PD, POR
and RI bits. This register is readable and writable.
REGISTER 4-4:
It is recommended that the POR bit be set
after a Power-on Reset has been detected,
so that subsequent Power-on Resets may
be detected.
RCON REGISTER
R/W-0
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-0
U-0
IPEN
r
—
RI
TO
PD
POR
r
bit 7
bit 0
bit 7
IPEN: Interrupt Priority Enable bit
1 = Enable priority levels on interrupts
0 = Disable priority levels on interrupts (16CXXX compatibility mode)
bit 6
Reserved: Maintain as ‘0’
bit 5
Unimplemented: Read as '0'
bit 4
RI: RESET Instruction Flag bit
1 = The RESET instruction was not executed
0 = The RESET instruction was executed causing a device RESET
(must be set in software after RESET instruction was executed)
bit 3
TO: Watchdog Time-out Flag bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction
0 = A WDT time-out occurred
bit 2
PD: Power-down Detection Flag bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction
bit 1
POR: Power-on Reset Status bit
1 = A Power-on Reset has not occurred
0 = A Power-on Reset occurred
(must be set in software after a Power-on Reset occurs)
bit 0
Reserved: Maintain as ‘0’
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
r
DS39541A-page 62
x = Bit is unknown
= Reserved
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
5.0
EXTERNAL MEMORY
INTERFACE
The External Memory Interface is a feature of the
PIC18C601/801 that allows the processor to access
external memory devices, such as FLASH, EPROM,
SRAM, etc. Memory mapped peripherals may also be
accessed.
The External Memory Interface physical implementation includes up to 26 pins on the PIC18C601 and up to
38 pins on the PIC18C801. These pins are reserved for
external address/data bus functions.
REGISTER 5-1:
These pins are multiplexed with I/O port pins, but the
I/O functions are only enabled when program execution
takes place in internal Boot RAM and the EBDIS bit in
the MEMCON register is set (see Register 5-1).
5.1
Memory Control Register
(MEMCON)
Register 5-1 shows the Memory Control Register
(MEMCON). This register contains bits used to control
the operation of the External Memory Interface.
MEMCON REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
U-0
U-0
R/W-0
R/W-0
EBDIS
PGRM
WAIT1
WAIT0
—
—
WM1
WM0
bit7
bit0
bit 7
EBDIS: External Bus Disable
1 = External system bus disabled, all external bus drivers are mapped as I/O ports
0 = External system bus enabled, and I/O ports are disabled
bit 6
PGRM: Program RAM Enable
1 = 512 bytes of internal RAM enabled as internal program memory from location 1FFE00h to
1FFFFFh, external program memory at these locations is unused. Internal GPR memory
from 400h to 5FFh is disabled and returns 00h.
0 = Internal RAM enabled as internal GPR memory from 400h to 5FFh. Program memory from
location 1FFE00h to 1FFFFFh is configured as external program memory.
bit 5-4
WAIT<1:0>: Table Reads and Writes Bus Cycle Wait Count
11 = Table reads and writes will wait 0 TCY
10 = Table reads and writes will wait 1 TCY
01 = Table reads and writes will wait 2 TCY
00 = Table reads and writes will wait 3 TCY
bit 3-2
Unimplemented: Read as '0'
bit 1-0
WM<1:0>: TABLWT Operation with 16-bit Bus
1X = Word Write mode: TABLAT0 and TABLAT1 word output, WRH active when TABLAT1 written
01 = Byte Select mode: TABLAT data copied on both MS and LS Byte, WRH and (UB or LB) will
activate
00 = Byte Write mode: TABLAT data copied on both MS and LS Byte, WRH or WRL will activate
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 63
PIC18C601/801
5.2
8-bit Mode
Therefore, the designer must choose external memory
devices according to timing calculations based on 1/2
Tcy (2 times instruction rate). For proper memory
speed selection, glue logic propagation delay times
must be considered along with setup and hold times.
The External Memory Interface can operate in 8-bit
mode. The mode selection is not software configurable,
but is programmable via the configuration bits.
There are two types of connections in 8-bit mode. They
are referred to as:
The Address Latch Enable (ALE) pin indicates that the
address bits A<7:0> are available on the External
Memory Interface bus. The OE output enable signal will
enable one byte of program memory for a portion of the
instruction cycle, then BA0 will change and the second
byte will be enabled to form the 16-bit instruction word.
The least significant bit of the address, BA0, must be
connected to the memory devices in this mode.
Figure 5-1 shows an example of 8-bit Multiplexed
mode on the PIC18C601. The control signals used in
8-bit Multiplexed mode are outlined in Table 5-1.
Register 5-2 describes 8-bit Multiplexed mode timing.
• 8-bit Multiplexed
• 8-bit De-Multiplexed
5.2.1
8-BIT MULTIPLEXED MODE
The 8-bit Multiplexed mode applies only to the
PIC18C601. Data and address lines are multiplexed on
port pins and must be decoded with glue logic.
For 8-bit Multiplexed mode on the PIC18C601, the
instructions will be fetched as two 8-bit bytes on a
shared data/address bus (PORTD). The two bytes are
sequentially fetched within one instruction cycle (TCY).
FIGURE 5-1:
8-BIT MULTIPLEXED MODE EXAMPLE
D<7:0>
A<17:0>
AD<7:0>
A<x:1>
373
A0
ALE
D<7:0>
PIC18C601
CE
OE WR(2)
BA0
A16, AD<15:8>
CS1
OE
WRL
Note 1: This signal only applies to Table Writes. See Section 6.0, Table Reads and Writes.
TABLE 5-1:
8-BIT MULTIPLEXED MODE CONTROL SIGNALS
Name
8-bit Mux
Mode
RG0/ALE
ALE
Address Latch Enable (ALE) control pin
RG1/OE
OE
Output Enable (OE) control pin
RG2/WRL
WRL
Write Low (WRL) control pin
RG4/BA0
BA0
Byte address bit 0
RF3/CSIO
CSIO
Chip Select I/O (See Section 5.4)
RF5/CS1
CS1
Chip Select 1 (See Section 5.4)
DS39541A-page 64
Function
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 5-2:
8-BIT MULTIPLEXED MODE TIMING
Q1
Q4
03Ah
A16, AD<15:8>
AD<7:0>
Q3
Q2
ABh
55h
0Eh
BA0
ALE
OE
Opcode Fetch
MOVLW 55h
from 007556h
5.2.2
8-BIT DE-MULTIPLEXED MODE
The 8-bit De-Multiplexed mode applies only to the
PIC18C801. Data and address lines are available separately. External components are not necessary in this
mode.
For 8-bit De-Multiplexed mode on the PIC18C801, the
instructions are fetched as two 8-bit bytes on a dedicated data bus (PORTJ). The address will be presented for the entire duration of the fetch cycle on a
separate address bus. The two instruction bytes are
sequentially fetched within one instruction cycle (TCY).
Therefore, the designer must choose external memory
devices according to timing calculations, based on 1/2
TCY (2 times instruction rate). For proper memory speed
selection, setup and hold times must be considered.
 2001 Microchip Technology Inc.
The Address Latch Enable (ALE) pin is left unconnected, since glue logic is not necessary. The OE output enable signal will enable one byte of program
memory for a portion of the instruction cycle, then BA0
will change and the second byte will be enabled to form
the 16-bit instruction word. The least significant bit of
the address, BA0, must be connected to the memory
devices in this mode. Figure 5-3 shows an example of
8-bit De-Multiplexed mode on the PIC18C801. The
control signals used in 8-bit De-Multiplexed mode are
outlined in Register 5-2. Register 5-4 describes 8-bit
De-Multiplexed mode timing.
Advance Information
DS39541A-page 65
PIC18C601/801
FIGURE 5-3:
8-BIT DE-MULTIPLEXED MODE EXAMPLE
BA0
A0
A<20:0>
A<x:1>
A<19:16>, AD<15:0>
D<7:0>
D<7:0>
D<7:0>
PIC18C801
CE
OE WR(1)
ALE
CS1
OE
WRL
Note 1: This signal only applies to Table Writes. See Section 6.0, Table Reads and Writes.
TABLE 5-2:
8-BIT DE-MULTIPLEXED MODE CONTROL SIGNALS
Name
8-bit De-Mux Mode
RG0/ALE
ALE
RG1/OE
OE
RG2/WRL
WRL
Function
Address Latch Enable (ALE) control pin
Output Enable (OE) control pin
Write Low (WRL) control pin
RG4/BA0
BA0
Byte address bit 0
RF3/CSIO
CSIO
Chip Select I/O (See Section 5.4)
RF4/CS2
CS2
Chip Select 2 (See Section 5.4)
RF5/CS1
CS1
Chip Select 1 (See Section 5.4)
FIGURE 5-4:
8-BIT DE-MULTIPLEXED MODE TIMING
Q1
A16, AD<15:8>
Q3
Q2
Q4
03Ah
55h
AD<7:0>
0Eh
BA0
ALE
OE
Opcode Fetch
MOVLW 55h
from 007556h
DS39541A-page 66
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
5.3
16-bit Mode
The External Memory Interface can operate in 16-bit
mode. The mode selection is not software configurable,
but is programmable via the configuration bits.
The WM<1:0> bits in the MEMCON register determine
three types of connections in 16-bit mode. They are
referred to as:
• 16-bit Byte Write
• 16-bit Word Write
• 16-bit Byte Select
These three different configurations allow the designer
maximum flexibility in using 8-bit and 16-bit memory
devices.
FIGURE 5-5:
For all 16-bit modes, the Address Latch Enable (ALE)
pin indicates that the address bits A<15:0> are available on the External Memory Interface bus. Following
the address latch, the output enable signal (OE ) will
enable both bytes of program memory at once to form
a 16-bit instruction word.
In Byte Select mode, JEDEC standard FLASH memories will require BA0 for the byte address line, and one
I/O line, to select between byte and word mode. The
other 16-bit modes do not need BA0. JEDEC standard
static RAM memories will use the UB or UL signals for
byte selection.
5.3.1
16-BIT BYTE WRITE MODE
Figure 5-5 shows an example of 16-bit Byte Write
mode for the PIC18C601/801.
16-BIT BYTE WRITE MODE EXAMPLE
D<7:0>
(MSB)
PIC18C801
AD<15:8>
373
A<19:0>
D<15:8>
373
A<x:0>
A<x:0>
D<7:0>
CE
AD<7:0>
(LSB)
OE
D<7:0>
D<7:0>
CE
WR(1)
OE
WR(1)
ALE
A<19:16>
CS1
OE
WRH
WRL
Note 1: This signal only applies to Table Writes. See Section 6.0, Table Reads and Writes.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 67
PIC18C601/801
5.3.2
16-BIT WORD WRITE MODE
Figure 5-6 shows an example of 16-bit Word Write
mode for the PIC18C801.
FIGURE 5-6:
16-BIT WORD WRITE MODE EXAMPLE
PIC18C801
373
AD<7:0>
A<20:1>
JEDEC Word
EPROM Memory
A<x:0>
D<15:0>
D<15:0>
CE
AD<15:8>
OE
WR(1)
373
ALE
A<19:16>
CS1
OE
WRH
Note 1: This signal only applies to Table Writes. See Section 6.0, Table Reads and Writes.
5.3.3
16-BIT BYTE SELECT MODE
Figure 5-7 shows an example of 16-bit Byte Select
mode for the PIC18C801.
FIGURE 5-7:
16-BIT BYTE SELECT MODE EXAMPLE
PIC18C801
AD<7:0>
373
A<20:1>
A<x:1>
JEDEC Word
FLASH Memory
D<15:0>
D<15:0>
CE
AD<15:8>
373
A0
ALE
BYTE/WORD
OE WR(1)
A<19:16>
OE
WRH
WRL
BA0
A<20:1>
A<x:1>
JEDEC Word
SRAM Memory
I/O
CS1
CS2
D<15:0>
D<15:0>
CE
LB
LB
UB
UB
OE
WR(1)
Note 1: This signal only applies to Table Writes. See Section 6.0, Table Reads and Writes.
DS39541A-page 68
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
5.3.4
16-BIT MODE CONTROL SIGNALS
Table 5-3 describes the 16-bit mode control signals for
the PIC18C601/801.
TABLE 5-3:
PIC18C601/801 16-BIT MODE CONTROL SIGNALS
Name
18C601 16-bit
Mode
18C801 16-bit
Mode
RG0/ALE
RG1/OE
RG2/WRL
RG3/WRH
RG4/BA0
RF3/CSIO
RF4/CS2
RF5/CS1
RF6/UB
RF7/LB
I/O
ALE
OE
WRL
WRH
BA0
CSIO
N/A
CS1
UB
LB
I/O
ALE
OE
WRL
WRH
BA0
CSIO
CS2
CS1
UB
LB
I/O
5.3.5
Function
Address Latch Enable (ALE) control pin
Output Enable (OE) control pin
Write Low (WRL) control pin
Write High (WRH) control pin
Byte address bit 0
Chip Select I/O (See Section 5.4)
Chip Select 2 (See Section 5.4)
Chip Select 1 (See Section 5.4)
Upper Byte Enable (UB) control pin
Lower Byte Enable (LB) control pin
I/O as BYTE/WORD control pin for JEDEC FLASH
16-BIT MODE TIMING
Figure 5-8 describes the 16-bit mode timing for the
PIC18C601/801.
FIGURE 5-8:
16-BIT MODE TIMING
Q1
Q2
Q4
Q3
03Ah
A16, AD<15:8>
3AABh
AD<7:0>
0E55h
BA0
ALE
OE
WRH
‘1’
WRL
‘1’
Opcode Fetch
MOVLW 55h
from 007556h
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 69
PIC18C601/801
5.4
Chip Selects
Chip select signals are used to select regions of external memory and I/O devices for access. The
PIC18C801 has three chip selects and all are programmable. The chip select signals are CS1, CS2 and
CSIO. CS1 and CS2 are general purpose chip selects
that are used to enable large portions of program memory. CSIO is used to enable external I/O expansion.
The PIC18C601uses two of these programmable chip
selects: CS1 and CSIO.
REGISTER 5-2:
Two SFRs are used to control the chip select signals.
These are CSEL2 and CSELIO (see Register 5-2 and
Register 5-3). A chip select signal is asserted low when
the CPU makes an access to a dedicated range of
addresses specified in the chip select registers, CSEL2
and CSELIO. The 8-bit value found in either of these
registers is decoded as one of 256, 8K banks of program memory. If both chip select registers are 00h, all
of the chip select signals are disabled and their corresponding pins are configured as I/O. Since the last 512
bytes of program memory are dedicated to internal program RAM, the chip select signals will not activate if the
program memory address falls in this range.
CSEL2 REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
CSL7
CSL6
CSL5
CSL4
CSL3
CSL2
CSL1
CSL0
bit 7
bit 7-0
bit 0
CSL<7:0>: Chip Select 2 Address Decode bits
XXh = All eight bits are compared to the Most Significant bits PC<20:13> of the program
counter. If PC<20:13> ≥ CSL<7:0> register, then the CS2 signal is low.
If PC<20:13> < CSL<7:0>, CS2 is high.
00h = CS2 is inactive
Legend:
REGISTER 5-3:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
x = Bit is unknown
CSELIO REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
CSIO7
CSIO6
CSIO5
CSIO4
CSIO3
CSIO2
CSIO1
CSIO0
bit7
bit 7-0
bit0
CSIO<7:0>: Chip Select IO Address Decode bits
XXh = All eight bits are compared to the Most Significant bits PC<20:13> of the program
counter. If PC<20:13> = CSIO<7:0>, then the CSIO signal is low. If not, CSIO is high.
00h = CSIO is inactive
Legend:
DS39541A-page 70
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
5.4.1
CHIP SELECT 1 (CS1)
CS1 is enabled by writing a value other than 00h into
either the CSEL2 register, or the CSELIO register. If
both of the chip select registers are programmed to
00h, the CS1 signal is not enabled and the RF5 pin is
configured as I/O.
CS1 is low for all addresses in which CS2 and CSELIO
are high. Therefore, if CSEL2 = 20h and CSELIO = 80h,
then the CS1 signal will be low for the address that falls
between 000000h and (2000h x 20h) - 1 = 03FFFFh.
CS1 will always be low for the lower 8K of program
memory. Figure 5-9 shows an example address map for
CS1.
5.4.2
CHIP SELECT 2 (CS2)
CS2 is enabled for program memory accesses, starting
at the address derived by the 8-bit value contained in
CSEL2. For example, if the value contained in the
CSEL2 register is 80h, then the CS2 signal will be
asserted low whenever the address is greater than or
equal to 2000h x 80h = 100000h.
FIGURE 5-9:
A 00h value in the CSEL2 register will disable the CS2
signal and will configure the RF4 pin as I/O. Figure 5-9
shows an example address map for CS2.
5.4.3
CHIP SELECT I/O (CSIO)
CSIO is enabled for a fixed 8K address range starting
at the address defined by the 8-bit value contained in
CSELIO. If, for instance, the value contained in the
CSELIO register is 80h, then the CSIO signal will be
low for the address range between 100000h and
101FFFh.
If the 8K address block overlaps the address range
specified in the CSEL2 register, the CSIO signal will be
low, and the CS2 signal will be high, for that region.
A 00h value in the CSELIO register will disable the
CSIO signal and will configure the RF3 pin as I/O.
Figure 5-9 shows an example address map for CSIO.
EXAMPLE CONFIGURATION ADDRESS MAP FOR CS1, CS2, AND CSIO
CSEL2 = FFh (DEFAULT)
CSELIO = FFh (DEFAULT)
PROGRAM MEMORY
CSEL2 = 80h
CSELIO = 00h
CSEL2 = 20h
CSELIO = 80h
PROGRAM MEMORY
000000h
PROGRAM MEMORY
000000h
000000h
03FFFFh
040000h
0FFFFFh
100000h
0FFFFFh
100000h
101FFFh
102000h
1FFDFFh
1FFE00h
1FFFFFh
= CS1 ACTIVE
 2001 Microchip Technology Inc.
1FFDFFh
1FFE00h
1FFFFFh
= CS2 ACTIVE
= CSIO ACTIVE
Advance Information
1FFDFFh
1FFE00h
1FFFFFh
= NO CHIP SELECT ACTIVE
INTERNAL EXECUTION IF
PGRM = 1
DS39541A-page 71
PIC18C601/801
5.5
External Wait Cycles
The external memory interface supports wait cycles.
Wait cycles only apply to Table Read and Table Write
operations over the external bus. See Section 6.0 for
more details.
Since the device execution is tied to instruction fetches,
there is no need to execute faster than the fetch rate.
So, if the program needs to be slowed, the processor
speed must be slowed with a different TCY time.
DS39541A-page 72
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
6.0
TABLE READS/TABLE WRITES
Table Read operations retrieve data from external program memory and place it into the data memory space.
Figure 6-1 shows the operation of a Table Read with
program and data memory.
PIC18C601/801 devices use two memory spaces: the
external program memory space and the data memory
space. Table Reads and Table Writes have been provided to move data between these two memory spaces
through an 8-bit register (TABLAT).
Table Write operations store data from the data memory space into external program memory. Figure 6-2
shows the operation of a Table Write with external program and data memory.
The operations that allow the processor to move data
between the data and external program memory
spaces are:
Table operations work with byte entities. A table block
containing data is not required to be word aligned, so a
table block can start and end at any byte address. If a
Table Write is being used to write an executable program to program memory, program instructions must
be word aligned.
• Table Read (TBLRD)
• Table Write (TBLWT)
FIGURE 6-1:
TABLE READ OPERATION
Table Latch (8-bit)
Table Pointer(1)
TBLPTRU
TBLPTRH
TABLAT
TBLPTRL
External Program Memory
Program Memory
(TBLPTR)
Instruction: TBLRD*
Note 1: Table Pointer points to a byte in external program memory.
FIGURE 6-2:
TABLE WRITE OPERATION
Table Pointer(1)
TBLPTRU
TBLPTRH
Table Latch (8-bit)
TABLAT
TBLPTRL
External Program Memory
Instruction: TBLWT*
External
Program Memory
(TBLPTR)
Note 1: Table Pointer points to a byte in external program memory.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 73
PIC18C601/801
6.1
6.1.2
Control Registers
Several control registers are used in conjunction with
the TBLRD and TBLWT instructions. These include:
• TABLAT register
• TBLPTR registers
6.1.1
TABLAT - TABLE LATCH REGISTER
The Table Latch (TABLAT) is an 8-bit register mapped
into the SFR space. The Table Latch is used to hold
8-bit data during data transfers between program memory and data memory.
TABLE 6-1:
The Table Pointer (TBLPTR) addresses a byte within
the program memory. The TBLPTR is comprised of
three SFR registers (Table Pointer Upper byte, High
byte and Low byte). These three registers
(TBLPTRU:TBLPTRH:TBLPTRL) join to form a 21-bit
wide pointer. The 21-bits allow the device to address up
to 2 Mbytes of program memory space.
The table pointer TBLPTR is used by the TBLRD and
TBLWRT instructions. These instructions can update
the TBLPTR in one of four ways, based on the table
operation. These operations are shown in Table 6-1.
These operations on the TBLPTR only affect the low
order 21-bits.
TABLE POINTER OPERATIONS WITH TBLRD AND TBLWT INSTRUCTIONS
Example
TBLRD*
TBLWT*
Operation on Table Pointer
TBLPTR is not modified
TBLRD*+
TBLWT*+
TBLPTR is incremented after the read/write
TBLRD*TBLWT*-
TBLPTR is decremented after the read/write
TBLRD+*
TBLWT+*
TBLPTR is incremented before the read/write
DS39541A-page 74
TBLPTR - TABLE POINTER
REGISTER
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
6.2
Table Read
Table Reads from external program memory are
performed one byte at a time. If the external interface is
8-bit, the bus interface circuitry in TABLAT will load the
external value into TABLAT. If the external interface is
16-bit, interface circuitry in TABLAT will select either the
high or low byte of the data from the 16-bit bus, based
on the least significant bit of the address.
The TBLRD instruction is used to retrieve data from
external program memory and place it into data
memory.
TBLPTR points to a byte address in external program
memory space. Executing TBLRD places the byte into
TABLAT. In addition, TBLPTR can be modified automatically for the next Table Read operation.
EXAMPLE 6-1:
; Read
CLRF
CLRF
MOVLW
MOVWF
TBLRD*
Example 6-1describes how to use TBLRD. Figure 6-3
and Figure 6-4 show Table Read timings for an 8-bit
external interface, and Figure 6-5 describes Table
Read timing for a 16-bit interface.
TABLE READ CODE EXAMPLE
a byte from location 0020h
TBLPTRU
; clear upper 5 bits of TBLPTR
TBLPTRH
; clear higher 8 bits of TBLPTR
20h
; Load 20h into
TBLPTRL
; TBLPTRL
; Data is in TABLAT
TBLRD EXTERNAL INTERFACE TIMING (8-BIT MULTIPLEXED MODE)
FIGURE 6-3:
Q1
Q2
A<15:8>
AD<7:0>
Q3
Q4
Q1
Q2
03Ah
AAh
08h
Q3
Q4
Q1
Q2
03Ah
00h
ABh
55h
Q3
Q4
Q1
Q2
CCFh
0Eh
33h
Q3
Q4
03Ah
92h
ACh
55h
0Fh
BA0
ALE
OE
’1’
WRH ’1’
’1’
WRL ’1’
Memory
Cycle
Instruction
Execution
Opcode Fetch
TBLRD*
from 007554h
Opcode Fetch
MOVLW 55h
from 007556h
TABLRD 92h
from 199E67h
INST(PC-2)
TBLRD Cycle1
TBLRD Cycle2
 2001 Microchip Technology Inc.
Advance Information
Opcode Fetch
ADDLW 55h
from 007558h
MOVLW
DS39541A-page 75
PIC18C601/801
FIGURE 6-4:
TBLRD EXTERNAL INTERFACE TIMING (8-BIT DE-MULTIPLEXED MODE)
Q1
Q2
Q3
A<15:8>
03AAAh
AD<7:0>
08h
Q4
Q1
Q2
Q3
Q4
Q1
03AABh
00h
55h
Q2
Q3
Q4
Q1
CCF33h
0Eh
Q2
Q3
Q4
03AACh
55h
92h
BA0
ALE
OE
’1’
’1’
’1’
’1’
WRH
WRL
Memory
Cycle
Instruction
Execution
Opcode Fetch
TBLRD*
from 007554h
Opcode Fetch
MOVLW 55h
from 007556h
TABLRD 92h
from 199E67h
INST(PC-2)
TBLRD Cycle1
TBLRD Cycle2
MOVLW
TBLRD EXTERNAL BUS TIMING (16-BIT MODE)
FIGURE 6-5:
Q1
Q2
A<19:16>
Q3
Q4
Q1
Q2
3AAAh
Q3
Q4
Q1
Q2
0h
0h
AD<15:0>
Opcode Fetch
ADDLW 55h
from 007558h
0008h
3AABh
Q3
Q4
Q1
Q2
Ch
0E55h
CF33h
Q3
Q4
0h
9256h
3AACh
0F55h
BA0
ALE
OE
’1’
’1’
’1’
’1’
WRH
WRL
Memory
Cycle
Instruction
Execution
DS39541A-page 76
Opcode Fetch
TBLRD*
from 007554h
Opcode Fetch
MOVLW 55h
from 007556h
TABLRD 92h
from 199E67h
INST(PC-2)
TBLRD Cycle1
TBLRD Cycle2
Advance Information
Opcode Fetch
ADDLW 55h
from 007558h
MOVLW
 2001 Microchip Technology Inc.
PIC18C601/801
6.3
Table Write
Table Write operations store data from the data memory space into external program memory.
PIC18C601/801devices perform Table Writes one byte
at a time. Table Writes to external memory are two-cycle
instructions, unless wait states are enabled. The last
cycle writes the data to the external memory location.
16-bit interface Table Writes depend on the type of
external device that is connected and the WM<1:0>
bits in the MEMCON register (See Figure 5-2).
Example 6-2 describes how to use TBLWT.
EXAMPLE 6-2:
; Write
CLRF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
TBLWT*
TABLE WRITE CODE EXAMPLE
a byte to location 0020h
TBLPTRU
; clear upper 5 bits of TBLPTR
TBLPTRH
; clear higher 8 bits of TBLPTR
20h
; Load 20h into
TBLPTRL
; TBLPTRL
55h
; Load 55h into
TBLAT
; TBLAT
; Write it
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 77
PIC18C601/801
6.3.1
8-BIT EXTERNAL TABLE WRITES
When the external bus is 8-bit, the byte-wide Table
Write exactly corresponds to the bus length and there
are no special considerations required.
The WRL signal is used as the active write signal.
Figure 6-6 and Figure 6-7 show the timings associated
with the 8-bit modes.
FIGURE 6-6:
TBLWT EXTERNAL INTERACE TIMING (8-BIT MULTIPLEXED MODE)
Q1
Q2
A<19:8>
AD<7:0>
Q3
Q4
Q1
Q2
03Ah
AAh
08h
Q3
Q4
Q1
Q2
03Ah
00h
ABh
55h
Q3
Q4
Q1
Q2
CCFh
0Eh
33h
Q3
Q4
03Ah
92h
ACh
55h
0Fh
BA0
ALE
OE
WRH ’1’
WRL
Memory
Cycle
Instruction
Execution
DS39541A-page 78
Opcode Fetch
TBLWT*
from 007554h
Opcode Fetch
MOVLW 55h
from 007556h
INST(PC-2)
TBLWT Cycle1
TBLWT 92h
to 199E67h
TBLWT Cycle2
Advance Information
Opcode Fetch
ADDLW 55h
from 007558h
MOVLW
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 6-7:
TBLWT EXTERNAL INTERFACE TIMING (8-BIT DE-MULTIPLEXED MODE)
Q1
A<19:8>
Q2
Q3
Q4
08h
Q2
Q3
Q4
Q1
Q2
03Ah
03Ah
AD<7:0>
Q1
00h
55h
Q3
Q4
CCFh
0Eh
Q1
Q2
Q3
Q4
03Ah
92h
55h
0Fh
BA0
ALE
OE
WRH ’1’
WRL
Memory
Cycle
Instruction
Execution
Opcode Fetch
TBLWT*
from 007554h
Opcode Fetch
MOVLW 55h
from 007556h
INST(PC-2)
TBLWT Cycle1
 2001 Microchip Technology Inc.
TBLWT 92h
to 199E67h
TBLWT Cycle2
Advance Information
Opcode Fetch
ADDLW 55h
from 007558h
MOVLW
DS39541A-page 79
PIC18C601/801
6.3.2
16-BIT EXTERNAL TABLE WRITE
(BYTE WRITE MODE)
This mode allows Table Writes to byte-wide external
memories. During a TBLWT cycle, the TABLAT data is
presented on the upper and lower byte of the
AD<15:0> bus. The appropriate WRH or WRL line is
strobed based on the LSb of the TBLPTR. Figure 6-8
shows the timing associated with this mode.
FIGURE 6-8:
TBLWT EXTERNAL INTERFACE TIMING (16-BIT BYTE WRITE MODE)
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
A<19:16>
AD<15:0>
0h
0h
3AAAh
000Dh
3AABh
Ch
6FF4h
CF33h
0h
5656h
3AACh
0h
000Ch
3AADh
Ch
0E55h
CF33h
9292h
BA0
ALE
OE
WRH
WRL
UB
LB
Memory
Cycle
Instruction
Execution
Opcode Fetch
Opcode Fetch
TBLWT 56h
Opcode Fetch
Opcode Fetch
TBLWT 92h
TBLWT*+
from 007554h
MOVWF TABLAT
from 007556h
to 199E66h
TBLWT*
from 007558h
MOVLW 55h
from 00755Ah
to 199E67h
INST(PC-2)
TBLWT*+ Cycle1
TBLWT*+ Cycle2
MOVWF
TBLWT* Cycle1
TBLWT* Cycle2
DS39541A-page 80
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
6.3.3
EXTERNAL TABLE WRITE IN 16-BIT
WORD WRITE MODE
This mode allows Table Writes to any type of wordwide external memories.
This method makes a distinction between TBLWT
cycles to even or odd addresses.
During a TBLWT cycle to an even address, where
TBLPTR<0> = 0, the TABLAT data is transferred to a
holding latch and the external address data bus is tristated for the data portion of the bus cycle. No write
signals are activated.
FIGURE 6-9:
During a TBLWT cycle to an odd address, where
TBLPTR<0> = 1, the TABLAT data is presented on the
upper byte of the AD<15:0> bus. The contents of the
holding latch are presented on the lower byte of the
AD<15:0> bus. The WRH line is strobed for each
write cycle and the WRL line is unused. The BA0 line
indicates the LSb of TBLPTR, but it is unnecessary.
The UB and LB lines are active to select both bytes.
The obvious limitation to this method is that the TBLWT
must be done in pairs on a specific word boundary to
correctly write a word location.
Figure 6-9 shows the timing associated with this mode.
TBLWT EXTERNAL INTERFACE TIMING (16-BIT WORD WRITE MODE)
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
A<19:16>
AD<15:0>
0h
0h
3AAAh
3AABh
Ch
0h
0h
Ch
CF33h
3AACh
Opcode Fetch
TBLWT 56h
Opcode Fetch
Opcode Fetch
TBLWT 92h
MOVWF TABLAT
from 007556h
to 199E66h
TBLWT*
from 007558h
MOVLW 55h
from 00755Ah
to 199E67h
MOVWF
TBLWT* Cycle1
TBLWT* Cycle2
000Dh
6FF4h
000Ch
3AADh
0E55h
CF33h
9256h
BA0
ALE
OE
WRH
WRL ’1’
UB
LB
Memory
Cycle
Instruction
Execution
Opcode Fetch
TBLWT*+
from 007554h
INST(PC-2)
TBLWT*+ Cycle1 TBLWT*+ Cycle2
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 81
PIC18C601/801
6.3.4
16-BIT EXTERNAL TABLE WRITE
(BYTE SELECT MODE)
WRL line is unused. The BA0 or UB or UL lines are
used to select the byte to be written, based on the LSb
of the TBLPTR.
This mode allows Table Writes to word-wide external
memories that have byte selection capabilities. This
generally includes word-wide FLASH devices and
word-wide static RAM devices.
JEDEC standard flash memories will require a I/O port
line to become a BYTE/WORD input signal and will
use the BA0 signal as a byte address. JEDEC standard static RAM memories will use the UB or UL signals to select the byte.
During a TBLWT cycle, the TABLAT data is presented
on the upper and lower byte of the AD<15:0> bus.
The WRH line is strobed for each write cycle and the
FIGURE 6-10:
Figure 6-10 shows the timing associated with this mode.
TBLWT EXTERNAL INTERFACE TIMING (16-BIT BYTE SELECT MODE)
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
A<19:16>
AD<15:0>
0h
0h
3AAAh
000Dh
3AABh
Ch
6FF4h
CF33h
0h
5656h
3AACh
0h
000Ch
3AADh
Ch
0E55h
CF33h
9292h
BA0
ALE
OE
WRH
WRL ’1’
UB
LB
Memory
Cycle
Instruction
Execution
Opcode Fetch
Opcode Fetch
TBLWT 56h
Opcode Fetch
Opcode Fetch
TBLWT 92h
TBLWT*+
from 007554h
MOVWF TABLAT
from 007556h
to 199E66h
TBLWT*
from 007558h
MOVLW 55h
from 00755Ah
to 199E67h
MOVWF
TBLWT* Cycle1
TBLWT* Cycle2
INST(PC-2)
DS39541A-page 82
TBLWT*+ Cycle1 TBLWT*+ Cycle2
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
6.4
Long Writes
The WAIT<1:0> bits in the MEMCON register will select
0, 1, 2, or 3 extra TCY cycles per TBLRD/TBWLT cycle.
The wait will occur on Q4.
Long writes will not be supported on the PIC18C601/801
to program FLASH configuration memory. The configuration locations can only be programmed in ICSP mode.
6.5
The default setting of the wait on power-up is to assert
a maximum wait of 3TCY cycles. This insures that slow
memories will work in Microprocessor mode immediately after RESET.
External Wait Cycles
The Table Reads and Writes have the capability to
insert wait states when accessing external memory.
These wait states only apply to the execution of a Table
Read or Write to external memory and not to instruction
fetches out of external memory. The guidelines presented in Section 5.0 must be followed to select the
proper memory speed grade for the device operating
frequency.
FIGURE 6-11:
Apparent Q
Actual Q
EXTERNAL INTERFACE TIMING (8-BIT MODE)
Q1 Q2
Q1 Q2
Q3
Q3
Q4
Q4
Q1
Q1
Q2
Q2
03Ah
A<19:8>
AD<7:0>
Figure 6-11 shows 8-bit external bus timing for a Table
Read with 2 wait cycles. Figure 6-12 shows 16-bit
external bus timing for a Table Read with 1 wait cycle.
ABh
55h
Q3
Q3
Q4
Q4
Q4
Q1
Q4
Q2
Q4
Q3
Q4
Q4
Q4
Q1
Q4
Q2
Q4
Q3
Q4
Q4
CCFh
0Eh
33h
92h
BA0
ALE
OE
2TCY Wait
Opcode Fetch
MOVLW 55h
from 007556h
 2001 Microchip Technology Inc.
Table Read
of 92h
from 199E67h
Advance Information
DS39541A-page 83
PIC18C601/801
FIGURE 6-12:
EXTERNAL INTERFACE TIMING (16-BIT MODE)
Apparent Q
Actual Q
Q1
Q1
Q2
Q2
A<19:16>
Q3
Q3
Q4
Q4
Q1
Q1
Q2
Q2
Q3
Q3
Q4
Q4
0h
3AABh
AD<15:0>
Q4
Q1
Q4
Q2
Q4
Q3
Q4
Q4
0Ch
0E55h
CF33h
9256h
BA0
ALE
OE
WRH
’1’
’1’
WRL
’1’
’1’
1TCY Wait
Opcode Fetch
MOVLW 55h
from 007556h
DS39541A-page 84
Table Read
of 92h
from 199E67h
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
7.0
8 X 8 HARDWARE MULTIPLIER
The performance increase allows the device to be used
in some applications previously reserved for Digital
Signal Processors.
An 8 x 8 hardware multiplier is included in the ALU of
PIC18C601/801 devices. By making the multiply a
hardware operation, it completes in a single instruction
cycle. This is an unsigned multiply that gives a 16-bit
result. The result is stored into the 16-bit product register pair (PRODH:PRODL). The multiplier does not
affect any flags in the STATUS register.
Table 7-1 shows a performance comparison between
enhanced devices using the single cycle hardware multiply, and performing the same function without the
hardware multiply.
Making the 8 x 8 multiplier execute in a single cycle
gives the following advantages:
• Higher computational throughput
• Reduces code size requirements for multiply
algorithms
TABLE 7-1:
PERFORMANCE COMPARISON
Routine
8 x 8 unsigned
8 x 8 signed
16 x 16 unsigned
16 x 16 signed
Multiply Method
Program
Memory
(Words)
Cycles
(Max)
Time
@ 25 MHz
@ 10 MHz
@ 4 MHz
Without hardware multiply
13
69
11.0 µs
27.6 µs
69.0 µs
Hardware multiply
1
1
160.0 ns
400.0 ns
1.0 µs
Without hardware multiply
33
91
14.6 µs
36.4 µs
91.0 µs
Hardware multiply
6
6
960.0 ns
2.4 µs
6.0 µs
Without hardware multiply
21
242
38.7 µs
96.8 µs
242.0 µs
Hardware multiply
24
24
3.8 µs
9.6 µs
24.0 µs
Without hardware multiply
52
254
40.6 µs
102.6 µs
254.0 µs
Hardware multiply
36
36
5.8 µs
14.4 µs
36.0 µs
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 85
PIC18C601/801
7.1
EXAMPLE 7-3:
Operation
Example 7-1 shows the sequence to perform an 8 x 8
unsigned multiply. Only one instruction is required
when one argument of the multiply is already loaded in
the WREG register.
Example 7-2 shows the sequence to do an 8 x 8 signed
multiply. To account for the sign bits of the arguments,
each argument’s most significant bit (MSb) is tested
and the appropriate subtractions are done.
EXAMPLE 7-1:
MOVFF
MULWF
8 x 8 UNSIGNED
MULTIPLY ROUTINE
ARG1, WREG
ARG2
EXAMPLE 7-2:
MOVFF
MULWF
ARG1, WREG
ARG2
BTFSC
SUBWF
ARG2, SB
PRODH
MOVFF
BTFSC
SUBWF
ARG2, WREG
ARG1, SB
PRODH
;
;
;
;
;
ARG1 * ARG2 ->
PRODH:PRODL
Test Sign Bit
PRODH = PRODH
- ARG1
; Test Sign Bit
; PRODH = PRODH
;
- ARG2
Example 7-3 shows the sequence to perform a 16 x 16
unsigned multiply. Equation 7-1 shows the algorithm
that is used. The 32-bit result is stored in 4 registers
RES3:RES0.
EQUATION 7-1:
RES3:RES0
=
=
DS39541A-page 86
16 x 16 UNSIGNED
MULTIPLICATION
ALGORITHM
ARG1H:ARG1L • ARG2H:ARG2L
(ARG1H • ARG2H • 216)+
(ARG1H • ARG2L • 28)+
(ARG1L • ARG2H • 28)+
(ARG1L • ARG2L)
MOVFF
MULWF
ARG1L, WREG
ARG2L
MOVFF
MOVFF
PRODH, RES1
PRODL, RES0
MOVFF
MULWF
ARG1H, WREG
ARG2H
MOVFF
MOVFF
PRODH, RES3
PRODL, RES2
MOVFF
MULWF
ARG1L, WREG
ARG2H
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1
PRODH, W
RES2
WREG
RES3
MOVFF
MULWF
ARG1H, WREG
ARG2L
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1
PRODH, W
RES2
WREG
RES3
; ARG1L * ARG2L ->
; PRODH:PRODL
;
;
;
; ARG1H * ARG2H ->
; PRODH:PRODL
;
;
;
;
; ARG1 * ARG2 ->
;
PRODH:PRODL
8 x 8 SIGNED MULTIPLY
ROUTINE
16 x 16 UNSIGNED
MULTIPLY ROUTINE
;
;
;
;
;
;
;
;
ARG1L * ARG2H ->
PRODH:PRODL
Add cross
products
;
;
;
;
;
;
;
;
;
;
ARG1H * ARG2L ->
PRODH:PRODL
Add cross
products
Example 7-4 shows the sequence to perform a 16 x 16
signed multiply. Equation 7-2 shows the algorithm
used. The 32-bit result is stored in four registers,
RES3:RES0. To account for the sign bits of the arguments, each argument pairs’ most significant bit (MSb)
is tested and the appropriate subtractions are done.
EQUATION 7-2:
16 x 16 SIGNED
MULTIPLICATION
ALGORITHM
RES3:RES0
= ARG1H:ARG1L • ARG2H:ARG2L
+
= (ARG1H • ARG2H • 216)
+
(ARG1H • ARG2L • 28)
(ARG1L • ARG2H • 28)
+
+
(ARG1L • ARG2L)
(-1 • ARG2H<7> • ARG1H:ARG1L • 216)
(-1 • ARG1H<7> • ARG2H:ARG2L • 216)
Advance Information
+
 2001 Microchip Technology Inc.
PIC18C601/801
EXAMPLE 7-4:
16 x 16 SIGNED
MULTIPLY ROUTINE
MOVFF
MULWF
ARG1L, WREG
ARG2L
MOVFF
MOVFF
PRODH, RES1
PRODL, RES0
MOVFF
MULWF
ARG1H, WREG
ARG2H
MOVFF
MOVFF
PRODH, RES3
PRODL, RES2
MOVFF
MULWF
ARG1L, WREG
ARG2H
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1
PRODH, W
RES2
WREG
RES3
MOVFF
MULWF
ARG1H, WREG
ARG2L
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1
PRODH, W
RES2
WREG
RES3
BTFSS
GOTO
MOVFF
SUBWF
MOVFF
SUBWFB
ARG2H, 7
SIGN_ARG1
ARG1L, WREG
RES2
ARG1H, WREG
RES3
; ARG2H:ARG2L neg?
; no, check ARG1
;
;
;
ARG1H, 7
CONT_CODE
ARG2L, WREG
RES2
ARG2H, WREG
RES3
; ARG1H:ARG1L neg?
; no, done
;
;
;
; ARG1L * ARG2L ->
;
PRODH:PRODL
;
;
;
; ARG1H * ARG2H ->
;
PRODH:PRODL
;
;
;
; ARG1L * ARG2H ->
;
PRODH:PRODL
;
; Add cross
;
products
;
;
;
;
;
; ARG1H * ARG2L ->
;
PRODH:PRODL
;
; Add cross
;
products
;
;
;
;
;
SIGN_ARG1
BTFSS
GOTO
MOVFF
SUBWF
MOVFF
SUBWFB
;
CONT_CODE
:
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 87
PIC18C601/801
NOTES:
DS39541A-page 88
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
8.0
INTERRUPTS
PIC18C601/801 devices have 15 interrupt sources and
an interrupt priority feature that allows each interrupt
source to be assigned a high priority level, or a low priority level. The high priority interrupt vector is at
000008h and the low priority interrupt vector is at
000018h. High priority interrupt events will override any
low priority interrupts that may be in progress.
There are 10 registers that are used to control interrupt
operation. These registers are:
•
•
•
•
•
•
•
RCON
INTCON
INTCON2
INTCON3
PIR1, PIR2
PIE1, PIE2
IPR1, IPR2
It is recommended that the Microchip header files supplied with MPLAB® IDE be used for the symbolic bit
names in these registers. This allows the assembler/
compiler to automatically take care of the placement of
these bits within the specified register.
Each interrupt source has three bits to control its operation. The functions of these bits are:
• Flag bit to indicate that an interrupt event
occurred
• Enable bit that allows program execution to
branch to the interrupt vector address when the
flag bit is set
• Priority bit to select high priority or low priority
When the IPEN bit is cleared (default state), the interrupt priority feature is disabled and interrupts are
compatible with PICmicro® mid-range devices. In Compatibility mode, the interrupt priority bits for each source
have no effect. The PEIE bit (INTCON register)
enables/disables all peripheral interrupt sources. The
GIE bit (INTCON register) enables/disables all interrupt
sources. All interrupts branch to address 000008h in
Compatibility mode.
When an interrupt is responded to, the Global Interrupt
Enable bit is cleared to disable further interrupts. If the
IPEN bit is cleared, this is the GIE bit. If interrupt priority levels are used, this will be either the GIEH or GIEL
bit. High priority interrupt sources can interrupt a low
priority interrupt.
The return address is pushed onto the stack and the
PC is loaded with the interrupt vector address
(000008h or 000018h). Once in the Interrupt Service
Routine, the source(s) of the interrupt can be determined by polling the interrupt flag bits. The interrupt
flag bits must be cleared in software before re-enabling
interrupts, to avoid recursive interrupts.
The "return from interrupt" instruction, RETFIE, exits
the interrupt routine and sets the GIE bit (GIEH or GIEL
if priority levels are used), which re-enables interrupts.
For external interrupt events, such as the INT pins or
the PORTB input change interrupt, the interrupt latency
will be three to four instruction cycles. The exact
latency is the same for one or two cycle instructions.
Individual interrupt flag bits are set, regardless of the
status of their corresponding enable bit or the GIE bit.
The interrupt priority feature is enabled by setting the
IPEN bit (RCON register). When interrupt priority is
enabled, there are two bits that enable interrupts globally. Setting the GIEH bit (INTCON register) enables
all interrupts that have the priority bit set. Setting the
GIEL bit (INTCON register) enables all interrupts that
have the priority bit cleared. When the interrupt flag,
enable bit and appropriate global interrupt enable bit
are set, the interrupt will vector immediately to address
000008h or 000018h, depending on the priority level.
Individual interrupts can be disabled through their corresponding enable bits.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 89
PIC18C601/801
FIGURE 8-1:
INTERRUPT LOGIC
TMR0IF
TMR0IE
TMR0IP
RBIF
RBIE
RBIP
INT0F
INT0E
INT1F
INT1E
INT1P
INT2F
INT2E
INT2P
Peripheral Interrupt Flag bit
Peripheral Interrupt Enable bit
Peripheral Interrupt Priority bit
Wake-up if in SLEEP mode
Interrupt to CPU
Vector to location
0008h
GIEH/GIE
TMR1IF
TMR1IE
TMR1IP
IPEN
IPEN
XXXXIF
XXXXIE
XXXXIP
GIEL/PEIE
IPEN
Additional Peripheral Interrupts
High Priority Interrupt Generation
Low Priority Interrupt Generation
Peripheral Interrupt Flag bit
Peripheral Interrupt Enable bit
Peripheral Interrupt Priority bit
TMR0IF
TMR0IE
TMR0IP
TMR1IF
TMR1IE
TMR1IP
RBIF
RBIE
RBIP
XXXXIF
XXXXIE
XXXXIP
Interrupt to CPU
Vector to Location
0018h
GIEL\PEIE
INT0F
INT0E
Additional Peripheral Interrupts
INT1F
INT1E
INT1P
INT2F
INT2E
INT2P
DS39541A-page 90
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
8.1
8.1.1
Control Registers
This section contains the control and status registers.
REGISTER 8-1:
INTCON REGISTERS
The INTCON Registers are readable and writable
registers, which contain various enable, priority, and
flag bits.
INTCON REGISTER
R/W-0
R/W-0
GIE/GIEH PEIE/GIEL
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-x
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
bit 7
bit 0
bit 7
GIE/GIEH: Global Interrupt Enable bit
When IPEN = 0:
1 = Enables all unmasked interrupts
0 = Disables all interrupts
When IPEN = 1:
1 = Enables all high priority interrupts
0 = Disables all high priority interrupts
bit 6
PEIE/GIEL: Peripheral Interrupt Enable bit
When IPEN = 0:
1 = Enables all unmasked peripheral interrupts
0 = Disables all peripheral interrupts
When IPEN = 1:
1 = Enables all low priority peripheral interrupts
0 = Disables all priority peripheral interrupts
bit 5
TMR0IE: TMR0 Overflow Interrupt Enable bit
1 = Enables the TMR0 overflow interrupt
0 = Disables the TMR0 overflow interrupt
bit 4
INT0IE: INT0 External Interrupt Enable bit
1 = Enables the INT0 external interrupt
0 = Disables the INT0 external interrupt
bit 3
RBIE: RB Port Change Interrupt Enable bit
1 = Enables the RB port change interrupt
0 = Disables the RB port change interrupt
bit 2
TMR0IF: TMR0 Overflow Interrupt Flag bit
1 = TMR0 register has overflowed (must be cleared in software)
0 = TMR0 register did not overflow
bit 1
INT0IF: INT0 External Interrupt Flag bit
1 = The INT0 external interrupt occurred (must be cleared in software)
0 = The INT0 external interrupt did not occur
bit 0
RBIF: RB Port Change Interrupt Flag bit
1 = At least one of the RB7:RB4 pins changed state (must be cleared in software)
0 = None of the RB7:RB4 pins have changed state
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Note:
 2001 Microchip Technology Inc.
x = Bit is unknown
Interrupt flag bits get set when an interrupt condition occurs, regardless of the state
of its corresponding enable bit, or the global enable bit. User software should ensure
the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature
allows software polling.
Advance Information
DS39541A-page 91
PIC18C601/801
REGISTER 8-2:
INTCON2 REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
U-0
R/W-1
U-0
R/W-1
RBPU
INTEDG0
INTEDG1
INTEDG2
—
TMR0IP
—
RBIP
bit 7
bit 0
bit 7
RBPU: PORTB Pull-up Enable bit
1 = All PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual port latch values
bit 6
INTEDG0: External Interrupt 0 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 5
INTEDG1: External Interrupt 1 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 4
INTEDG2: External Interrupt 2 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 3
Unimplemented: Read as ’0’
bit 2
TMR0IP: TMR0 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
Unimplemented: Read as ’0’
bit 0
RBIP: RB Port Change Interrupt Priority bit
1 = High priority
0 = Low priority
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Note:
DS39541A-page 92
x = Bit is unknown
Interrupt flag bits get set when an interrupt condition occurs, regardless of the state
of its corresponding enable bit, or the global enable bit. User software should ensure
the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature
allows software polling.
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 8-3:
INTCON3 REGISTER
R/W-1
R/W-1
U-0
R/W-0
R/W-0
U-0
R/W-0
R/W-0
INT2IP
INT1IP
—
INT2IE
INT1IE
—
INT2IF
INT1IF
bit 7
bit 0
bit 7
INT2IP: INT2 External Interrupt Priority bit
1 = High priority
0 = Low priority
bit 6
INT1IP: INT1 External Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5
Unimplemented: Read as ’0’
bit 4
INT2IE: INT2 External Interrupt Enable bit
1 = Enables the INT2 external interrupt
0 = Disables the INT2 external interrupt
bit 3
INT1IE: INT1 External Interrupt Enable bit
1 = Enables the INT1 external interrupt
0 = Disables the INT1 external interrupt
bit 2
Unimplemented: Read as ’0’
bit 1
INT2IF: INT2 External Interrupt Flag bit
1 = The INT2 external interrupt occurred (must be cleared in software)
0 = The INT2 external interrupt did not occur
bit 0
INT1IF: INT1 External Interrupt Flag bit
1 = The INT1 external interrupt occurred (must be cleared in software)
0 = The INT1 external interrupt did not occur
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Note:
 2001 Microchip Technology Inc.
x = Bit is unknown
Interrupt flag bits get set when an interrupt condition occurs, regardless of the state
of its corresponding enable bit, or the global enable bit. User software should ensure
the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature
allows software polling.
Advance Information
DS39541A-page 93
PIC18C601/801
8.1.2
PIR REGISTERS
8.1.3
The Peripheral Interrupt Request (PIR) registers contain the individual flag bits for the peripheral interrupts
(Register 8-5). There are two Peripheral Interrupt
Request (Flag) registers (PIR1, PIR2).
Note 1: Interrupt flag bits are set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit, or the global
enable bit, GIE (INTCON register).
2: User software should ensure the appropriate interrupt flag bits are cleared prior to
enabling an interrupt, and after servicing
that interrupt.
PIE REGISTERS
The Peripheral Interrupt Enable (PIE) registers contain
the individual enable bits for the peripheral interrupts
(Register 8-6). There are two two Peripheral Interrupt
Enable registers (PIE1, PIE2). When IPEN is clear, the
PEIE bit must be set to enable any of these peripheral
interrupts.
8.1.4
IPR REGISTERS
The Interrupt Priority (IPR) registers contain the individual priority bits for the peripheral interrupts (Register 8-9).
There are two Peripheral Interrupt Priority registers
(IPR1, IPR2). The operation of the priority bits requires
that the Interrupt Priority Enable bit (IPEN) be set.
8.1.5
RCON REGISTER
The Reset Control (RCON) register contains the bit that
is used to enable prioritized interrupts (IPEN).
REGISTER 8-4:
RCON REGISTER
R/W-0
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-0
U-0
IPEN
r
—
RI
TO
PD
POR
r
bit 7
bit 0
bit 7
IPEN: Interrupt Priority Enable bit
1 = Enable priority levels on interrupts
0 = Disable priority levels on interrupts (16CXXX compatibility mode)
bit 6
Reserved: Maintain as '0'
bit 5
Unimplemented: Read as '0'
bit 4
RI: RESET Instruction Flag bit
For details of bit operation, see Register 4-4
bit 3
TO: Watchdog Time-out Flag bit
For details of bit operation, see Register 4-4
bit 2
PD: Power-down Detection Flag bit
For details of bit operation, see Register 4-4
bit 1
POR: Power-on Reset Status bit
For details of bit operation, see Register 4-4
bit 0
Reserved: Maintain as '0'
Legend:
DS39541A-page 94
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 8-5:
PIR1 REGISTER
U-0
R/W-0
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
bit 7
bit 0
bit 7
Unimplemented: Read as ’0’
bit 6
ADIF: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed
(must be cleared in software)
0 = The A/D conversion is not complete
bit 5
RCIF: USART Receive Interrupt Flag bit
1 = The USART receive buffer, RCREG, is full
(cleared when RCREG is read)
0 = The USART receive buffer is empty
bit 4
TXIF: USART Transmit Interrupt Flag bit
1 = The USART transmit buffer, TXREG, is empty
(cleared when TXREG is written)
0 = The USART transmit buffer is full
bit 3
SSPIF: Master Synchronous Serial Port Interrupt Flag bit
1 = The transmission/reception is complete
(must be cleared in software)
0 = Waiting to transmit/receive
bit 2
CCP1IF: CCP1 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred
(must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred
(must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode
bit 1
TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
1 = TMR2 to PR2 match occurred
(must be cleared in software)
0 = No TMR2 to PR2 match occurred
bit 0
TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed
(must be cleared in software)
0 = TMR1 register did not overflow
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 95
PIC18C601/801
REGISTER 8-6:
PIR2 REGISTER
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
—
—
BCLIF
LVDIF
TMR3IF
CCP2IF
bit 7
bit 0
bit 7-4
Unimplemented: Read as’0’
bit 3
BCLIF: Bus Collision Interrupt Flag bit
1 = A bus collision occurred
(must be cleared in software)
0 = No bus collision occurred
bit 2
LVDIF: Low Voltage Detect Interrupt Flag bit
1 = A low voltage condition occurred
(must be cleared in software)
0 = The device voltage is above the Low Voltage Detect trip point
bit 1
TMR3IF: TMR3 Overflow Interrupt Flag bit
1 = TMR3 register overflowed
(must be cleared in software)
0 = TMR3 register did not overflow
bit 0
CCP2IF: CCPx Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred
(must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred
(must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode
Legend:
DS39541A-page 96
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 8-7:
PIE1 REGISTER
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
bit 7
bit 0
bit 7
Unimplemented: Read as ’0’
bit 6
ADIE: A/D Converter Interrupt Enable bit
1 = Enables the A/D interrupt
0 = Disables the A/D interrupt
bit 5
RCIE: USART Receive Interrupt Enable bit
1 = Enables the USART receive interrupt
0 = Disables the USART receive interrupt
bit 4
TXIE: USART Transmit Interrupt Enable bit
1 = Enables the USART transmit interrupt
0 = Disables the USART transmit interrupt
bit 3
SSPIE: Master Synchronous Serial Port Interrupt Enable bit
1 = Enables the MSSP interrupt
0 = Disables the MSSP interrupt
bit 2
CCP1IE: CCP1 Interrupt Enable bit
1 = Enables the CCP1 interrupt
0 = Disables the CCP1 interrupt
bit 1
TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
1 = Enables the TMR2 to PR2 match interrupt
0 = Disables the TMR2 to PR2 match interrupt
bit 0
TMR1IE: TMR1 Overflow Interrupt Enable bit
1 = Enables the TMR1 overflow interrupt
0 = Disables the TMR1 overflow interrupt
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 97
PIC18C601/801
REGISTER 8-8:
PIE2 REGISTER
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
—
—
BCLIE
LVDIE
TMR3IE
CCP2IE
bit 7
bit 0
bit 7-4
Unimplemented: Read as '0'
bit 3
BCLIE: Bus Collision Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 2
LVDIE: Low Voltage Detect Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 1
TMR3IE: TMR3 Overflow Interrupt Enable bit
1 = Enables the TMR3 overflow interrupt
0 = Disables the TMR3 overflow interrupt
bit 0
CCP2IE: CCP2 Interrupt Enable bit
1 = Enables the CCP2 interrupt
0 = Disables the CCP2 interrupt
Legend:
DS39541A-page 98
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 8-9:
IPR1 REGISTER
U-0
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
bit 7
bit 0
bit 7
Unimplemented: Read as ’0’
bit 6
ADIP: A/D Converter Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5
RCIP: USART Receive Interrupt Priority bit
1 = High priority
0 = Low priority
bit 4
TXIP: USART Transmit Interrupt Priority bit
1 = High priority
0 = Low priority
bit 3
SSPIP: Master Synchronous Serial Port Interrupt Priority bit
1 = High priority
0 = Low priority
bit 2
CCP1IP: CCP1 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
TMR2IP: TMR2 to PR2 Match Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0
TMR1IP: TMR1 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 99
PIC18C601/801
REGISTER 8-10:
IPR2 REGISTER
U-0
U-0
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-1
—
—
—
—
BCLIP
LVDIP
TMR3IP
CCP2IP
bit 7
bit 0
bit 7-4
Unimplemented: Read as '0'
bit 3
BCLIP: Bus Collision Interrupt Priority bit
1 = High priority
0 = Low priority
bit 2
LVDIP: Low Voltage Detect Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
TMR3IP: TMR3 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0
CCP2IP: CCP2 Interrupt Priority bit
1 = High priority
0 = Low priority
Legend:
DS39541A-page 100
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
8.1.6
INT INTERRUPTS
External interrupts on the RB0/INT0, RB1/INT1 and
RB2/INT2 pins are edge triggered: either rising, if the
corresponding INTEDGx bit is set in the INTCON2 register, or falling, if the INTEDGx bit is clear. When a valid
edge appears on the RBx/INTx pin, the corresponding
flag bit INTxIF is set. This interrupt can be disabled by
clearing the corresponding enable bit INTxIE. Flag bit
INTxIF must be cleared in software in the Interrupt Service Routine before re-enabling the interrupt. All external interrupts (INT0, INT1 and INT2) can wake-up the
processor from SLEEP, if bit INTxIE was set prior to
going into SLEEP. If the global interrupt enable bit GIE
is set, the processor will branch to the interrupt vector
following wake-up.
Interrupt priority for INT1 and INT2 is determined by the
value contained in the interrupt priority bits INT1IP
(INTCON3 register) and INT2IP (INTCON3 register).
There is no priority bit associated with INT0; it is always
a high priority interrupt source.
8.1.7
TMR0 INTERRUPT
In 8-bit mode (which is the default), an overflow
(0FFh → 00h) in the TMR0 register will set flag bit
TMR0IF. In 16-bit mode, an overflow (0FFFFh → 0000h)
EXAMPLE 8-1:
in the TMR0H:TMR0L registers will set flag bit TMR0IF.
The interrupt can be enabled/disabled by setting/clearing enable bit TMR0IE (INTCON register). Interrupt priority for Timer0 is determined by the value contained in the
interrupt priority bit TMR0IP (INTCON2 register). See
Section 10.0 for further details on the Timer0 module.
8.1.8
PORTB INTERRUPT-ON-CHANGE
An input change on PORTB<7:4> sets flag bit RBIF
(INTCON register). The interrupt can be enabled/
disabled by setting/clearing enable bit RBIE (INTCON
register). Interrupt priority for PORTB interrupt-onchange is determined by the value contained in the
interrupt priority bit RBIP (INTCON2 register).
8.2
Context Saving During Interrupts
During an interrupt, the return PC value is saved on the
stack. Additionally, the WREG, STATUS and BSR registers are saved on the fast return stack. If a fast return
from interrupt is not used (See Section 4.3), the user
may need to save the WREG, STATUS and BSR registers in software. Depending on the user’s application,
other registers may also need to be saved. Example 8-1
saves and restores the WREG, STATUS and BSR
registers during an Interrupt Service Routine.
SAVING STATUS, WREG AND BSR REGISTERS IN RAM
MOVWF
W_TEMP
MOVFF
STATUS, STATUS_TEMP
MOVFF
BSR, BSR_TEMP
;
; USER ISR CODE
;
MOVFF
BSR_TEMP, BSR
MOVF
W_TEMP, W
MOVFF
STATUS_TEMP, STATUS
 2001 Microchip Technology Inc.
; W_TEMP is in Low Access bank
; STATUS_TEMP located anywhere
; BSR located anywhere
; Restore BSR
; Restore WREG
; Restore STATUS
Advance Information
DS39541A-page 101
PIC18C601/801
NOTES:
DS39541A-page 102
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
9.0
I/O PORTS
EXAMPLE 9-1:
Depending on the device selected, there are up to 9
ports available. Some pins of the I/O ports are multiplexed with an alternate function from the peripheral
features on the device. In general, when a peripheral is
enabled, that pin may not be used as a general
purpose I/O pin.
Each port has three registers for its operation. These
registers are:
• TRIS register (data direction register)
• PORT register (reads the levels on the pins of the
device)
• LAT register (output latch)
CLRF
PORTA
CLRF
LATA
MOVLW
MOVWF
MOVLW
07h
ADCON1
0CFh
MOVWF
TRISA
INITIALIZING PORTA
;
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTA by
clearing output
data latches
Alternate method
to clear output
data latches
Configure A/D
for digital inputs
Value used to
initialize data
direction
Set RA3:RA0 as inputs
RA5:RA4 as outputs
The data latch (LAT register) is useful for read-modifywrite operations on the value that the I/O pins are driving.
9.1
FIGURE 9-1:
PORTA, TRISA and LATA
Registers
PORTA is a 6-bit wide, bi-directional port. The corresponding data direction register is TRISA. Setting a
TRISA bit (= 1) will make the corresponding PORTA pin
an input (i.e., put the corresponding output driver in a
Hi-Impedance mode). Clearing a TRISA bit (= 0) will
make the corresponding PORTA pin an output (i.e., put
the contents of the output latch on the selected pin).
On a Power-on Reset, these pins are configured as
analog inputs and read as '0'.
Reading the PORTA register reads the status of the
pins, whereas writing to it will write to the port latch.
RA3:RA0 AND RA5 PINS
BLOCK DIAGRAM
RD LATA
Data
Bus
D
Q
VDD
WR LATA
or
WR PORTA
CK
Q
D
CK
Note:
I/O pin(1)
VSS
Analog
Input
Mode
Q
TRIS Latch
The RA4 pin is multiplexed with the Timer0 module
clock input to become the RA4/T0CKI pin. The RA4/
T0CKI pin is a Schmitt Trigger input and an open drain
output. All other RA port pins have TTL input levels and
full CMOS output drivers.
The TRISA register controls the direction of the RA
pins, even when they are being used as analog inputs.
The user must ensure the bits in the TRISA register are
maintained set when using them as analog inputs.
N
Q
WR TRISA
Read-modify-write operations on the LATA register,
reads and writes the latched output value for PORTA.
The other PORTA pins are multiplexed with analog
inputs and the analog VREF+ and VREF- inputs. The
operation of each pin is selected by clearing/setting the
control bits in the ADCON1 register (A/D Control
Register1). On a Power-on Reset, these pins are configured as analog inputs and read as '0'.
P
Data Latch
RD TRISA
Q
D
TTL
Input
Buffer
EN
RD PORTA
SS Input (RA5 only)
To A/D Converter and LVD Modules
Note 1: I/O pins have diode protection to VDD and VSS.
On a Power-on Reset, PORTA pins
RA3:RA0 and RA5 default to analog inputs.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 103
PIC18C601/801
FIGURE 9-2:
RA4/T0CKI PIN BLOCK
DIAGRAM
RD LATA
Data
Bus
Q
D
WR LATA
or
WR PORTA
CK
Q
WR TRISA
D
Q
CK
Q
I/O pin(1)
N
Data Latch
VSS
Schmitt
Trigger
Input
Buffer
TRIS Latch
RD TRISA
Q
D
ENEN
RD PORTA
TMR0 Clock Input
Note 1: I/O pin has diode protection to VSS only.
TABLE 9-1:
PORTA FUNCTIONS
Name
Bit#
Buffer
Function
RA0/AN0
bit0
TTL
Input/output or analog input
RA1/AN1
bit1
TTL
Input/output or analog input
RA2/AN2/VREF-
bit2
TTL
Input/output or analog input or VREF-
RA3/AN3/VREF+
bit3
TTL
Input/output or analog input or VREF+
RA4/T0CKI
bit4
RA5/SS/AN4/LVDIN
bit5
ST/OD Input/output or external clock input for Timer0, output is open drain type
TTL
Input/output or slave select input for synchronous serial port or analog
input or low voltage detect input
Legend: TTL = TTL input, ST = Schmitt Trigger input, OD = Open Drain
TABLE 9-2:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Value on
POR,
BOR
Value on all
other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PORTA
—
—
RA5
RA4
RA3
RA2
RA1
RA0
LATA
—
Latch A Data Output Register
-xxx xxxx -uuu uuuu
TRISA
—
PORTA Data Direction Register
-111 1111 -111 1111
ADCON1
—
—
VCFG1 VCFG0
PCFG3
PCFG2
PCFG1
--0x 0000 --uu uuuu
PCFG0 --00 0000 --uu uuuu
Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'.
Shaded cells are not used by PORTA.
DS39541A-page 104
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
9.2
PORTB, TRISB and LATB
Registers
PORTB is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISB. Setting a
TRISB bit (= 1) will make the corresponding PORTB pin
an input (i.e., put the corresponding output driver in a
Hi-Impedance mode). Clearing a TRISB bit (= 0) will
make the corresponding PORTB pin an output ( i.e.,
put the contents of the output latch on the selected pin).
Read-modify-write operations on the LATB register
read and write the latched output value for PORTB.
EXAMPLE 9-2:
CLRF
PORTB
CLRF
LATB
MOVLW
0CFh
MOVWF
TRISB
INITIALIZING PORTB
;
;
;
;
;
;
;
;
;
;
;
;
FIGURE 9-3:
Initialize PORTB by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RB3:RB0 as inputs
RB5:RB4 as outputs
RB7:RB6 as inputs
RB7:RB4 PINS BLOCK
DIAGRAM
VDD
RBPU(2)
Data Bus
WR LATB
or
WR PORTB
WR TRISB
Weak
P Pull-up
Data Latch
D
Q
I/O pin(1)
CK
TRIS Latch
D
Q
TTL
Input
Buffer
CK
Each of the PORTB pins has a weak internal pull-up. A
single control bit can turn on all the pull-ups. This is performed by clearing bit RBPU (INTCON2 register). The
weak pull-up is automatically turned off when the port
pin is configured as an output. The pull-ups are
disabled on a Power-on Reset.
Pin RB3 is multiplexed with the CCP input/output. The
weak pull-up for RB3 is disabled when the RB3 pin is
configured as CCP pin. By disabling the weak pull-up
when pin is configured as CCP, allows the remaining
weak pull-up devices of PORTB to be used while the
CCP is being used.
Four of PORTB’s pins, RB7:RB4, have an interrupt-onchange feature. Only pins configured as inputs can
cause this interrupt to occur (i.e., any RB7:RB4 pin
configured as an output is excluded from the interrupton-change comparison). The input pins (of RB7:RB4)
are compared with the old value latched on the last
read of PORTB. The “mismatch” outputs of RB7:RB4
are OR’d together to generate the RB Port Change
Interrupt with flag bit RBIF (INTCON register).
This interrupt can wake the device from SLEEP. The
user, in the Interrupt Service Routine, can clear the
interrupt in the following manner:
a)
b)
Any read or write of PORTB (except with the
MOVFF instruction). This will end the mismatch
condition.
Clear flag bit RBIF.
A mismatch condition will continue to set flag bit RBIF.
Reading PORTB will end the mismatch condition and
allow flag bit RBIF to be cleared.
The interrupt-on-change feature is recommended for
wake-up on key depression operation and operations
where PORTB is only used for the interrupt-on-change
feature. Polling of PORTB is not recommended while
using the interrupt-on-change feature.
ST
Buffer
RD TRISB
RD LATB
Latch
Q
D
EN
RD PORTB
Q1
Set RBIF
From other
RB7:RB4 pins
Q
D
RD PORTB
EN
Q3
RBx/INTx
Note 1: I/O pins have diode protection to VDD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU bit (INTCON2 register).
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 105
PIC18C601/801
FIGURE 9-4:
RB2:RB0 PINS BLOCK
DIAGRAM
VDD
RBPU(2)
Data Bus
Weak
P Pull-up
Data Latch
D
Q
I/O pin(1)
WR Port
CK
TRIS Latch
D
Q
WR TRIS
TTL
Input
Buffer
CK
RD TRIS
Q
RD Port
RBx/INTx
D
EN
Schmitt Trigger
Buffer
RD Port
Note 1: I/O pins have diode protection to VDD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS
bit(s) and clear the RBPU bit (INTCON2 register).
FIGURE 9-5:
RB3 PIN BLOCK DIAGRAM
VDD
RBPU(2)
CCP Enable
Weak
P Pull-up
CCP Output
1
VDD
P
Enable
CCP Output
0
Data Latch
Data Bus
D
WR LATB or
WR PORTB
CK
I/O pin(1)
Q
N
VSS
TRIS Latch
Q
D
WR TRISB
CK
TTL
Input
Buffer
Q
RD TRISB
RD LATB
Q
RD PORTB
D
EN
RD PORTB
CCP2 Input
Schmitt Trigger
Buffer
Note 1: I/O pin has diode protection to VDD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s) and clear the RBPU bit (INTCON2<7>).
DS39541A-page 106
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 9-3:
PORTB FUNCTIONS
Name
Bit#
Buffer
RB0/INT0
bit0
TTL/ST(1)
Input/output pin or external interrupt 0 input. Internal software
programmable weak pull-up.
RB1/INT1
bit1
TTL/ST(1)
Input/output pin or external interrupt 1 input. Internal software
programmable weak pull-up.
RB2/INT2
bit2
TTL/ST(1)
Input/output pin or external interrupt 2 input. Internal software
programmable weak pull-up.
RB3/CCP2
bit3
TTL/ST(3)
Input/output pin or Capture2 input or Capture2 output or PWM2 output.
Internal software programmable weak pull-up.
RB4
bit4
TTL
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up.
RB5
bit5
TTL
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up.
RB6
bit6
TTL/ST(2)
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up. Serial programming clock.
RB7
bit7
TTL/ST(2)
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up. Serial programming data.
Legend:
Note 1:
2:
3:
Function
TTL = TTL input, ST = Schmitt Trigger input
This pin is a Schmitt Trigger input when configured as the external interrupt.
This pin is a Schmitt Trigger input when used in Serial Programming mode.
This pin is a Schmitt Trigger input when used in a Capture input.
TABLE 9-4:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx uuuu uuuu
LATB
LATB Data Output Register
TRISB
PORTB Data Direction Register
INTCON
GIE/GIEH PEIE/GIEL
INTCON2
RBPU
INTEDG0
INTCON3
INT2IP
INT1IP
xxxx xxxx uuuu uuuu
1111 1111 1111 1111
TMR0IE
INT0IE
RBIE
TMR0IF INT0IF
INTEDG1 INTEDG2 INTEDG3 TMR0IP
—
INT2IE
INT1IE
—
—
RBIF
0000 000x 0000 000u
RBIP
1111 1111 1111 1111
INT2IF INT1IF 1100 0000 1100 0000
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTD.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 107
PIC18C601/801
9.3
PORTC, TRISC and LATC
Registers
The pin override value is not loaded into the TRIS register. This allows read-modify-write of the TRIS register,
without concern due to peripheral overrides.
PORTC is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISC. Setting a
TRISC bit (= 1) will make the corresponding PORTC
pin an input (i.e., put the corresponding output driver in
a Hi-Impedance mode). Clearing a TRISC bit (= 0) will
make the corresponding PORTC pin an output (i.e., put
the contents of the output latch on the selected pin).
EXAMPLE 9-3:
Read-modify-write operations on the LATC register,
read and write the latched output value for PORTC.
PORTC is multiplexed with several peripheral functions
(Table 9-5). PORTC pins have Schmitt Trigger input
buffers.
CLRF
PORTC
CLRF
LATC
MOVLW
0CFh
MOVWF
TRISC
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTC pin. Some
peripherals override the TRIS bit to make a pin an output, while other peripherals override the TRIS bit to make
a pin an input. The user should refer to the corresponding peripheral section for the correct TRIS bit settings.
FIGURE 9-6:
INITIALIZING PORTC
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTC by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RC3:RC0 as inputs
RC5:RC4 as outputs
RC7:RC6 as inputs
PORTC BLOCK DIAGRAM (PERIPHERAL OUTPUT OVERRIDE)
Peripheral Out Select
Peripheral Data Out
VDD
0
P
RD LATC
Data Bus
WR LATC
or
WR PORTC
WR TRISC
D
Q
CK
Q
1
I/O pin(1)
TRIS OVERRIDE
Data Latch
D
Q
CK
Q
N
VSS
TRIS
Override
TRIS Latch
Peripheral Enable
Schmitt
Trigger
RD TRISC
Q
D
EN
Pin
Override Peripheral
RC0
Yes
Timer1 OSC for
Timer1/Timer3
RC1
Yes
Timer1 OSC for
Timer1/Timer3
RC2
No
—
RC3
Yes
SPI/I2C Master Clock
RC4
Yes
I2C Data Out
RC5
Yes
SPI Data Out
RC6
Yes
USART Async Xmit,
Sync Clock
RC7
Yes
USART Sync Data Out
RD PORTC
Peripheral Data In
Note 1: I/O pins have diode protection to VDD and VSS.
DS39541A-page 108
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 9-5:
PORTC FUNCTIONS
Name
Bit#
Buffer Type
RC0/T1OSO/T13CKI
bit0
ST
Function
Input/output port pin or Timer1 oscillator output or Timer1/Timer3
clock input.
RC1/T1OSI
bit1
ST
Input/output port pin, Timer1 oscillator input.
RC2/CCP1
bit2
ST
Input/output port pin or Capture1 input/Compare1 output/
PWM1 output.
RC3/SCK/SCL
bit3
ST
Input/output port pin or synchronous serial clock for SPI/I2C.
RC4/SDI/SDA
bit4
ST
Input/output port pin or SPI Data in (SPI mode) or Data I/O
(I2C mode).
RC5/SDO
bit5
ST
Input/output port pin or Synchronous Serial Port Data output.
RC6/TX/CK
bit6
ST
Input/output port pin, Addressable USART Asynchronous Transmit, or
Addressable USART Synchronous Clock.
RC7/RX/DT
bit7
ST
Input/output port pin, Addressable USART Asynchronous Receive, or
Addressable USART Synchronous Data.
Legend: ST = Schmitt Trigger input
TABLE 9-6:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on all
other
RESETS
PORTC
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
xxxx xxxx
uuuu uuuu
LATC
LATC Data Output Register
xxxx xxxx
uuuu uuuu
TRISC
PORTC Data Direction Register
1111 1111
1111 1111
Legend: x = unknown, u = unchanged
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 109
PIC18C601/801
9.4
FIGURE 9-7:
PORTD, TRISD and LATD
Registers
PORTD is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISD. Setting a
TRISD bit (= 1) will make the corresponding PORTD
pin an input (i.e., put the corresponding output driver in
a Hi-Impedance mode). Clearing a TRISD bit (= 0) will
make the corresponding PORTD pin an output (i.e., put
the contents of the output latch on the selected pin).
Read-modify-write operations on the LATD register
reads and writes the latched output value for PORTD.
PORTD is an 8-bit port with Schmitt Trigger input buffers. Each pin is individually configurable as an input or
output.
RD LATD
Data Bus
WR LATD
or
WR PORTD
On a Power-on Reset, PORTD defaults to
the system bus.
WR TRISD
CLRF
PORTD
CLRF
LATD
MOVLW
0CFh
MOVWF
TRISD
DS39541A-page 110
Q
I/O pin
CK
Data Latch
Q
Schmitt
Trigger
Input
Buffer
CK
TRIS Latch
RD TRISD
Q
D
ENEN
RD PORTD
Note:
EXAMPLE 9-4:
D
D
PORTD is multiplexed with the system bus and is available only when the system bus is disabled, by setting
EBIDS bit in register MEMCON. When operating as
the system bus, PORTD is the low order byte of the
address/data bus (AD7:AD0), or as the low order
address byte (A15:A8) if the address and data buses
are de-multiplexed.
Note:
PORTD BLOCK DIAGRAM
IN I/O MODE
I/O pins have diode protection to VDD and VSS.
INITIALIZING PORTD
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTD by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RD3:RD0 as inputs
RD5:RD4 as outputs
RD7:RD6 as inputs
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 9-8:
PORTD BLOCK DIAGRAM IN SYSTEM BUS MODE
Q
D
ENEN
RD PORTD
RD LATD
Data Bus
D
Q
Port
Data
WR LATD
or
PORTD
1
CK
Data Latch
D
WR TRISD
I/O pin(1)
0
Q
TTL
Input
Buffer
CK
TRIS Latch
Bus Enable
System Bus Data/TRIS Out
Control
Drive Bus
RD TRISD
Instruction Register
Instruction Read
Note 1: I/O pins have protection diodes to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 111
PIC18C601/801
TABLE 9-7:
PORTD FUNCTIONS
Name
Bit#
Buffer Type
RD0/AD0/A0(2)
bit0
ST/TTL(1)
Input/output port pin or system bus bit 0
RD1/AD1/A1(2)
bit1
ST/TTL(1)
Input/output port pin or system bus bit 1
(2)
bit2
ST/TTL
(1)
Input/output port pin or system bus bit 2
RD3/AD3/A3(2)
bit3
ST/TTL(1)
Input/output port pin or system bus bit 3
RD4/AD4/A4(3)
bit4
ST/TTL(1)
Input/output port pin or system bus bit 4
RD5/AD5/A5(2)
bit5
ST/TTL(1)
Input/output port pin or system bus bit 5
(2)
bit6
ST/TTL
(1)
Input/output port pin or system bus bit 6
RD7/AD7/A7(2)
bit7
ST/TTL(1)
Input/output port pin or system bus bit 7
RD2/AD2/A2
RD6/AD6/A6
Function
Legend: ST = Schmitt Trigger input, TTL = TTL input
Note 1: Input buffers are Schmitt Triggers when in I/O mode and TTL buffers when in System Bus mode.
2: RDx is used as a multiplexed address/data bus for PIC18C601 and PIC18C801 in 16-bit mode, and as an
address only for PIC18C801 in 8-bit mode.
TABLE 9-8:
Name
PORTD
SUMMARY OF REGISTERS ASSOCIATED WITH PORTD
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on all
other
RESETS
RD7
RD6
RD5
RD4
RD3
RD2
RD1
RD0
xxxx xxxx
uuuu uuuu
xxxx xxxx
uuuu uuuu
1111 1111
1111 1111
0000 --00
0000 --00
LATD
LATD Data Output Register
TRISD
PORTD Data Direction Register
MEMCON
EBDIS
PGRM
WAIT1
WAIT0
—
—
WM1
WM0
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by PORTD.
DS39541A-page 112
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
9.5
PORTE, TRISE and LATE
Registers
byte of the address/data bus (AD15:AD8), or as the
high order address byte (A15:A8), if address and data
buses are de-multiplexed.
PORTE is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISE. Setting a
TRISE bit (= 1) will make the corresponding PORTE pin
an input (i.e., put the corresponding output driver in a
Hi-Impedance mode). Clearing a TRISE bit (= 0) will
make the corresponding PORTE pin an output (i.e., put
the contents of the output latch on the selected pin).
Note:
EXAMPLE 9-5:
Read-modify-write operations on the LATE register
reads and writes the latched output value for PORTE.
PORTE is an 8-bit port with Schmitt Trigger input buffers. Each pin is individually configurable as an input or
output. PORTE is multiplexed with several peripheral
functions (Table 9-9).
PORTE is multiplexed with the system bus and is available only when the system bus is disabled, by setting
EBDIS bit in register MEMCON. When operating as the
system bus, PORTE is configured as the high order
FIGURE 9-9:
On Power-on Reset, PORTE defaults to
the system bus.
CLRF
PORTE
CLRF
LATE
MOVLW
03h
MOVWF
TRISE
INITIALIZING PORTE
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTE by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RE1:RE0 as inputs
RE7:RE2 as outputs
PORTE BLOCK DIAGRAM IN I/O MODE
Peripheral Out Select
Peripheral Data Out
VDD
0
P
1
I/O pin(1)
RD LATE
Data Bus
WR LATE
or
WR PORTE
WR TRISE
D
Q
CK
Q
Data Latch
D
Q
CK
Q
N
TRIS Latch
Peripheral Enable
TRIS OVERRIDE
VSS
TRIS
Override
Schmitt
Trigger
RD TRISE
Pin
Override
Peripheral
RE0
Yes
External Bus
RE1
Yes
External Bus
RE2
Yes
External Bus
RE3
Yes
External Bus
D
RE4
Yes
External Bus
EN
RE5
Yes
External Bus
RD PORTE
RE6
Yes
External Bus
Peripheral Data In
RE7
Yes
External Bus
Q
Note 1: I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 113
PIC18C601/801
FIGURE 9-10:
PORTE BLOCK DIAGRAM IN SYSTEM BUS MODE
Q
D
ENEN
RD PORTE
RD LATD
Data Bus
D
Q
Port
Data
WR LATE
or
PORTE
1
CK
Data Latch
TRIS Latch
D
WR TRISE
External Enable
System Bus
Control
I/O pin(1)
0
Q
TTL
Input
Buffer
CK
RD TRISE
Data/Address Out
Drive System
To Instruction Register
Instruction Read
Note 1: I/O pins have diode protection to VDD and VSS.
DS39541A-page 114
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 9-9:
PORTE FUNCTIONS
Name
Bit#
Buffer Type
RE0/AD8/A8(2)
Function
ST/TTL(1)
bit0
Input/output port pin or Address/Data bit 8
RE1/AD9/A9(2)
bit1
ST/TTL(1)
Input/output port pin or Address/Data bit 9
RE2/AD10/A10(2)
bit2
ST/TTL(1)
Input/output port pin or Address/Data bit 10
(2)
(1)
RE3/AD11/A11
bit3
ST/TTL
Input/output port pin or Address/Data bit 11
RE4/AD12/A12(2)
bit4
ST/TTL(1)
Input/output port pin or Address/Data bit 12
RE5/AD13/A13(2)
bit5
ST/TTL(1)
Input/output port pin or Address/Data bit 13
RE6/AD14/A14(2)
bit6
ST/TTL(1)
Input/output port pin or Address/Data bit 14
(2)
(1)
RE7/AD15/A15
bit7
ST/TTL
Input/output port pin or Address/Data bit 15
Legend: ST = Schmitt Trigger input, TTL = TTL input
Note 1: Input buffers are Schmitt Triggers when in I/O mode and TTL buffers when in System Bus mode.
2: REx is used as a multiplexed address/data bus for PIC18C601 and PIC18C801 in 16-bit mode, and as an
address only for PIC18C801 in 8-bit mode.
TABLE 9-10:
Name
TRISE
PORTE
LATE
MEMCON
SUMMARY OF REGISTERS ASSOCIATED WITH PORTE
Value on:
POR,
BOR
Value on all
other
RESETS
PORTE Data Direction Control Register
1111 1111
1111 1111
Read PORTE pin/Write PORTE Data Latch
xxxx xxxx
uuuu uuuu
Read PORTE Data Latch/Write PORTE Data Latch
xxxx xxxx
uuuu uuuu
0000 --00
0000 --00
Bit 7
EBDIS
Bit 6
PGRM
Bit 5
WAIT1
Bit 4
WAIT0
Bit 3
—
Bit 2
—
Bit 1
WM1
Bit 0
WM0
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTE.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 115
PIC18C601/801
9.6
EXAMPLE 9-7:
PORTF, LATF, and TRISF
Registers
PORTF is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISF. Setting a
TRISF bit (= 1) will make the corresponding PORTF pin
an input (i.e., put the corresponding output driver in a
Hi-Impedance mode). Clearing a TRISF bit (= 0) will
make the corresponding PORTF pin an output (i.e., put
the contents of the output latch on the selected pin).
Read-modify-write operations on the LATF register
reads and writes the latched output value for PORTF.
PORTF pins, RF2:RF0, are multiplexed with analog
inputs. The operation of these pins are selected by
ADCON0 and ADCON1 registers.
PORTF pins, RF3 and RF5, are multiplexed with two of
the integrated chip select signals CSIO and CS1. For
PIC18C801, pin RF4 is multiplexed with chip select signal CS2, while for PIC18C601, it is multiplexed with
system bus signal A16. For PIC18C801 devices, both
CSEL2 and CSELIO registers must set to all zero, to
enable these pins as I/O pins, while for PIC18C601
devices, only CSELIO register needs to be set to zero.
For PIC18C601 devices, pin RF4 can only be configured as I/O when the EBDIS bit is set and execution is
taking place in internal Boot RAM.
PORTF pins, RF7:RF6, are multiplexed with the system bus control signal UB and LB, respectively, when a
device with 16-bit bus execution is used. These pins
can be configured as I/O pins by setting WM bits in the
MEMCON register to any value other than ’01’.
Note 1: On Power-on Reset, PORTF
RF2:RF0 default to A/D inputs.
CLRF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
PORTF
LATF
0Fh
ADCON1
0CFh
TRISF
•
•
; Program chip select to activate CS1
; for all address less than 03FFFFh,
; while activate CS2 for rests of the
; addresses
; CSEL2 register is secured register.
; Before it can be modified it,
; combination lock must be opened
MOVLW 20h
; Preload WREG with
; correct CSEL2 valu
BCF INTCON, GIE
; Disable interrupts
CALL UNLOCK
; Now unlock it
; Lock is open. Modify CSEL2...
MOVWF CSEL2
; Lock is closed
BSF INTCON, GIE
; Re-enable interrupts
; Chip select is programmed.
•
•
UNLOCK
BSF PSPCON, CMLK1
BSF PSPCON, CMLK0
RETURN
•
•
FIGURE 9-11:
RD LATF
Data Bus
D
Q
VDD
WR LATF
or
WR PORTF
CK
Q
P
Data Latch
D
Q
CK
Q
N
I/O pin
INITIALIZING PORTF
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTF by
clearing output
data latches
Alternate method
to clear output
data latches
Set PORTF as digital I/O
Value used to
initialize data
direction
Set RF3:RF0 as inputs
RF5:RF4 as outputs
RF7:RF6 as inputs
WR TRISF
VSS
Analog
Input
Mode
TRIS Latch
ST
Input
Buffer
RD TRISF
Q
D
EN
RD PORTF
To A/D Converter
Note:
DS39541A-page 116
RF2:RF0 PINS BLOCK
DIAGRAM
pins
2: On Power-on Reset, PORTF pins
RF7:RF3 for PIC18C801 and pins
RF7:RF5, RF3 for PIC18C601, default to
system bus signals.
EXAMPLE 9-6:
PROGRAMMING CHIP
SELECT SIGNALS
Advance Information
I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 9-12:
RF5:RF3 PINS BLOCK DIAGRAM
Q
D
ENEN
RD PORTF
RD LATF
Data Bus
WR LATF
or
PORTF
D
Data
CK
1
Q
CK
RD TRISF
CS Out
System Bus
Control
I/O pin(1)
0
Data Latch
TRIS Latch
D
WR TRISF
Port
Q
External Enable
Drive System
Note 1: I/O pins have diode protection to VDD and VSS.
FIGURE 9-13:
RF7:RF6 PINS BLOCK DIAGRAM
Q
D
ENEN
RD PORTF
RD LATF
Data Bus
D
Q
Port
Data
WR LATF
or
PORTF
UB/LB Out
1
CK
Data Latch
TRIS Latch
D
WR TRISF
I/O pin(1)
0
Q
CK
RD TRISF
System Bus
Control WM = ’01’
Drive System
Note 1: I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 117
PIC18C601/801
TABLE 9-11:
PORTF FUNCTIONS
Name
Bit#
Buffer Type
RF0/AN5
bit0
ST
RF1/AN6
bit1
ST
RF2/AN7
bit2
ST
RF3/CSIO
bit3
ST
RF4/A16/CS2(1)
bit4
ST
RF5/CS1
bit5
ST
RF6/LB
bit6
ST
RF7/UB
bit7
ST
Legend: ST = Schmitt Trigger input
Function
Input/output port pin or analog input
Input/output port pin or analog input
Input/output port pin or analog input
Input/output port pin or I/O chip select
Input/output port pin or chip select 2 or address bit 16
Input/output port pin or chip select 1
Input/output port pin or low byte select signal for external memory
Input/output port pin or high byte select signal for external memory
Note 1: CS2 is available only on PIC18C801.
TABLE 9-12:
Name
SUMMARY OF REGISTERS ASSOCIATED WITH PORTF
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on:
POR,
BOR
Value on all
other
RESETS
TRISF
PORTF Data Direction Control Register
1111 1111
1111 1111
PORTF
Read PORTF pin/Write PORTF Data Latch
xxxx xxxx
uuuu uuuu
Read PORTF Data Latch/Write PORTF Data Latch
0000 0000
uuuu uuuu
VCFG1 VCFG0 PCFG3 PCFG2 PCFG1 PCFG0
--00 0000
--00 0000
WAIT1 WAIT0
0000 --00
0000 --00
LATF
ADCON1
—
—
MEMCON
EBDIS
PGRM
—
—
WM1
WM0
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTF.
DS39541A-page 118
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
9.7
FIGURE 9-14:
PORTG, LATG, and TRISG
Registers
PORTG is a 5-bit wide, bi-directional port. The corresponding data direction register is TRISG. Setting a
TRISG bit (= 1) will make the corresponding PORTG
pin an input (i.e., put the corresponding output driver in
a Hi-Impedance mode). Clearing a TRISG bit (= 0) will
make the corresponding PORTG pin an output (i.e., put
the contents of the output latch on the selected pin).
Read-modify-write operations on the LATG register
read and write the latched output value for PORTG.
PORTG is multiplexed with system bus control signals
ALE, OE, WRH, WRL and BA0. The WRH signal is the
only signal that is disabled and configured as a port pin
(RG3) during external program execution in 8-bit mode.
All other pins are by default, system bus control signals. PORTG can be configured as an I/O port by setting EBDIS bit in the MEMCON register and when
execution is taking place in internal program RAM.
Note:
RD LATG
Data
Bus
WR LATG
or
PORTG
PORTG BLOCK DIAGRAM
IN I/O MODE
D
Q
I/O pin(1)
CK
Data Latch
D
WR TRISG
Q
Schmitt
Trigger
Input
Buffer
CK
TRIS Latch
RD TRISG
Q
On Power-on Reset, PORTG defaults to
system bus signals.
D
EN
EN
RD PORTG
EXAMPLE 9-8:
CLRF
PORTG
CLRF
LATG
MOVLW
04h
MOVWF
TRISG
INITIALIZING PORTG
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTG by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RG1:RG0 as outputs
RG2 as input
RG4:RG3 as outputs
 2001 Microchip Technology Inc.
Note 1: I/O pins have diode protection to VDD and VSS.
Advance Information
DS39541A-page 119
PIC18C601/801
FIGURE 9-15:
PORTG BLOCK DIAGRAM IN SYSTEM BUS MODE
Q
D
ENEN
RD PORTG
RD LATG
Data Bus
D
Q
Data
WR LATG
or
PORTG
I/O pin(1)
Port 0
1
CK
Data Latch
D
WR TRISG
Q
CK
TRIS Latch
RD TRISG
Control Out
System Bus
Control
External Enable
Drive System
Note 1: I/O pins have diode protection to VDD and VSS.
TABLE 9-13:
Name
PORTG FUNCTIONS
Bit#
Buffer Type
RG0/ALE
bit0
ST
RG1/OE
bit1
ST
RG2/WRL
bit2
ST
RG3/WRH
bit3
ST
RG4/BA0
bit4
ST
Legend: ST = Schmitt Trigger input
TABLE 9-14:
Name
Function
Input/output port pin or Address Latch Enable signal for external memory
Input/output port pin or Output Enable signal for external memory
Input/output port pin or Write Low byte signal for external memory
Input/output port pin or Write High byte signal for external memory
Input/output port pin or Byte Address 0 signal for external memory
SUMMARY OF REGISTERS ASSOCIATED WITH PORTG
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on:
POR,
BOR
Value on all
other
RESETS
TRISG
PORTG Data Direction Control Register
---1 1111
---1 1111
PORTG
Read PORTG pin/Write PORTG Data Latch
---x xxxx
---u uuuu
Read PORTG Data Latch/Write PORTG Data Latch
---x xxxx
---u uuuu
0000 --00
0000 --00
LATG
MEMCON
EBDIS
PGRM
WAIT1
WAIT0
—
—
WM1 WM0
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTG.
DS39541A-page 120
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
9.8
Note:
FIGURE 9-16:
PORTH, LATH, and TRISH
Registers
RH3:RH0 PINS BLOCK
DIAGRAM IN I/O MODE
PORTH is available only on PIC18C801
devices.
PORTH is an 8-bit wide, bi-directional I/O port. The corresponding data direction register is TRISH. Setting a
TRISH bit (= 1) will make the corresponding PORTH
pin an input (i.e., put the corresponding output driver in
a Hi-Impedance mode). Clearing a TRISH bit (= 0) will
make the corresponding PORTH pin an output (i.e., put
the contents of the output latch on the selected pin).
Read-modify-write operations on the LATH register
read and write the latched output value for PORTH.
RD LATH
Data
Bus
WR LATH
or
PORTH
D
Q
I/O pin(1)
CK
Data Latch
D
WR TRISH
Q
Schmitt
Trigger
Input
Buffer
CK
TRIS Latch
Pins RH7:RH4 are multiplexed with analog inputs
AN18:AN11, while pins RH3:RH0 are multiplexed with
system address bus A19:A16. By default, pins
RH7:RH4 will setup as A/D inputs and pins RH3:RH0
will setup as system address bus. Register ADCON1
configures RH7:RH4 as I/O or A/D inputs. Register
MEMCON configures RH3:RH0 as I/O or system bus
pins.
RD TRISH
Q
D
EN
EN
RD PORTH
Note 1: On Power-on Reset, PORTH pins
RH7:RH4 default to A/D inputs and read
as ’0’.
2: On Power-on Reset, PORTH pins
RH3:RH0 default to system bus signals.
EXAMPLE 9-9:
CLRF
CLRF
PORTH
LATH
MOVLW
MOVWF
MOVLW
0Fh
ADCON1
0CFh
MOVWF
TRISH
Note 1: I/O pins have diode protection to VDD and VSS.
FIGURE 9-17:
RH7:RH4 PINS BLOCK
DIAGRAM
INITIALIZING PORTH
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTH by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RH3:RH0 as inputs
RH5:RH4 as outputs
RH7:RH6 as inputs
RD LATH
Data
Bus
WR LATH
or
PORTH
D
Q
I/O pin(1)
CK
Data Latch
D
WR TRISH
Q
Schmitt
Trigger
Input
Buffer
CK
TRIS Latch
RD TRISH
Q
D
EN
EN
RD PORTH
To A/D Converter
Note 1: I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 121
PIC18C601/801
FIGURE 9-18:
RH3:RH0 PINS BLOCK DIAGRAM IN SYSTEM BUS MODE
Q
D
ENEN
RD PORTH
RD LATD
Data Bus
WR LATH
or
PORTH
D
Q
Port 0
Data 1
CK
Data Latch
D
WR TRISH
Q
CK
TRIS Latch
External Enable.
System Bus
Control
I/O pin(1)
TTL
Input
Buffer
RD TRISH
Address Out
Drive System
To Instruction Register
Instruction Read
Note 1: I/O pins have diode protection to VDD and VSS.
DS39541A-page 122
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 9-15:
PORTH FUNCTIONS
Name
Bit#
Buffer Type
Function
RH0/A16(1)
bit0
ST
Input/output port pin or Address bit 16 for external memory interface
bit1
ST
Input/output port pin or Address bit 17 for external memory interface
RH2/A18(1)
bit2
ST
Input/output port pin or Address bit 18 for external memory interface
RH3/A19(1)
bit3
ST
Input/output port pin or Address bit 19 for external memory interface
RH4/AN8(1)
bit4
ST
Input/output port pin or analog input channel 8
(1)
RH5/AN9
bit5
ST
Input/output port pin or analog input channel 9
RH6/AN10(1)
bit6
ST
Input/output port pin or analog input channel 10
RH7/AN11(1)
bit7
ST
Input/output port pin or analog input channel 11
Legend: ST = Schmitt Trigger input
Note 1: PORTH is available only on PIC18C801 devices.
RH1/A17(1)
TABLE 9-16:
Name
SUMMARY OF REGISTERS ASSOCIATED WITH PORTH
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on:
POR,
BOR
Value on all
other
RESETS
TRISH
PORTH Data Direction Control Register
1111 1111
1111 1111
PORTH
Read PORTH pin/Write PORTH Data Latch
xxxx xxxx
uuuu uuuu
Read PORTH Data Latch/Write PORTH Data Latch
LATH
ADCON1
—
—
MEMCON
EBDIS
PGRM
xxxx xxxx
uuuu uuuu
VCFG1 VCFG0 PCFG3 PCFG2 PCFG1 PCFG0
--00 0000
--00 0000
WAIT1
0000 --00
0000 --00
WAIT0
—
—
WM1
WM0
Legend: x = unknown, u = unchanged, - = unimplemented. Shaded cells are not used by PORTH.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 123
PIC18C601/801
9.9
Note:
FIGURE 9-19:
PORTJ, LATJ, and TRISJ
Registers
PORTJ is available only on PIC18C801
devices.
PORTJ is an 8-bit wide, bi-directional I/O port. The corresponding data direction register is TRISJ. Setting a
TRISJ bit (= 1) will make the corresponding PORTJ pin
an input (i.e., put the corresponding output driver in a
Hi-Impedance mode). Clearing a TRISJ bit (= 0) will
make the corresponding PORTJ pin an output (i.e., put
the contents of the output latch on the selected pin).
Read-modify-write operations on the LATJ register
read and write the latched output value for PORTJ.
RD LATJ
Data
Bus
WR LATJ
or
PORTJ
D
Q
I/O pin(1)
CK
Data Latch
D
WR TRISJ
Q
Schmitt
Trigger
Input
Buffer
CK
TRIS Latch
PORTJ is multiplexed with de-multiplexed system data
bus D7:D0, when device is configured in 8-bit execution
mode. Register MEMCON configures PORTJ as I/O or
system bus pins.
Note:
PORTJ BLOCK DIAGRAM
IN I/O MODE
RD TRISJ
On Power-on Reset, PORTJ defaults to
system bus signals.
Q
D
EN
EN
RD PORTJ
EXAMPLE 9-10:
CLRF
PORTJ
CLRF
LATJ
MOVLW
0CFh
MOVWF
TRISJ
DS39541A-page 124
INITIALIZING PORTJ
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTJ by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RJ3:RJ0 as inputs
RJ5:RJ4 as outputs
RJ7:RJ6 as inputs
Note 1: I/O pins have diode protection to VDD and VSS.
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 9-20:
PORTJ BLOCK DIAGRAM IN SYSTEM DATA BUS MODE
Q
D
ENEN
RD PORTJ
RD LATD
Data Bus
WR LATJ
or
PORTJ
D
Q
Port
I/O pin(1)
0
Data 1
CK
Data Latch
TRIS Latch
WR TRISJ
External Enable
System Bus
Control
D
Q
CK
S
R
TTL
Input
Buffer
RD TRISJ
Data Out
Drive System
To Instruction Register
Instruction Read
Note 1: I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 125
PIC18C601/801
TABLE 9-17:
PORTJ FUNCTIONS
Name
Bit#
Buffer Type
Function
RJ0/D0(1)
bit0
ST/TTL
Input/output port pin
bit1
ST/TTL
Input/output port pin
RJ2/D2(1)
bit2
ST/TTL
Input/output port pin
RJ3/D3(1)
bit3
ST/TTL
Input/output port pin
RJ4/D4(1)
bit4
ST/TTL
Input/output port pin
(1)
RJ5/D5
bit5
ST/TTL
Input/output port pin
RJ6/D6(1)
bit6
ST/TTL
Input/output port pin
RJ7/D7(1)
bit7
ST/TTL
Input/output port pin
Legend: ST = Schmitt Trigger input, TTL = TTL input
Note 1: PORTJ is available only on PIC18C801 devices.
RJ1/D1(1)
TABLE 9-18:
Name
or Data bit 0 for external memory interface
or Data bit 1 for external memory interface
or Data bit 2 for external memory interface
or Data bit 3 for external memory interface
or Data bit 4 for external memory interface
or Data bit 5 for external memory interface
or Data bit 6 for external memory interface
or Data bit 7 for external memory interface
SUMMARY OF REGISTERS ASSOCIATED WITH PORTJ
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on:
POR,
BOR
Value on all
other
RESETS
TRISJ
PORTJ Data Direction Control Register
1111 1111
1111 1111
PORTJ
Read PORTJ pin/Write PORTJ Data Latch
xxxx xxxx
uuuu uuuu
xxxx xxxx
uuuu uuuu
0000 --00
0000 --00
LATJ
MEMCON
Read PORTJ Data Latch/Write PORTJ Data Latch
EBDIS PGRM WAIT1 WAIT0
—
—
WM1
WM0
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTJ.
DS39541A-page 126
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
10.0
TIMER0 MODULE
Register 10-1 shows the Timer0 Control register
(T0CON).
The Timer0 module has the following features:
• Software selectable as an 8-bit or 16-bit timer/
counter
• Readable and writable
• Dedicated 8-bit software programmable prescaler
• Clock source selectable to be external or internal
• Interrupt on overflow from FFh to 00h in 8-bit
mode and FFFFh to 0000h in 16-bit mode
• Edge select for external clock
REGISTER 10-1:
Figure 10-1 shows a simplified block diagram of the
Timer0 module in 8-bit mode and Figure 10-2 shows a
simplified block diagram of the Timer0 module in 16-bit
mode.
The T0CON register is a readable and writable register
that controls all the aspects of Timer0, including the
prescale selection.
Note:
Timer0 is enabled on POR.
T0CON REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
TMR0ON
T08BIT
T0CS
T0SE
PSA
T0PS2
T0PS1
T0PS0
bit 7
bit 0
bit 7
TMR0ON: Timer0 On/Off Control bit
1 = Enables Timer0
0 = Stops Timer0
bit 6
T08BIT: Timer0 8-bit/16-bit Control bit
1 = Timer0 is configured as an 8-bit timer/counter
0 = Timer0 is configured as a 16-bit timer/counter
bit 5
T0CS: Timer0 Clock Source Select bit
1 = Transition on T0CKI pin
0 = Internal instruction cycle clock (CLKOUT)
bit 4
T0SE: Timer0 Source Edge Select bit
1 = Increment on high-to-low transition on T0CKI pin
0 = Increment on low-to-high transition on T0CKI pin
bit 3
PSA: Timer0 Prescaler Assignment bit
1 = TImer0 prescaler is NOT assigned. Timer0 clock input bypasses prescaler.
0 = Timer0 prescaler is assigned. Timer0 clock input comes from prescaler output.
bit 2-0
T0PS2:T0PS0: Timer0 Prescaler Select bits
111 = 1:256 prescale value
110 = 1:128 prescale value
101 = 1:64 prescale value
100 = 1:32 prescale value
011 = 1:16 prescale value
010 = 1:8 prescale value
001 = 1:4 prescale value
000 = 1:2 prescale value
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 127
PIC18C601/801
FIGURE 10-1:
TIMER0 BLOCK DIAGRAM IN 8-BIT MODE
Data Bus
FOSC/4
0
8
0
1
RA4/T0CKI
pin(2)
Programmable
Prescaler
1
Sync with
Internal
Clocks
TMR0L
(2 TCY delay)
T0SE
3
PSA
Set Interrupt
Flag bit TMR0IF
on Overflow
T0PS2, T0PS1, T0PS0
T0CS(1)
Note 1: Upon RESET, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
2: I/O pins have diode protection to VDD and VSS.
FIGURE 10-2:
FOSC/4
TIMER0 BLOCK DIAGRAM IN 16-BIT MODE
0
0
1
Programmable
Prescaler
RA4/T0CKI
pin(2)
T0SE
1
Sync with
Internal
Clocks
TMR0L
TMR0
High Byte
8
(2 TCY delay)
3
Read TMR0L
T0PS2, T0PS1, T0PS0
T0CS(1)
Set Interrupt
Flag bit TMR0IF
on Overflow
Write TMR0L
PSA
8
8
TMR0H
8
Data Bus<7:0>
Note 1: Upon RESET, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
2: I/O pins have diode protection to VDD and VSS.
DS39541A-page 128
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
10.1
10.2.1
Timer0 Operation
SWITCHING PRESCALER
ASSIGNMENT
Timer0 can operate as a timer or as a counter.
The prescaler assignment is fully under software control (i.e., it can be changed “on-the-fly” during program
execution).
Timer mode is selected by clearing the T0CS bit. In
Timer mode, the Timer0 module will increment every
instruction cycle (without prescaler). If the TMR0L register is written, the increment is inhibited for the following two instruction cycles. The user can work around
this by writing an adjusted value to the TMR0L register.
10.3
The TMR0 interrupt is generated when the TMR0 register overflows from FFh to 00h in 8-bit mode, or FFFFh
to 0000h in 16-bit mode. This overflow sets the TMR0IF
bit. The interrupt can be masked by clearing the
TMR0IE bit. The TMR0IF bit must be cleared in software by the Timer0 module Interrupt Service Routine
before re-enabling this interrupt. The TMR0 interrupt
cannot awaken the processor from SLEEP, since the
timer is shut-off during SLEEP.
Counter mode is selected by setting the T0CS bit. In
Counter mode, Timer0 will increment either on every
rising, or falling edge, of pin RA4/T0CKI. The incrementing edge is determined by the Timer0 Source
Edge Select bit (T0SE). Clearing the T0SE bit selects
the rising edge. Restrictions on the external clock input
are discussed below.
When an external clock input is used for Timer0, it must
meet certain requirements. The requirements ensure
the external clock can be synchronized with the internal
phase clock (TOSC). Also, there is a delay in the actual
incrementing of Timer0 after synchronization.
10.2
10.4
An 8-bit counter is available as a prescaler for the
Timer0 module. The prescaler is not readable or
writable.
TMR0H is not the high byte of the timer/counter in
16-bit mode, but is actually a buffered version of the
high byte of Timer0 (refer to Figure 10-1). The high byte
of the Timer0 counter/timer is not directly readable nor
writable. TMR0H is updated with the contents of the
high byte of Timer0 during a read of TMR0L. This provides the ability to read all 16-bits of Timer0 without
having to verify that the read of the high and low byte
were valid, due to a rollover between successive reads
of the high and low byte.
The PSA and T0PS2:T0PS0 bits determine the
prescaler assignment and prescale ratio.
Clearing bit PSA will assign the prescaler to the Timer0
module. When the prescaler is assigned to the Timer0
module, prescale values of 1:2, 1:4, ..., 1:256 are
selectable.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g. CLRF TMR0,
MOVWF TMR0, BSF TMR0, x.... etc.) will clear the
prescaler count.
Name
A write to the high byte of Timer0 must also take place
through the TMR0H buffer register. Timer0 high byte is
updated with the contents of the buffered value of
TMR0H, when a write occurs to TMR0L. This allows all
16-bits of Timer0 to be updated at once.
Writing to TMR0 when the prescaler is
assigned to Timer0, will clear the prescaler
count but will not change the prescaler
assignment.
TABLE 10-1:
16-Bit Mode Timer Reads and
Writes
Timer0 can be set in 16-bit mode by clearing T0CON
T08BIT. Registers TMR0H and TMR0L are used to
access 16-bit timer value.
Prescaler
Note:
Timer0 Interrupt
REGISTERS ASSOCIATED WITH TIMER0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
RESETS
TMR0L
Timer0 Module’s Low Byte Register
xxxx xxxx
uuuu uuuu
TMR0H
Timer0 Module’s High Byte Register
0000 0000
0000 0000
INTCON
GIE/GIEH
TMR0ON
RBIF 0000 000x
T0PS1 T0PS0 1111 1111
0000 000u
T0CON
TRISA
—
--11 1111
--11 1111
PEIE/GIEL TMR0IE INT0IE
T08BIT
T0CS
T0SE
RBIE
TMR0IF INT0IF
PSA
T0PS2
PORTA Data Direction Register
1111 1111
Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by Timer0.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 129
PIC18C601/801
11.0
TIMER1 MODULE
Register 11-1 shows the Timer1 Control register. This
register controls the operating mode of the Timer1
module as well as contains the Timer1 oscillator enable
bit (T1OSCEN). Timer1 can be enabled/disabled by
setting/clearing control bit TMR1ON (T1CON register).
The Timer1 module timer/counter has the following
features:
• 16-bit timer/counter
(Two 8-bit registers: TMR1H and TMR1L)
• Readable and writable (both registers)
• Internal or external clock select
• Interrupt on overflow from FFFFh to 0000h
• RESET from CCP module special event trigger
REGISTER 11-1:
Figure 11-1 is a simplified block diagram of the Timer1
module.
Note:
Timer1 is disabled on POR.
T1CON REGISTER
R/W-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
RD16
—
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
bit 7
bit 0
bit 7
RD16: 16-bit Read/Write Mode Enable bit
1 = Enables register Read/Write of TImer1 in one 16-bit operation
0 = Enables register Read/Write of Timer1 in two 8-bit operations
bit 6
Unimplemented: Read as '0'
bit 5-4
T1CKPS1:T1CKPS0: Timer1 Input Clock Prescale Select bits
11 = 1:8 Prescale value
10 = 1:4 Prescale value
01 = 1:2 Prescale value
00 = 1:1 Prescale value
bit 3
T1OSCEN: Timer1 Oscillator Enable bit
1 = Timer1 Oscillator is enabled
0 = Timer1 Oscillator is shut-off
The oscillator inverter and feedback resistor are turned off to eliminate power drain.
bit 2
T1SYNC: Timer1 External Clock Input Synchronization Select bit
When TMR1CS = 1:
1 = Do not synchronize external clock input
0 = Synchronize external clock input
When TMR1CS = 0:
This bit is ignored. Timer1 uses the internal clock when TMR1CS = 0.
bit 1
TMR1CS: Timer1 Clock Source Select bit
1 = External clock from pin RC0/T1OSO/T13CKI (on the rising edge)
0 = Internal clock (FOSC/4)
bit 0
TMR1ON: Timer1 On bit
1 = Enables Timer1
0 = Stops Timer1
Legend:
DS39541A-page 130
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
11.1
Timer1 Operation
When TMR1CS is clear, Timer1 increments every
instruction cycle. When TMR1CS is set, Timer1 increments on every rising edge of the external clock input
or the Timer1 oscillator, if enabled.
Timer1 can operate in one of these modes:
• As a timer
• As a synchronous counter
• As an asynchronous counter
When the Timer1 oscillator is enabled (T1OSCEN is set),
the RC1/T1OSI and RC0/T1OSO/T1CKI pins become
inputs. That is, the TRISC<1:0> value is ignored.
The operating mode is determined by the clock select
bit, TMR1CS (T1CON register).
Note:
Timer1 also has an internal “RESET input”. This RESET
can be generated by the CCP module (Table 14.0).
When Timer1 is configured in an Asynchronous mode, care must be taken to
make sure that there is no incoming pulse
while Timer1 is being turned off. If there is
an incoming pulse while Timer1 is being
turned off, Timer1 value may become
unpredictable.
If an application requires that Timer1 be
turned off and if it is possible that Timer1
may receive an incoming pulse while being
turned off, synchronize the external clock
first, by clearing the T1SYNC bit of register
T1CON. Please note that this may cause
Timer1 to miss up to one count.
FIGURE 11-1:
TIMER1 BLOCK DIAGRAM
CCP Special Event Trigger
TMR1IF
Overflow
Interrupt
Flag Bit
TMR1
TMR1H
0
CLR
TMR1L
1
TMR1ON
On/Off
T1SYNC
T1OSC
T13CKI/T1OSO
T1OSI
T1OSCEN
Enable
Oscillator(1)
1
FOSC/4
Internal
Clock
Synchronized
Clock Input
Prescaler
1, 2, 4, 8
Synchronize
det
0
2
T1CKPS1:T1CKPS0
SLEEP Input
TMR1CS
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This reduces power drain.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 131
PIC18C601/801
FIGURE 11-2:
TIMER1 BLOCK DIAGRAM: 16-BIT READ/WRITE MODE
Data Bus<7:0>
8
TMR1H
8
8
Write TMR1L
Special Event Trigger
Read TMR1L
TMR1IF
Overflow
Interrupt
Flag bit
Timer 1
High Byte
Synchronized
Clock Input
0
TMR1
8
TMR1L
1
TMR1ON
On/Off
T1SYNC
T1OSC
T13CKI/T1OSO
T1OSI
1
T1OSCEN
Enable
Oscillator(1)
FOSC/4
Internal
Clock
Synchronize
Prescaler
1, 2, 4, 8
det
0
2
SLEEP Input
TMR1CS
T1CKPS1:T1CKPS0
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This reduces power drain.
DS39541A-page 132
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
11.2
Timer1 Oscillator
11.4
A crystal oscillator circuit is built-in between pins T1OSI
(input) and T1OSO (amplifier output). It is enabled by
setting control bit T1OSCEN (T1CON register). The
oscillator is a low power oscillator rated up to 200 kHz.
It will continue to run during SLEEP. It is primarily
intended for a 32 kHz crystal. Table 11-1 shows the
capacitor selection for the Timer1 oscillator.
The user must provide a software time delay to ensure
proper start-up of the Timer1 oscillator.
Resetting Timer1 using a CCP
Trigger Output
If the CCP module is configured in Compare mode
to
generate
a
“special
event
trigger"
(CCP1M3:CCP1M0 = 1011), this signal will reset
Timer1 and start an A/D conversion (if the A/D module
is enabled).
Note:
The special event triggers from the CCP1
module will not set interrupt flag bit
TMR1IF (PIR registers).
CAPACITOR SELECTION FOR
THE ALTERNATE
OSCILLATOR
Timer1 must be configured for either Timer, or Synchronized Counter mode, to take advantage of this feature.
If Timer1 is running in Asynchronous Counter mode,
this RESET operation may not work.
Osc Type
Freq
C1
C2
LP
32 kHz
TBD(1)
TBD(1)
In the event that a write to Timer1 coincides with a special
event trigger from CCP1, the write will take precedence.
TABLE 11-1:
Crystal to be Tested:
32.768 kHz Epson C-001R32.768K-A ± 20 PPM
Note 1: Microchip suggests 33 pF as a starting
point in validating the oscillator circuit.
2: Higher capacitance increases the stability
of the oscillator, but also increases the
start-up time.
3: Since each resonator/crystal has its own
characteristics, the user should consult the
resonator/crystal manufacturer for appropriate values of external components.
4: Capacitor values are for design guidance
only.
11.3
Timer1 Interrupt
The TMR1 Register pair (TMR1H:TMR1L) increments
from 0000h to FFFFh and rolls over to 0000h. The
TMR1 interrupt, if enabled, is generated on overflow,
which is latched in interrupt flag bit TMR1IF (PIR registers). This interrupt can be enabled/disabled by setting/
clearing TMR1 interrupt enable bit TMR1IE (PIE
registers).
 2001 Microchip Technology Inc.
In this mode of operation, the CCPR1H:CCPR1L registers pair, effectively becomes the period register for
Timer1.
11.5
Timer1 16-Bit Read/Write Mode
Timer1 can be configured for 16-bit reads and writes
(see Figure 11-2). When the RD16 control bit (T1CON
register) is set, the address for TMR1H is mapped to a
buffer register for the high byte of Timer1. A read from
TMR1L will load the contents of the high byte of Timer1
into the Timer1 high byte buffer. This provides the user
with the ability to accurately read all 16 bits of Timer1,
without having to determine whether a read of the high
byte followed by a read of the low byte is valid, due to
a rollover between reads.
A write to the high byte of Timer1 must also take place
through the TMR1H buffer register. Timer1 high byte is
updated with the contents of TMR1H when a write
occurs to TMR1L. This allows a user to write all 16-bits
to both the high and low bytes of Timer1 at once.
The high byte of Timer1 is not directly readable or writable in this mode. All reads and writes must take place
through the Timer1 high byte buffer register. Writes to
TMR1H do not clear the Timer1 prescaler. The
prescaler is only cleared on writes to TMR1L.
Advance Information
DS39541A-page 133
PIC18C601/801
TABLE 11-2:
REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
INTCON
GIE/
GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x 0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000 -000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000 -000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000 -000 0000
TMR1L
Holding register for the Least Significant Byte of the 16-bit TMR1 register
TMR1H
Holding register for the Most Significant Byte of the 16-bit TMR1 register
T1CON
Legend:
RD16
—
T1CKPS1
T1CKPS0
T1OSCEN T1SYNC TMR1CS
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
TMR1ON
0-00 0000 u-uu uuuu
x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the Timer1 module.
DS39541A-page 134
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
12.0
TIMER2 MODULE
12.1
The Timer2 module timer has the following features:
•
•
•
•
•
•
•
8-bit timer (TMR2 register)
8-bit period register (PR2)
Readable and writable (both registers)
Software programmable prescaler (1:1, 1:4, 1:16)
Software programmable postscaler (1:1 to 1:16)
Interrupt on TMR2 match of PR2
SSP module optional use of TMR2 output to
generate clock shift
Register 12-1 shows the Timer2 Control register.
Timer2 can be shut-off by clearing control bit TMR2ON
(T2CON register), to minimize power consumption.
Figure 12-1 is a simplified block diagram of the Timer2
module. The prescaler and postscaler selection of
Timer2 are controlled by this register.
Timer2 Operation
Timer2 can be used as the PWM time-base for the PWM
mode of the CCP module. The TMR2 register is readable and writable, and is cleared on any device RESET.
The input clock (FOSC/4) has a prescale option of 1:1,
1:4,
or
1:16,
selected
by
control
bits
T2CKPS1:T2CKPS0 (T2CON register). The match output of TMR2 goes through a 4-bit postscaler (which
gives a 1:1 to 1:16 scaling inclusive) to generate a TMR2
interrupt (latched in flag bit TMR2IF, PIR registers).
The prescaler and postscaler counters are cleared
when any of the following occurs:
• A write to the TMR2 register
• A write to the T2CON register
• Any device RESET (Power-on Reset, MCLR
Reset, or Watchdog Timer Reset)
TMR2 is not cleared when T2CON is written.
Note:
REGISTER 12-1:
Timer2 is disabled on POR.
T2CON REGISTER
U-0
—
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0
bit 7
bit 0
bit 7
Unimplemented: Read as '0'
bit 6-3
TOUTPS3:TOUTPS0: Timer2 Output Postscale Select bits
0000 = 1:1 Postscale
0001 = 1:2 Postscale
•
•
•
1111 = 1:16 Postscale
bit 2
TMR2ON: Timer2 On bit
1 = Timer2 is on
0 = Timer2 is off
bit 1-0
T2CKPS1:T2CKPS0: Timer2 Clock Prescale Select bits
00 = Prescaler is 1
01 = Prescaler is 4
1x = Prescaler is 16
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 135
PIC18C601/801
12.2
Timer2 Interrupt
12.3
The Timer2 module has an 8-bit period register, PR2.
Timer2 increments from 00h until it matches PR2 and
then resets to 00h on the next increment cycle. PR2 is
a readable and writable register. The PR2 register is
initialized to FFh upon RESET.
FIGURE 12-1:
Output of TMR2
The output of TMR2 (before the postscaler) is a clock
input to the Synchronous Serial Port module, which
optionally uses it to generate the shift clock.
TIMER2 BLOCK DIAGRAM
Sets Flag
bit TMR2IF
TMR2
Output(1)
Prescaler
FOSC/4
TMR2
1:1, 1:4, 1:16
2
RESET
Postscaler
Comparator
EQ
1:1 to 1:16
T2CKPS1:T2CKPS0
4
PR2
TOUTPS3:TOUTPS0
Note 1: TMR2 register output can be software selected by the SSP Module as a baud clock.
TABLE 12-1:
REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
INTCON
GIE/
GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x 0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000 -000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000 -000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000 -000 0000
TMR2
T2CON
PR2
Timer2 Module’s Register
—
0000 0000 0000 0000
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON
Timer2 Period Register
T2CKPS1 T2CKPS0 -000 0000 -000 0000
1111 1111 1111 1111
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the Timer2 module.
DS39541A-page 136
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
13.0
TIMER3 MODULE
Figure 13-1 is a simplified block diagram of the Timer3
module.
The Timer3 module timer/counter has the following
features:
• 16-bit timer/counter
(Two 8-bit registers: TMR3H and TMR3L)
• Readable and writable (both registers)
• Internal or external clock select
• Interrupt on overflow from FFFFh to 0000h
• RESET from CCP module trigger
Register 13-1 shows the Timer3 Control register. This
register controls the operating mode of the Timer3
module and sets the CCP clock source.
Register 11-1 shows the Timer1 Control register. This
register controls the operating mode of the Timer1
module, as well as contains the Timer1 oscillator
enable bit (T1OSCEN), which can be a clock source for
Timer3.
Note:
REGISTER 13-1:
Timer3 is disabled on POR.
T3CON REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
RD16
T3CCP2
T3CKPS1
T3CKPS0
T3CCP1
T3SYNC
TMR3CS
TMR3ON
bit 7
bit 0
bit 7
RD16: 16-bit Read/Write Mode Enable
1 = Enables register Read/Write of Timer3 in one 16-bit operation
0 = Enables register Read/Write of Timer3 in two 8-bit operations
bit 6,3
T3CCP2:T3CCP1: Timer3 and Timer1 to CCPx Enable bits
1x = Timer3 is the clock source for compare/capture CCP modules
01 = Timer3 is the clock source for compare/capture of CCP2,
Timer1 is the clock source for compare/capture of CCP1
00 = Timer1 is the clock source for compare/capture CCP modules
bit 5-4
T3CKPS1:T3CKPS0: Timer3 Input Clock Prescale Select bits
11 = 1:8 Prescale value
10 = 1:4 Prescale value
01 = 1:2 Prescale value
00 = 1:1 Prescale value
bit 2
T3SYNC: Timer3 External Clock Input Synchronization Control bit
(Not usable if the system clock comes from Timer1/Timer3)
When TMR3CS = 1:
1 = Do not synchronize external clock input
0 = Synchronize external clock input
When TMR3CS = 0:
This bit is ignored. Timer3 uses the internal clock when TMR3CS = 0.
bit 1
TMR3CS: Timer3 Clock Source Select bit
1 = External clock input from Timer1 oscillator or T1CKI (on the rising edge after the first
falling edge)
0 = Internal clock (FOSC/4)
bit 0
TMR3ON: Timer3 On bit
1 = Enables Timer3
0 = Stops Timer3
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 137
PIC18C601/801
13.1
Timer3 Operation
When TMR3CS = 0, Timer3 increments every instruction cycle. When TMR3CS = 1, Timer3 increments on
every rising edge of the Timer1 external clock input or
the Timer1 oscillator, if enabled.
Timer3 can operate in one of these modes:
• As a timer
• As a synchronous counter
• As an asynchronous counter
When the Timer1 oscillator is enabled (T1OSCEN is
set), the RC1/T1OSI and RC0/T1OSO/T1CKI pins
become inputs. That is, the TRISC<1:0> value is
ignored.
The operating mode is determined by the clock select
bit, TMR3CS (T3CON register).
Timer3 also has an internal “RESET input”. This
RESET can be generated by the CCP module
(Section 13.0).
FIGURE 13-1:
TIMER3 BLOCK DIAGRAM
CCP Special Trigger
T3CCPx
0
TMR3IF
Overflow
Interrupt
Flag bit
TMR3H
CLR
TMR3L
1
TMR3ON
On/Off
T1OSC
T1OSO/
T13CKI
Synchronized
Clock Input
T3SYNC
(3)
1
T1OSCEN FOSC/4
Enable
Internal
Oscillator(1) Clock
T1OSI
Synchronize
Prescaler
1, 2, 4, 8
det
0
2
SLEEP Input
TMR3CS
T3CKPS1:T3CKPS0
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This reduces power drain.
FIGURE 13-2:
TIMER3 BLOCK DIAGRAM CONFIGURED IN 16-BIT READ/WRITE MODE
Data Bus<7:0>
8
TMR3H
8
8
Write TMR3L
Read TMR3L
TMR3IF Overflow
Interrupt Flag
bit
8
CCP Special Trigger
T3CCPx
0
TMR3
TMR3H
TMR3L
CLR
Synchronized
Clock Input
1
To Timer1 Clock Input
T1OSO/
T13CKI
T1OSI
TMR3ON
On/Off
T1OSC
T3SYNC
1
T1OSCEN
Enable
Oscillator(1)
FOSC/4
Internal
Clock
Prescaler
1, 2, 4, 8
Synchronize
det
0
2
T3CKPS1:T3CKPS0
TMR3CS
SLEEP Input
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This reduces power drain.
DS39541A-page 138
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
13.2
Timer1 Oscillator
13.4
The Timer1 oscillator may be used as the clock source
for Timer3. The Timer1 oscillator is enabled by setting
the T1OSCEN bit (T1CON Register). The oscillator is
a low power oscillator rated up to 200 kHz. Refer to
“Timer1 Module”, Section 11.0, for Timer1 oscillator
details.
13.3
Resetting Timer3 Using a CCP
Trigger Output
If the CCP module is configured in Compare mode to
generate a “special event trigger" (CCP1M3:CCP1M0
= 1011), this signal will reset Timer3.
Note:
The special event triggers from the CCP
module will not set interrupt flag bit
TMR3IF (PIR registers).
Timer3 Interrupt
The TMR3 register pair (TMR3H:TMR3L) increments
from 0000h to FFFFh and rolls over to 0000h. The
TMR3 interrupt, if enabled, is generated on overflow,
which is latched in interrupt flag bit TMR3IF (PIE
registers). This interrupt can be enabled/disabled by
setting/clearing TMR3 interrupt enable bit TMR3IE
(PIE registers).
TABLE 13-1:
Timer3 must be configured for either Timer, or Synchronized Counter mode, to take advantage of this feature. If
Timer3 is running in Asynchronous Counter mode, this
RESET operation may not work. In the event that a write
to Timer3 coincides with a special event trigger from
CCP1, the write will take precedence. In this mode of
operation, the CCPR1H:CCPR1L registers pair
becomes the period register for Timer3. Refer to
Section 14.0, “Capture/Compare/PWM (CCP) Modules”,
for CCP details.
REGISTERS ASSOCIATED WITH TIMER3 AS A TIMER/COUNTER
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on
all other
RESETS
INTCON
GIE/
GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x
0000 000u
PIR2
—
—
—
—
BCLIF
LVDIF
TMR3IF
CCP2IF
---- 0000
-0-- 0000
PIE2
—
—
—
—
BCLIE
LVDIE
TMR3IE
CCP2IE
---- 0000
-0-- 0000
—
—
—
—
BCLIP
LVDIP
TMR3IP
CCP2IP
IPR2
---- 0000
-0-- 0000
TMR3L
Holding register for the Least Significant Byte of the 16-bit TMR3 register
xxxx xxxx
uuuu uuuu
TMR3H
Holding register for the Most Significant Byte of the 16-bit TMR3 register
xxxx xxxx
uuuu uuuu
T1CON
RD16
T1SYNC
TMR1CS TMR1ON 0-00 0000
u-uu uuuu
T3SYNC
TMR3CS TMR3ON 0000 0000
uuuu uuuu
T3CON
Legend:
RD16
—
T1CKPS1 T1CKPS0 T1OSCEN
T3CCP2 T3CKPS1 T3CKPS0
T3CCP1
x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the Timer3 module.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 139
PIC18C601/801
NOTES:
DS39541A-page 140
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
14.0
CAPTURE/COMPARE/PWM
(CCP) MODULES
Each CCP (Capture/Compare/PWM) module contains
a 16-bit register that can operate as a 16-bit capture
register, as a 16-bit compare register, or as a PWM
Duty Cycle register. Table 14-1 shows the timer
resources of the CCP module modes.
REGISTER 14-1:
CCP1CON
The operation of CCP1 is identical to that of CCP2, with
the exception of the special event trigger. Therefore,
operation of a CCP module in the following sections is
described, with respect to CCP1.
Table 14-2 shows the interaction of the CCP modules.
Register 14-1 shows the CCPx Control registers
(CCPxCON). For the CCP1 module, the register is
called CCP1CON and for the CCP2 module, the register is called CCP2CON.
CCP1CON REGISTER
CCP2CON REGISTER
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
DC2B1
DC2B0
CCP2M3
CCP2M2
CCP2M1
CCP2M0
bit 7
CCP2CON
bit 0
bit 7
bit 0
bit 7-6
Unimplemented: Read as '0'
bit 5-4
DCxB1:DCxB0: PWM Duty Cycle bit1 and bit0
Capture mode:
Unused
Compare mode:
Unused
PWM mode:
These bits are the two LSbs (bit1 and bit0) of the 10-bit PWM duty cycle. The upper eight bits
(DCx9:DCx2) of the duty cycle are found in CCPRxL.
bit 3-0
CCPxM3:CCPxM0: CCPx Mode Select bits
0000 = Capture/Compare/PWM off (resets CCPx module)
0001 = Reserved
0010 = Compare mode, toggle output on match (CCPxIF bit is set)
0011 = Reserved
0100 = Capture mode, every falling edge
0101 = Capture mode, every rising edge
0110 = Capture mode, every 4th rising edge
0111 = Capture mode, every 16th rising edge
1000 = Compare mode,
Initialize CCP pin Low, on compare match force CCP pin High (CCPIF bit is set)
1001 = Compare mode,
Initialize CCP pin High, on compare match force CCP pin Low (CCPIF bit is set)
1010 = Compare mode,
Generate software interrupt on compare match
(CCPIF bit is set, CCP pin is unaffected)
1011 = Compare mode,
Trigger special event (CCPIF bit is set, reset TMR1 or TMR3)
11xx = PWM mode
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 141
PIC18C601/801
14.1
CCP1 Module
14.3
Capture/Compare/PWM Register1 (CCPR1) is comprised of two 8-bit registers: CCPR1L (low byte) and
CCPR1H (high byte). The CCP1CON register controls
the operation of CCP1. All are readable and writable.
14.2
CCP2 Module
Capture/Compare/PWM Register2 (CCPR2) is comprised of two 8-bit registers: CCPR2L (low byte) and
CCPR2H (high byte). The CCP2CON register controls
the operation of CCP2. All are readable and writable.
TABLE 14-1:
CCP MODE - TIMER
RESOURCE
CCP Mode
Timer Resource
Capture
Compare
PWM
Timer1 or Timer3
Timer1 or Timer3
Timer2
Capture Mode
In Capture mode, CCPR1H:CCPR1L captures the 16-bit
value of the TMR1 or TMR3 registers, when an event
occurs on pin RC2/CCP1. An event is defined as:
•
•
•
•
every falling edge
every rising edge
every 4th rising edge
every 16th rising edge
An event is selected by control bits CCP1M3:CCP1M0
(CCP1CON<3:0>). When a capture is made, the interrupt request flag bit CCP1IF (PIR registers) is set. It
must be cleared in software. If another capture occurs
before the value in register CCPR1 is read, the old captured value will be lost.
14.3.1
CCP PIN CONFIGURATION
In Capture mode, the RC2/CCP1 pin should be configured as an input by setting the TRISC<2> bit.
Note:
14.3.2
If the RC2/CCP1 is configured as an output, a write to the port can cause a capture
condition.
TIMER1/TIMER3 MODE SELECTION
The timers used with the capture feature (either Timer1
and/or Timer3) must be running in Timer mode or Synchronized Counter mode. In Asynchronous Counter
mode, the capture operation may not work. The timer
used with each CCP module is selected in the T3CON
register.
TABLE 14-2:
INTERACTION OF TWO CCP MODULES
CCPx Mode CCPy Mode
Interaction
Capture
Capture
TMR1 or TMR3 time-base. Time-base can be different for each CCP.
Capture
Compare
The compare could be configured for the special event trigger, which clears either TMR1
or TMR3, depending upon which time-base is used.
Compare
Compare
The compare(s) could be configured for the special event trigger, which clears TMR1 or
TMR3, depending upon which time-base is used.
PWM
PWM
PWM
Capture
None.
PWM
Compare
None.
DS39541A-page 142
The PWMs will have the same frequency and update rate (TMR2 interrupt).
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
14.3.3
SOFTWARE INTERRUPT
Switching from one capture prescaler to another may
generate an interrupt. Also, the prescaler counter will
not be cleared; therefore, the first capture may be from
a non-zero prescaler. Example 14-1 shows the recommended method for switching between capture prescalers. This example also clears the prescaler counter
and will not generate the “false” interrupt.
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep bit
CCP1IE (PIE registers) clear to avoid false interrupts
and should clear the flag bit CCP1IF, following any
such change in operating mode.
14.3.4
CCP PRESCALER
EXAMPLE 14-1:
There are four prescaler settings, specified by bits
CCP1M3:CCP1M0. Whenever the CCP module is
turned off, or the CCP module is not in Capture mode,
the prescaler counter is cleared. This means that any
RESET will clear the prescaler counter.
CLRF
MOVLW
MOVWF
FIGURE 14-1:
CHANGING BETWEEN
CAPTURE PRESCALERS
CCP1CON, F ; Turn CCP module off
NEW_CAPT_PS ; Load WREG with the
; new prescaler mode
; value and CCP ON
CCP1CON
; Load CCP1CON with
; this value
CAPTURE MODE OPERATION BLOCK DIAGRAM
TMR3H
RC2/CCP1 pin
T3CCP2
Prescaler
÷ 1, 4, 16
RXB0IF or
RXB1IF
CCP1CON<3:0>
TMR3L
Set Flag bit CCP1IF
TMR3
Enable
CCPR1H
and
edge detect
T3CCP2
CCPR1L
TMR1
Enable
TMR1H
TMR1L
TMR3H
TMR3L
CCP1M3:CCP1M0
Q’s
Set Flag bit CCP2IF
T3CCP1
T3CCP2
TMR3
Enable
Prescaler
÷ 1, 4, 16
RC1/CCP2 pin
CCPR2H
CCPR2L
TMR1
Enable
and
edge detect
T3CCP2
T3CCP1
TMR1H
TMR1L
CCP2M3:CCP2M0
Q’s
Note:
I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 143
PIC18C601/801
14.4
14.4.2
Compare Mode
Timer1 and/or Timer3 must be running in Timer mode,
or Synchronized Counter mode, if the CCP module is
using the compare feature. In Asynchronous Counter
mode, the compare operation may not work.
In Compare mode, the 16-bit CCPR1 (CCPR2) register
value is constantly compared against either the TMR1
register pair value, or the TMR3 register pair value.
When a match occurs, the RC2/CCP1 (RC1/CCP2) pin
can have one of the following actions:
•
•
•
•
TIMER1/TIMER3 MODE SELECTION
14.4.3
Driven high
Driven low
Toggle output (high to low or low to high)
Remains unchanged
SOFTWARE INTERRUPT MODE
When Generate Software Interrupt is chosen, the
CCP1 pin is not affected. Only a CCP interrupt is generated (if enabled).
The action on the pin is based on the value of control
bits CCP1M3:CCP1M0 (CCP2M3:CCP2M0). At the
same time, interrupt flag bit CCP1IF (CCP2IF) is set.
14.4.4
14.4.1
The special event trigger output of CCP1 resets the
TMR1 register pair. This allows the CCPR1 register to
effectively be a 16-bit programmable period register for
Timer1.
In this mode, an internal hardware trigger is generated,
which may be used to initiate an action.
CCP PIN CONFIGURATION
The user must configure the CCPx pin as an output by
clearing the appropriate TRISC bit.
Note:
Clearing the CCP1CON register will force
the RC2/CCP1 compare output latch to the
default low level. This is not the data latch.
The special trigger output of CCPx resets either the
TMR1, or TMR3 register pair. Additionally, the CCP2
Special Event Trigger will start an A/D conversion, if the
A/D module is enabled.
Note:
FIGURE 14-2:
SPECIAL EVENT TRIGGER
The special event trigger from the CCP2
module will not set the Timer1 or Timer3
interrupt flag bits.
COMPARE MODE OPERATION BLOCK DIAGRAM
Special Event Trigger will:
Reset Timer1 or Timer3 (but not set Timer1 or Timer3 Interrupt Flag bit)
Set bit GO/DONE, which starts an A/D conversion (CCP2 only)
Special Event Trigger
Set Flag bit CCP1IF
CCPR1H CCPR1L
Q
RC2/CCP1
pin
TRISC<2>
Output Enable
S
R
Output
Logic
Comparator
Match
CCP1M3:CCP1M0
Mode Select
0
T3CCP2
TMR1H
1
TMR1L
TMR3H
TMR3L
Special Event Trigger
Set Flag bit CCP2IF
Q
RC1/CCP2
pin
TRISC<1>
Output Enable
Note:
S
R
Output
Logic
T3CCP1
T3CCP2
Match
0
1
Comparator
CCPR2H CCPR2L
CCP2M3:CCP2M0
Mode Select
I/O pins have diode protection to VDD and VSS.
DS39541A-page 144
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 14-3:
REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, TIMER1 AND TIMER3
Value on
POR,
BOR
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
INTCON
GIE/
GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x 0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000 -000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000 -000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000 -000 0000
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
TMR1L
Holding register for the Least Significant Byte of the 16-bit TMR1 Register
xxxx xxxx uuuu uuuu
TMR1H
Holding register for the Most Significant Byte of the 16-bit TMR1 Register
xxxx xxxx uuuu uuuu
T1CON
RD16
—
T1CKPS1 T1CKPS0 T1OSCEN
CCPR1L
Capture/Compare/PWM Register1 (LSB)
CCPR1H
Capture/Compare/PWM Register1 (MSB)
CCP1CON
—
—
DC1B1
DC1B0
CCPR2L
Capture/Compare/PWM Register2 (LSB)
CCPR2H
Capture/Compare/PWM Register2 (MSB)
T1SYNC TMR1CS TMR1ON 0-00 0000 u-uu uuuu
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
CCP1M3
CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
CCP2CON
—
—
DC2B1
DC2B0
CCP2M3
CCP2M2 CCP2M1 CCP2M0 --00 0000 --00 0000
PIR2
—
—
—
—
BCLIF
LVDIF
TMR3IF
CCP2IF
---- 0000 ---- 0000
PIE2
—
—
—
—
BCLIE
LVDIE
TMR3IE
CCP2IE
---- 0000 ---- 0000
IPR2
—
—
—
—
BCLIP
LVDIP
TMR3IP
CCP2IP
---- 0000 ---- 0000
TMR3L
Holding register for the Least Significant Byte of the 16-bit TMR3 register
xxxx xxxx uuuu uuuu
TMR3H
Holding register for the Most Significant Byte of the 16-bit TMR3 register
xxxx xxxx uuuu uuuu
T3CON
Legend:
RD16
T3CCP2 T3CKPS1 T3CKPS0
T3CCP1
T3SYNC TMR3CS TMR3ON 0000 0000 uuuu uuuu
x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by Capture and Timer1.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 145
PIC18C601/801
14.5
14.5.1
PWM Mode
In Pulse Width Modulation (PWM) mode, the CCP1 pin
produces up to a 10-bit resolution PWM output. Since
the CCP1 pin is multiplexed with the PORTC data latch,
the TRISC<2> bit must be cleared to make the CCP1
pin an output.
Note:
Clearing the CCP1CON register will force
the CCP1 PWM output latch to the default
low level. This is not the PORTC I/O data
latch.
Figure 14-3 shows a simplified block diagram of the
CCP module in PWM mode.
For a step-by-step procedure on how to setup the CCP
module for PWM operation, see Section 14.5.3.
FIGURE 14-3:
SIMPLIFIED PWM BLOCK
DIAGRAM
Duty Cycle Registers
PWM PERIOD
The PWM period is specified by writing to the PR2
register. The PWM period can be calculated by the
formula:
PWM period =
[(PR2) + 1] • 4 • TOSC •
(TMR2 prescale value)
where PWM frequency is defined as 1 / [PWM period].
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
• TMR2 is cleared
• The CCP1 pin is set (exception: if PWM duty
cycle = 0%, the CCP1 pin will not be set)
• The PWM duty cycle is latched from CCPR1L into
CCPR1H
Note:
CCP1CON<5:4>
The Timer2 postscaler (see Section 12.1)
is not used in the determination of the
PWM frequency. The postscaler could be
used to have a servo update rate at a different frequency than the PWM output.
CCPR1L (Master)
14.5.2
CCPR1H (Slave)
R
Comparator
Q
RC2/CCP1
(Note 1)
TMR2
S
The PWM duty cycle is specified by writing to the
CCPR1L register and to the CCP1CON<5:4> bits. Up
to 10-bit resolution is available. The CCPR1L contains
the eight MSbs and the CCP1CON<5:4> contains the
two LSbs. This 10-bit value is represented by
CCPR1L:CCP1CON<5:4>. The following equation is
used to calculate the PWM duty cycle in time:
PWM duty cycle =
TRISC<2>
Comparator
Clear Timer,
CCP1 pin and
latch D.C.
PR2
Note 1: 8-bit timer is concatenated with 2-bit internal Q clock, or
2 bits of the prescaler, to create 10-bit time-base.
A PWM output (Figure 14-4) has a time-base (period)
and a time that the output stays high (duty cycle). The
frequency of the PWM is the inverse of the period
(1/period).
FIGURE 14-4:
PWM OUTPUT
Period
PWM DUTY CYCLE
(CCPR1L:CCP1CON<5:4>) •
TOSC • (TMR2 prescale value)
CCPR1L and CCP1CON<5:4> can be written to at any
time, but the duty cycle value is not latched into
CCPR1H until after a match between PR2 and TMR2
occurs (i.e., the period is complete). In PWM mode,
CCPR1H is a read-only register.
The CCPR1H register and a 2-bit internal latch are
used to double buffer the PWM duty cycle. This double
buffering is essential for glitchless PWM operation.
When the CCPR1H and 2-bit latch match TMR2, concatenated with an internal 2-bit Q clock or 2 bits of the
TMR2 prescaler, the CCP1 pin is cleared.
The maximum PWM resolution (bits) for a given PWM
frequency is given by the equation:
F OSC
log  ---------------
 F PWM
PWM Resolution (max) = -----------------------------bits
log ( 2 )
Duty Cycle
TMR2 = PR2
TMR2 = Duty Cycle
Note:
TMR2 = PR2
DS39541A-page 146
Advance Information
If the PWM duty cycle value is longer than
the PWM period, the CCP1 pin will not be
cleared.
 2001 Microchip Technology Inc.
PIC18C601/801
14.5.3
SETUP FOR PWM OPERATION
3.
The following steps should be taken when configuring
the CCP module for PWM operation:
4.
1.
5.
2.
Set the PWM period by writing to the PR2
register.
Set the PWM duty cycle by writing to the
CCPR1L register and CCP1CON<5:4> bits.
TABLE 14-4:
Make the CCP1 pin an output by clearing the
TRISC<2> bit.
Set the TMR2 prescale value and enable Timer2
by writing to T2CON.
Configure the CCP1 module for PWM operation.
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 25 MHz
PWM Frequency
1.53 kHz
6.10 kHz
24.41 kHz
97.66kHz
16
4
1
1
1
1
0FFh
FFh
FFh
3Fh
1Fh
17h
10
10
10
8
7
6.6
Timer Prescaler (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
TABLE 14-5:
195.31 kHz 260.42 kHz
REGISTERS ASSOCIATED WITH PWM AND TIMER2
Value on
POR,
BOR
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
INTCON
GIE/
GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x 0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000 -000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000 -000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000 -000 0000
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
TMR2
Timer2 Module’s Register
0000 0000 0000 0000
Timer2 Module’s Period Register
1111 1111 1111 1111
PR2
T2CON
—
CCPR1L
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
Capture/Compare/PWM Register1 (LSB)
xxxx xxxx uuuu uuuu
CCPR1H Capture/Compare/PWM Register1 (MSB)
CCP1CON
CCPR2L
—
—
DC1B1
DC1B0
xxxx xxxx uuuu uuuu
CCP1M3
CCP1M2 CCP1M1
CCP1M0
--00 0000 --00 0000
Capture/Compare/PWM Register2 (LSB)
xxxx xxxx uuuu uuuu
CCPR2H Capture/Compare/PWM Register2 (MSB)
xxxx xxxx uuuu uuuu
CCP2CON
—
—
DC2B1
DC2B0
CCP2M3
CCP2M0
--00 0000 --00 0000
PIR2
—
—
—
—
BCLIF
LVDIF
TMR3IF
CCP2IF
---- 0000 ---- 0000
PIE2
—
—
—
—
BCLIE
LVDIE
TMR3IE
CCP2IE
---- 0000 ---- 0000
IPR2
—
—
—
—
BCLIP
LVDIP
TMR3IP
CCP2IP
---- 0000 ---- 0000
Legend:
CCP2M2 CCP2M1
x = unknown, u = unchanged, — = unimplemented, read as '0'. Shaded cells are not used by PWM and Timer2.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 147
PIC18C601/801
NOTES:
DS39541A-page 148
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
15.0
MASTER SYNCHRONOUS
SERIAL PORT (MSSP)
MODULE
15.1
Master SSP (MSSP) Module
Overview
The Master Synchronous Serial Port (MSSP) module is
a serial interface useful for communicating with other
peripheral or microcontroller devices. These peripheral
devices may be Serial EEPROMs, shift registers, display drivers, A/D converters, etc. The MSSP module
can operate in one of two modes:
• Serial Peripheral InterfaceTM (SPI)
• Inter-Integrated CircuitTM (I2C)
- Full Master mode
- Slave mode (with general address call)
The I2C interface supports the following modes in
hardware:
• Master mode
• Multi-Master mode
• Slave mode
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 149
PIC18C601/801
15.2
Control Registers
The MSSP module has three associated registers.
These include a status register and two control registers.
REGISTER 15-1:
Register 15-1 shows the MSSP Status Register
(SSPSTAT), Register 15-2 shows the MSSP Control
Register 1 (SSPCON1), and Register 15-3 shows the
MSSP Control Register 2 (SSPCON2).
SSPSTAT REGISTER
R/W-0
R/W-0
R-0
R-0
R-0
R-0
R-0
R-0
SMP
CKE
D/A
P
S
R/W
UA
BF
bit 7
bit 0
bit 7
SMP: Sample bit
SPI Master mode:
1 = Input data sampled at end of data output time
0 = Input data sampled at middle of data output time
SPI Slave mode:
SMP must be cleared when SPI is used in Slave mode
In I2 C Master or Slave mode:
1= Slew rate control disabled for standard speed mode (100 kHz and 1 MHz)
0= Slew rate control enabled for high speed mode (400 kHz)
bit 6
CKE: SPI Clock Edge Select
CKP = 0:
1 = Data transmitted on rising edge of SCK
0 = Data transmitted on falling edge of SCK
CKP = 1:
1 = Data transmitted on falling edge of SCK
0 = Data transmitted on rising edge of SCK
bit 5
D/A: Data/Address bit (I2C mode only)
1 = Indicates that the last byte received or transmitted was data
0 = Indicates that the last byte received or transmitted was address
bit 4
P: STOP bit
(I2C mode only. This bit is cleared when the MSSP module is disabled, SSPEN is cleared.)
1 = Indicates that a STOP bit has been detected last (this bit is ’0’ on RESET)
0 = STOP bit was not detected last
bit 3
S: START bit
(I2C mode only. This bit is cleared when the MSSP module is disabled, SSPEN is cleared.)
1 = Indicates that a START bit has been detected last (this bit is ’0’ on RESET)
0 = START bit was not detected last
bit 2
R/W: Read/Write bit Information (I2C mode only)
This bit holds the R/W bit information following the last address match. This bit is only valid from
the address match to the next START bit, STOP bit, or not ACK bit.
In I2 C Slave mode:
1 = Read
0 = Write
In I2 C Master mode:
1 = Transmit is in progress
0 = Transmit is not in progress.
OR-ing this bit with SEN, RSEN, PEN, RCEN, or ACKEN will indicate if the MSSP is in IDLE mode.
bit 1
UA: Update Address (10-bit I2C mode only)
1 = Indicates that the user needs to update the address in the SSPADD register
0 = Address does not need to be updated
bit 0
BF: Buffer Full Status bit
Receive (SPI and I2 C modes):
1 = Receive complete, SSPBUF is full
0 = Receive not complete, SSPBUF is empty
Transmit (I2 C mode only):
1 = Data transmit in progress (does not include the ACK and STOP bits), SSPBUF is full
0 = Data transmit complete (does not include the ACK and STOP bits), SSPBUF is empty
Legend:
DS39541A-page 150
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 15-2:
SSPCON1 REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
bit 7
bit 0
bit 7
WCOL: Write Collision Detect bit
Master mode:
1 = A write to the SSPBUF register was attempted while the I2C conditions were not valid for a
transmission to be started
0 = No collision
Slave mode:
1 = The SSPBUF register is written while it is still transmitting the previous word (must be cleared in
software)
0 = No collision
bit 6
SSPOV: Receive Overflow Indicator bit
In SPI mode:
1 = A new byte is received while the SSPBUF register is still holding the previous data. In case of
overflow, the data in SSPSR is lost. Overflow can only occur in Slave mode. In Slave mode, the
user must read the SSPBUF, even if only transmitting data, to avoid setting overflow. In Master
mode, the overflow bit is not set since each new reception (and transmission) is initiated by writing
to the SSPBUF register. (Must be cleared in software.)
0 = No overflow
In I2 C mode:
1 = A byte is received while the SSPBUF register is still holding the previous byte. SSPOV is a
"don’t care" in Transmit mode. (Must be cleared in software.)
0 = No overflow
bit 5
SSPEN: Synchronous Serial Port Enable bit
In both modes, when enabled, these pins must be properly configured as input or output.
In SPI mode:
1 = Enables serial port and configures SCK, SDO, SDI, and SS as the source of the serial port pins
0 = Disables serial port and configures these pins as I/O port pins
In I2 C mode:
1 = Enables the serial port and configures the SDA and SCL pins as the source of the serial port pins
0 = Disables serial port and configures these pins as I/O port pins
bit 4
CKP: Clock Polarity Select bit
In SPI mode:
1 = Idle state for clock is a high level
0 = Idle state for clock is a low level
In I2 C Slave mode:
SCK release control
1 = Enable clock
0 = Holds clock low (clock stretch). (Used to ensure data setup time.)
In I2 C Master mode:
Unused in this mode
bit 3 - 0
SSPM3:SSPM0: Synchronous Serial Port Mode Select bits
0000 = SPI Master mode, clock = FOSC/4
0001 = SPI Master mode, clock = FOSC/16
0010 = SPI Master mode, clock = FOSC/64
0011 = SPI Master mode, clock = TMR2 output/2
0100 = SPI Slave mode, clock = SCK pin. SS pin control enabled.
0101 = SPI Slave mode, clock = SCK pin. SS pin control disabled. SS can be used as I/O pin.
0110 = I2C Slave mode, 7-bit address
0111 = I2C Slave mode, 10-bit address
1000 = I2C Master mode, clock = FOSC / (4 * (SSPADD+1) )
1001 = Reserved
1010 = Reserved
1011 = I2C firmware controlled Master mode (Slave idle)
1100 = Reserved
1101 = Reserved
1110 = I2C Slave mode, 7-bit address with START and STOP bit interrupts enabled
1111 = I2C Slave mode, 10-bit address with START and STOP bit interrupts enabled
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 151
PIC18C601/801
REGISTER 15-3:
SSPCON2 REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
bit 7
bit 0
bit 7
GCEN: General Call Enable bit (In I2C Slave mode only)
1 = Enable interrupt when a general call address (0000h) is received in the SSPSR
0 = General call address disabled
bit 6
ACKSTAT: Acknowledge Status bit (In I2C Master mode only)
In Master Transmit mode:
1 = Acknowledge was not received from slave
0 = Acknowledge was received from slave
bit 5
ACKDT: Acknowledge Data bit (In I2C Master mode only)
In Master Receive mode:
Value transmitted when the user initiates an Acknowledge sequence at the end of a receive
1 = Not Acknowledge
0 = Acknowledge
bit 4
ACKEN: Acknowledge Sequence Enable bit (In I2C Master mode only)
In Master Receive mode:
1 = Initiate Acknowledge sequence on SDA and SCL pins, and transmit ACKDT data bit.
Automatically cleared by hardware.
0 = Acknowledge sequence idle
bit 3
RCEN: Receive Enable bit (In I2C Master mode only)
1 = Enables Receive mode for I2C
0 = Receive idle
bit 2
PEN: STOP Condition Enable bit (In I2C Master mode only)
SCK release control
1 = Initiate STOP condition on SDA and SCL pins. Automatically cleared by hardware.
0 = STOP condition idle
bit 1
RSEN: Repeated START Condition Enabled bit (In I2C Master mode only)
1 = Initiate Repeated START condition on SDA and SCL pins. Automatically cleared
by hardware.
0 = Repeated START condition idle
bit 0
SEN: START Condition Enabled bit (In I2C Master mode only)
1 = Initiate START condition on SDA and SCL pins. Automatically cleared by hardware.
0 = START condition idle
Note:
For bits ACKEN, RCEN, PEN, RSEN, SEN: If the I2C module is not in the IDLE
mode, this bit may not be set (no spooling) and the SSPBUF may not be written (or
writes to the SSPBUF are disabled).
Legend:
DS39541A-page 152
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
15.3
FIGURE 15-1:
SPI Mode
The SPI mode allows 8 bits of data to be synchronously
transmitted and received, simultaneously. All four
modes of SPI are supported. To accomplish communication, typically three pins are used:
MSSP BLOCK DIAGRAM
(SPI MODE)
Internal
Data Bus
Read
• Serial Data Out (SDO) - RC5/SDO
• Serial Data In (SDI) - RC4/SDI/SDA
• Serial Clock (SCK) - RC3/SCK/SCL/LVOIN
Write
SSPBUF reg
Additionally, a fourth pin may be used when in any
Slave mode of operation:
SSPSR reg
• Slave Select (SS) - RA5/SS/AN4
SDI
15.3.1
SDO
OPERATION
When initializing the SPI, several options need to be
specified. This is done by programming the appropriate
control bits SSPCON1<5:0> and SSPSTAT<7:6>.
These control bits allow the following to be specified:
•
•
•
•
Master mode (SCK is the clock output)
Slave mode (SCK is the clock input)
Clock polarity (Idle state of SCK)
Data input sample phase (middle or end of data
output time)
• Clock edge (output data on rising/falling edge of
SCK)
• Clock rate (Master mode only)
• Slave Select mode (Slave mode only)
SS Control
Enable
SS
Edge
Select
2
Clock Select
SSPM3:SSPM0
SMP:CKE 4
TMR2 Output
2
2
Edge
Select
Prescaler TOSC
4, 16, 64
(
SCK
Figure 15-1 shows the block diagram of the MSSP
module, when in SPI mode.
)
Data to TX/RX in SSPSR
TRIS bit
Note:
 2001 Microchip Technology Inc.
Shift
Clock
bit0
I/O pins have diode protection to VDD and VSS.
Advance Information
DS39541A-page 153
PIC18C601/801
The MSSP consists of a transmit/receive shift register
(SSPSR) and a buffer register (SSPBUF). The SSPSR
shifts the data in and out of the device, MSb first. The
SSPBUF holds the data that was written to the SSPSR,
until the received data is ready. Once the 8 bits of data
have been received, that byte is moved to the SSPBUF
register. Then the buffer full detect bit, BF (SSPSTAT
register), and the interrupt flag bit, SSPIF (PIR registers), are set. This double buffering of the received data
(SSPBUF) allows the next byte to start reception before
reading the data that was just received. Any write to the
SSPBUF register during transmission/reception of data
will be ignored, and the write collision detect bit, WCOL
(SSPCON1 register), will be set. User software must
clear the WCOL bit so that it can be determined if the
following write(s) to the SSPBUF register completed
successfully.
When the application software is expecting to receive
valid data, the SSPBUF should be read before the next
byte of data to transfer is written to the SSPBUF. The
buffer full (BF) bit (SSPSTAT register) indicates when
SSPBUF has been loaded with the received data
(transmission is complete). When the SSPBUF is read,
the BF bit is cleared. This data may be irrelevant if the
SPI is only a transmitter. Generally, the MSSP interrupt
is used to determine when the transmission/reception
has completed. The SSPBUF must be read and/or
written. If the interrupt method is not going to be used,
then software polling can be done to ensure that a write
collision does not occur. Example 15-1 shows the
loading of the SSPBUF (SSPSR) for data transmission.
EXAMPLE 15-1:
The SSPSR is not directly readable or writable, and
can only be accessed by addressing the SSPBUF register. Additionally, the MSSP status register (SSPSTAT
register) indicates the various status conditions.
15.3.2
ENABLING SPI I/O
To enable the serial port, SSP enable bit, SSPEN
(SSPCON1 register), must be set. To reset or reconfigure SPI mode, clear the SSPEN bit, re-initialize the
SSPCON registers, and then set the SSPEN bit. This
configures the SDI, SDO, SCK, and SS pins as serial
port pins. For the pins to behave as the serial port function, corresponding pins must have their data direction
bits (in the TRIS register) appropriately programmed.
That is:
• SDI is automatically controlled by the SPI module
• SDO must have TRISC<5> bit cleared
• SCK (Master mode) must have TRISC<3> bit
cleared
• SCK (Slave mode) must have TRISC<3> bit set
• RA5 must be configured as digital I/O using
ADCON1 register
• SS must have TRISA<5> bit set
Any serial port function that is not desired may be
overridden by programming the corresponding data
direction (TRIS) register to the opposite value.
LOADING THE SSPBUF (SSPSR) REGISTER
LOOP BTFSS SSPSTAT, BF
BRA LOOP
MOVF SSPBUF, W
;Has data been received (transmit complete)?
;No
;WREG reg = contents of SSPBUF
MOVWF RXDATA
;Save in user RAM, if data is meaningful
MOVF TXDATA, W
MOVWF SSPBUF
;W reg = contents of TXDATA
;New data to xmit
DS39541A-page 154
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
15.3.3
MASTER MODE
The clock polarity is selected by appropriately programming the CKP bit (SSPCON1 register). This, then,
would give waveforms for SPI communication as
shown in Figure 15-2, Figure 15-4, and Figure 15-5,
where the MSb is transmitted first. In Master mode, the
SPI clock rate (bit rate) is user programmable to be one
of the following:
The master can initiate the data transfer at any time
because it controls the SCK. The master determines
when the slave is to broadcast data by the software
protocol.
In Master mode, the data is transmitted/received as
soon as the SSPBUF register is written to. If the SPI is
only going to receive, the SDO output could be disabled (programmed as an input). The SSPSR register
will continue to shift in the signal present on the SDI pin
at the programmed clock rate. As each byte is
received, it will be loaded into the SSPBUF register as
a normal received byte (interrupts and status bits
appropriately set). This could be useful in receiver
applications as a “line activity monitor” mode.
FIGURE 15-2:
•
•
•
•
FOSC/4 (or TCY)
FOSC/16 (or 4 • TCY)
FOSC/64 (or 16 • TCY)
Timer2 output/2
This allows a maximum data rate (at 25 MHz) of 6.25
Mbps.
Figure 15-2 shows the waveforms for Master mode.
When the CKE bit is set, the SDO data is valid before
there is a clock edge on SCK. The change of the input
sample is shown based on the state of the SMP bit. The
time when the SSPBUF is loaded with the received
data is shown.
SPI MODE WAVEFORM (MASTER MODE)
Write to
SSPBUF
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
4 Clock
Modes
SCK
(CKP = 0
CKE = 1)
SCK
(CKP = 1
CKE = 1)
SDO
(CKE = 0)
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
SDO
(CKE = 1)
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
SDI
(SMP = 0)
bit0
bit7
Input
Sample
(SMP = 0)
SDI
(SMP = 1)
bit0
bit7
Input
Sample
(SMP = 1)
SSPIF
Next Q4 Cycle
after Q2↓
SSPSR to
SSPBUF
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 155
PIC18C601/801
15.3.4
SLAVE MODE
In Slave mode, the data is transmitted and received as
the external clock pulses appear on SCK. When the
last bit is latched, the SSPIF interrupt flag bit is set.
While in Slave mode, the external clock is supplied by
the external clock source on the SCK pin. This external
clock must meet the minimum high and low times, as
specified in the electrical specifications.
the SDO pin is no longer driven, even if in the middle of a transmitted byte, and becomes a floating
output. External pull-up/pull-down resistors may be
desirable, depending on the application.
Note 1: When the SPI is in Slave mode with SS
pin control enabled, (SSPCON<3:0> =
0100), the SPI module will reset if the SS
pin is set to VDD.
2: If the SPI is used in Slave mode with CKE
set, then the SS pin control must be
enabled.
While in SLEEP mode, the slave can transmit/receive
data. When a byte is received, the device will wake-up
from SLEEP.
15.3.5
When the SPI module resets, the bit counter is forced
to 0. This can be done by either forcing the SS pin to a
high level, or clearing the SSPEN bit.
SLAVE SELECT
SYNCHRONIZATION
The SS pin allows a Synchronous Slave mode. The
SPI must be in Slave mode with SS pin control
enabled (SSPCON1<3:0> = 04h). The pin must not
be driven low for the SS pin to function as an input.
The data latch must be high. When the SS pin is
low, transmission and reception are enabled and
the SDO pin is driven. When the SS pin goes high,
FIGURE 15-3:
To emulate two-wire communication, the SDO pin can
be connected to the SDI pin. When the SPI needs to
operate as a receiver, the SDO pin can be configured
as an input. This disables transmissions from the SDO.
The SDI can always be left as an input (SDI function),
since it cannot create a bus conflict.
SLAVE SYNCHRONIZATION WAVEFORM
SS
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
Write to
SSPBUF
SDO
SDI
(SMP = 0)
bit7
bit6
bit7
bit0
bit0
bit7
bit7
Input
Sample
(SMP = 0)
SSPIF
Next Q4 Cycle
after Q2↓
SSPSR to
SSPBUF
DS39541A-page 156
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 15-4:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0)
SS
Optional
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
Write to
SSPBUF
SDO
bit7
SDI
(SMP = 0)
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit0
bit7
Input
Sample
(SMP = 0)
SSPIF
Next Q4 Cycle
after Q2↓
SSPSR to
SSPBUF
FIGURE 15-5:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1)
SS
Required
SCK
(CKP = 0
CKE = 1)
SCK
(CKP = 1
CKE = 1)
Write to
SSPBUF
SDO
SDI
(SMP = 0)
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit0
bit7
Input
Sample
(SMP = 0)
SSPIF
Next Q4 Cycle
after Q2↓
SSPSR to
SSPBUF
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 157
PIC18C601/801
15.3.6
SLEEP OPERATION
15.3.8
In Master mode, all module clocks are halted, and the
transmission/reception will remain in that state until the
device wakes from SLEEP. After the device returns to
normal mode, the module will continue to transmit/
receive data.
Table 15-1 shows the compatibility between the standard SPI modes and the states of the CKP and CKE
control bits.
TABLE 15-1:
In Slave mode, the SPI transmit/receive shift register
operates asynchronously to the device. This allows the
device to be placed in SLEEP mode, and data to be
shifted into the SPI transmit/receive shift register.
When all eight bits have been received, the MSSP
interrupt flag bit will be set and, if enabled, will wake the
device from SLEEP.
15.3.7
SPI BUS MODES
Control Bits State
Standard SPI Mode
Terminology
CKP
CKE
0, 0
0, 1
1, 0
1, 1
0
0
1
1
1
0
1
0
EFFECTS OF A RESET
There is also a SMP bit that controls when the data will
be sampled.
A RESET disables the MSSP module and terminates
the current transfer.
TABLE 15-2:
BUS MODE COMPATIBILITY
REGISTERS ASSOCIATED WITH SPI OPERATION
Value on
POR,
BOR
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
INTCON
GIE/
GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF TMR1IF -000 0000 -000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE TMR1IE -000 0000 -000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP TMR1IP -000 0000 -000 0000
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
SSPBUF Synchronous Serial Port Receive Buffer/Transmit Register
SSPCON
WCOL
TRISA
—
SSPSTAT
SMP
SSPOV SSPEN
CKP
SSPM3
SSPM2
xxxx xxxx uuuu uuuu
SSPM1
SSPM0 0000 0000 0000 0000
PORTA Data Direction Register
CKE
D/A
0000 000x 0000 000u
P
--11 1111 --11 1111
S
R/W
UA
BF
0000 0000 0000 0000
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'.
Shaded cells are not used by the MSSP in SPI mode.
DS39541A-page 158
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
15.4
MSSP I2 C Operation
The MSSP module in I 2C mode, fully implements all
master and slave functions (including general call support) and provides interrupts on START and STOP bits
in hardware to determine a free bus (Multi-Master
mode). The MSSP module implements the standard
mode specifications, as well as 7-bit and 10-bit
addressing.
Two pins are used for data transfer. These are the RC3/
SCK/SCL pin, which is the clock (SCL), and the RC4/
SDI/SDA pin, which is the data (SDA). The user must
configure these pins as inputs or outputs through the
TRISC<4:3> bits.
The MSSP module functions are enabled by setting
MSSP Enable bit SSPEN (SSPCON1 register).
The MSSP module has these six registers for I2C operation:
•
•
•
•
•
MSSP Control Register1 (SSPCON1)
MSSP Control Register2 (SSPCON2)
MSSP Status Register (SSPSTAT)
Serial Receive/Transmit Buffer (SSPBUF)
MSSP Shift Register (SSPSR) - Not directly
accessible
• MSSP Address Register (SSPADD)
FIGURE 15-6:
MSSP BLOCK DIAGRAM
(I2C MODE)
Internal
Data Bus
Read
15.4.1
SLAVE MODE
In Slave mode, the SCL and SDA pins must be configured as inputs (TRISC<4:3> set). The MSSP module
will override the input state with the output data when
required (slave-transmitter).
When an address is matched, or the data transfer after
an address match is received, the hardware automatically will generate the acknowledge (ACK) pulse and
load the SSPBUF register with the received value currently in the SSPSR register.
If either or both of the following conditions are true, the
MSSP module will not give this ACK pulse:
The buffer full bit BF (SSPCON1 register) was
set before the transfer was received.
The overflow bit SSPOV (SSPCON1 register)
was set before the transfer was received.
b)
SSPSR reg
In this event, the SSPSR register value is not loaded
into the SSPBUF, but bit SSPIF (PIR registers) is set.
The BF bit is cleared by reading the SSPBUF register,
while bit SSPOV is cleared through software.
LSb
MSb
Match Detect
Addr Match
SSPADD reg
START and
STOP bit Detect
Note:
Selection of any I 2C mode with the SSPEN bit set,
forces the SCL and SDA pins to be open drain, provided these pins are programmed to inputs by setting
the appropriate TRISC bits.
SSPBUF reg
Shift
Clock
RC4/
SDI/
SDA
I2C Master mode, clock = OSC/(4*(SSPADD +1))
I 2C Slave mode (7-bit address)
I 2C Slave mode (10-bit address)
I 2C Slave mode (7-bit address), with START and
STOP bit interrupts enabled
• I 2C Slave mode (10-bit address), with START and
STOP bit interrupts enabled
• I 2C firmware controlled master operation, slave is
idle
•
•
•
•
a)
Write
RC3/SCK/SCL
The SSPCON1 register allows control of the I 2C operation. The SSPM3:SSPM0 mode selection bits
(SSPCON1 register) allow one of the following I 2C
modes to be selected:
The SCL clock input must have a minimum high and
low for proper operation. The high and low times of the
I2C specification, as well as the requirement of the
MSSP module, is shown in timing parameter #100 and
parameter #101.
Set, RESET
S, P bits
(SSPSTAT reg)
I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 159
PIC18C601/801
15.4.1.1
Addressing
15.4.1.2
Once the MSSP module has been enabled, it waits for
a START condition to occur. Following the START condition, the eight bits are shifted into the SSPSR register.
All incoming bits are sampled with the rising edge of the
clock (SCL) line. The value of register SSPSR<7:1> is
compared to the value of the SSPADD register. The
address is compared on the falling edge of the eighth
clock (SCL) pulse. If the addresses match, and the BF
and SSPOV bits are clear, the following events occur:
a)
b)
c)
d)
The SSPSR register value is loaded into the
SSPBUF register.
The buffer full bit BF is set.
An ACK pulse is generated.
MSSP interrupt flag bit SSPIF (PIR registers) is
set on the falling edge of the ninth SCL pulse
(interrupt is generated, if enabled).
In 10-bit Address mode, two address bytes need to be
received by the slave. The five Most Significant bits
(MSb) of the first address byte, specify if this is a 10-bit
address. The R/W bit (SSPSTAT register) must specify
a write so the slave device will receive the second
address byte. For a 10-bit address, the first byte would
equal ‘1111 0 A9 A8 0’, where A9 and A8 are the
two MSb’s of the address.
The sequence of events for 10-bit addressing is as follows, with steps 7- 9 for slave-transmitter:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Receive first (high) byte of address (the SSPIF,
BF and UA bits (SSPSTAT register) are set).
Update the SSPADD register with second (low)
byte of address (clears bit UA and releases the
SCL line).
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
Receive second (low) byte of address (bits
SSPIF, BF, and UA are set).
Update the SSPADD register with the first (high)
byte of address. If match releases SCL line, this
will clear bit UA.
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
Receive repeated START condition.
Receive first (high) byte of address (bits SSPIF
and BF are set).
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
DS39541A-page 160
Reception
When the R/W bit of the address byte is clear and an
address match occurs, the R/W bit of the SSPSTAT
register is cleared. The received address is loaded into
the SSPBUF register.
When the address byte overflow condition exists, then
no acknowledge (ACK) pulse is given. An overflow condition is defined as either bit BF (SSPSTAT register) is
set or bit SSPOV (SSPCON1 register) is set.
An MSSP interrupt is generated for each data transfer
byte. Flag bit SSPIF (PIR registers) must be cleared in
software. The SSPSTAT register is used to determine
the status of the byte.
15.4.1.3
Transmission
When the R/W bit of the incoming address byte is set
and an address match occurs, the R/W bit of the
SSPSTAT register is set. The received address is
loaded into the SSPBUF register. The ACK pulse will
be sent on the ninth bit and pin RC3/SCK/SCL is held
low. The transmit data must be loaded into the
SSPBUF register, which also loads the SSPSR register. Then pin RC3/SCK/SCL should be enabled by setting bit CKP (SSPCON1 register). The master must
monitor the SCL pin prior to asserting another clock
pulse. The slave devices may be holding off the master
by stretching the clock. The eight data bits are shifted
out on the falling edge of the SCL input. This ensures
that the SDA signal is valid during the SCL high time
(Figure 15-8).
An MSSP interrupt is generated for each data transfer
byte. The SSPIF bit must be cleared in software and
the SSPSTAT register is used to determine the status
of the byte. The SSPIF bit is set on the falling edge of
the ninth clock pulse.
As a slave-transmitter, the ACK pulse from the masterreceiver is latched on the rising edge of the ninth SCL
input pulse. If the SDA line is high (not ACK), then the
data transfer is complete. When the ACK is latched by
the slave, the slave logic is reset (resets SSPSTAT register) and the slave monitors for another occurrence of
the START bit. If the SDA line was low (ACK), the transmit data must be loaded into the SSPBUF register, which
also loads the SSPSR register. Pin RC3/SCK/SCL
should be enabled by setting bit CKP.
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
I 2C SLAVE MODE WAVEFORMS FOR RECEPTION (7-BIT ADDRESS)
FIGURE 15-7:
Receiving Address R/W = 0
Receiving Data
Receiving Data
Not ACK
ACK
ACK
A7 A6 A5 A4 A3 A2 A1
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
SDA
SCL
1
S
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
SSPIF
P
Bus Master
Terminates
Transfer
BF
Cleared in software
SSPBUF register is read
SSPOV
Bit SSPOV is set because the SSPBUF register is still full.
ACK is not sent.
I 2C SLAVE MODE WAVEFORMS FOR TRANSMISSION (7-BIT ADDRESS)
FIGURE 15-8:
R/W = 0
Receiving Address
A7
SDA
SCL
S
A6
1
2
Data in
Sampled
R/W = 1
A5
A4
A3
A2
A1
3
4
5
6
7
ACK
8
9
Not ACK
Transmitting Data
D7
1
SCL held low
while CPU
responds to SSPIF
D6
D5
D4
D3
D2
D1
D0
2
3
4
5
6
7
8
9
P
SSPIF
BF
Cleared in software
SSPBUF is written in software
From SSP Interrupt
Service Routine
CKP
Set bit after writing to SSPBUF
(the SSPBUF must be written to
before the CKP bit can be set)
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 161
PIC18C601/801
15.4.2
GENERAL CALL ADDRESS
SUPPORT
If the general call address matches, the SSPSR is
transferred to the SSPBUF, the BF bit is set (eighth bit),
and on the falling edge of the ninth bit (ACK bit), the
SSPIF interrupt flag bit is set.
The addressing procedure for the I2C bus is such that
the first byte after the START condition usually determines which device will be the slave addressed by the
master. The exception is the general call address,
which can address all devices. When this address is
used, all devices should, in theory, respond with an
Acknowledge.
When the interrupt is serviced, the source for the interrupt can be checked by reading the contents of the
SSPBUF. The value can be used to determine if the
address was device specific or a general call address.
In 10-bit mode, the SSPADD is required to be updated
for the second half of the address to match, and the UA
bit is set (SSPSTAT register). If the general call address
is sampled when the GCEN bit is set and while the
slave is configured in 10-bit address mode, then the
second half of the address is not necessary. The UA bit
will not be set, and the slave will begin receiving data
after the Acknowledge (Figure 15-9).
The general call address is one of eight addresses
reserved for specific purposes by the I2C protocol. It
consists of all 0’s with R/W = 0.
The general call address is recognized (enabled) when
the General Call Enable (GCEN) bit is set (SSPCON2
register). Following a START bit detect, eight bits are
shifted into the SSPSR and the address is compared
against the SSPADD. It is also compared to the general
call address and fixed in hardware.
FIGURE 15-9:
SLAVE MODE GENERAL CALL ADDRESS SEQUENCE (7 OR 10-BIT ADDRESS)
Address is compared to General Call Address
after ACK, set interrupt
R/W = 0
ACK D7
General Call Address
SDA
Receiving Data
ACK
D6
D5
D4
D3
D2
D1
D0
2
3
4
5
6
7
8
SCL
S
1
2
3
4
5
6
7
8
9
1
9
SSPIF
BF
Cleared in software
SSPBUF is read
SSPOV
’0’
GCEN
’1’
DS39541A-page 162
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
15.4.3
MASTER MODE
Master mode of operation is supported by interrupt
generation on the detection of the START and STOP
conditions. The STOP (P) and START (S) bits are
cleared from a RESET, or when the MSSP module is
disabled. Control of the I 2C bus may be taken when the
P bit is set, or the bus is idle, with both the S and P bits
clear.
1.
2.
Assert a START condition on SDA and SCL.
Assert a Repeated START condition on SDA
and SCL.
Write to the SSPBUF register initiating transmission of data/address.
Generate a STOP condition on SDA and SCL.
Configure the I2C port to receive data.
Generate an Acknowledge condition at the end
of a received byte of data.
3.
4.
5.
6.
In Master mode, the SCL and SDA lines are manipulated by the MSSP hardware.
The following events will cause SSP Interrupt Flag bit,
SSPIF, to be set (SSP Interrupt if enabled):
•
•
•
•
•
The MSSP module, when configured in I2C
Master mode, does not allow queueing of
events. For instance, the user is not
allowed to initiate a START condition and
immediately write the SSPBUF register to
imitate transmission, before the START
condition is complete. In this case, the
SSPBUF will not be written to and the
WCOL bit will be set, indicating that a write
to the SSPBUF did not occur.
Note:
START condition
STOP condition
Data transfer byte transmitted/received
Acknowledge Transmit
Repeated START condition
I2C MASTER MODE SUPPORT
15.4.4
Master mode is enabled by setting and clearing the
appropriate SSPM bits in SSPCON1 and by setting the
SSPEN bit. Once Master mode is enabled, the user
has the following six options:
MSSP BLOCK DIAGRAM (I2C MASTER MODE)
SSPM3:SSPM0
SSPADD<6:0>
Internal
Data Bus
Read
Write
SSPBUF
Baud
Rate
Generator
Shift
Clock
SDA
SDA In
SSPSR
Receive Enable
MSb
START bit, STOP bit,
Acknowledge
Generate
SCL In
Bus Collision
Note:
START bit Detect
STOP bit Detect
Write Collision Detect
Clock Arbitration
State Counter for
End of XMIT/RCV
Clock Cntl
SCL
LSb
Clock arbitrate/WCOL Detect
(hold off clock source)
FIGURE 15-10:
Set/Reset, S, P, WCOL (SSPSTAT)
Set SSPIF, BCLIF
Reset ACKSTAT, PEN (SSPCON2)
I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 163
PIC18C601/801
15.4.4.1
I2C Master Mode Operation
A typical transmit sequence would go as follows:
The master device generates all of the serial clock
pulses and the START and STOP conditions. A transfer is ended with a STOP condition or with a Repeated
START condition. Since the Repeated START condition is also the beginning of the next serial transfer, the
I2C bus will not be released.
a)
In Master Transmitter mode, serial data is output
through SDA, while SCL outputs the serial clock. The
first byte transmitted contains the slave address of the
receiving device (7 bits) and the Read/Write (R/W) bit.
In this case, the R/W bit will be logic ’0’. Serial data is
transmitted eight bits at a time. After each byte is transmitted, an Acknowledge bit is received. START and
STOP conditions are output to indicate the beginning
and the end of a serial transfer.
c)
In Master Receive mode, the first byte transmitted contains the slave address of the transmitting device
(7 bits) and the R/W bit. In this case, the R/W bit will be
logic ’1’. Thus, the first byte transmitted is a 7-bit slave
address followed by a ’1’ to indicate receive bit. Serial
data is received via SDA, while SCL outputs the serial
clock. Serial data is received eight bits at a time. After
each byte is received, an Acknowledge bit is transmitted. START and STOP conditions indicate the beginning and end of transmission.
The baud rate generator used for the SPI mode operation is now used to set the SCL clock frequency for
either 100 kHz, 400 kHz, or 1 MHz I2C operation. The
baud rate generator reload value is contained in the
lower 7 bits of the SSPADD register. The baud rate
generator will automatically begin counting on a write to
the SSPBUF. Once the given operation is complete
(i.e., transmission of the last data bit is followed by
ACK), the internal clock will automatically stop counting
and the SCL pin will remain in its last state.
FIGURE 15-11:
b)
d)
e)
f)
g)
h)
i)
j)
k)
l)
15.4.5
BAUD RATE GENERATOR
In I2C Master mode, the reload value for the BRG is
located in the lower 7 bits of the SSPADD register
(Figure 15-11). When the BRG is loaded with this
value, the BRG counts down to 0 and stops until
another reload has taken place. The BRG count is decremented twice per instruction cycle (TCY) on the Q2
and Q4 clocks. In I2C Master mode, the BRG is
reloaded automatically. If clock arbitration is taking
place, for instance, the BRG will be reloaded when the
SCL pin is sampled high (Figure 15-12).
BAUD RATE GENERATOR BLOCK DIAGRAM
SSPM3:SSPM0
SSPM3:SSPM0
Reload
SCL
Control
CLKOUT
DS39541A-page 164
The user generates a START condition by setting the START enable (SEN) bit (SSPCON2
register).
SSPIF is set. The MSSP module will wait the
required start time before any other operation
takes place.
The user loads the SSPBUF with the address to
transmit.
Address is shifted out the SDA pin until all eight
bits are transmitted.
The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
ACKSTAT bit (SSPCON2 register).
The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the SSPIF
bit.
The user loads the SSPBUF with eight bits of
data.
Data is shifted out the SDA pin until all eight bits
are transmitted.
The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
ACKSTAT bit (SSPCON2 register).
The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the SSPIF
bit.
The user generates a STOP condition by setting
the STOP enable bit PEN (SSPCON2 register).
Interrupt is generated once the STOP condition
is complete.
SSPADD<6:0>
Reload
BRG Down Counter
Advance Information
FOSC/4
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 15-12:
BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
SDA
DX
DX-1
SCL allowed to transition high
SCL de-asserted but slave holds
SCL low (clock arbitration)
SCL
BRG decrements on
Q2 and Q4 cycles
BRG
value
03h
02h
01h
00h (hold off)
03h
02h
SCL is sampled high, reload takes
place and BRG starts its count
BRG
reload
15.4.6
I2C MASTER MODE START
CONDITION TIMING
Note:
To initiate a START condition, the user sets the START
Condition Enable (SEN) bit (SSPCON2 register). If the
SDA and SCL pins are sampled high, the baud rate
generator is re-loaded with the contents of
SSPADD<6:0> and starts its count. If SCL and SDA are
both sampled high when the baud rate generator times
out (TBRG), the SDA pin is driven low. The action of the
SDA being driven low while SCL is high, is the START
condition, and causes the S bit (SSPSTAT register) to
be set. Following this, the baud rate generator is
reloaded with the contents of SSPADD<6:0> and
resumes its count. When the baud rate generator times
out (TBRG), the SEN bit (SSPCON2 register) will be
automatically cleared by hardware, the baud rate generator is suspended leaving the SDA line held low and
the START condition is complete.
FIGURE 15-13:
If at the beginning of the START condition,
the SDA and SCL pins are already sampled low, or if during the START condition
the SCL line is sampled low before the
SDA line is driven low, a bus collision
occurs, the Bus Collision Interrupt Flag
BCLIF is set, the START condition is
aborted, and the I2C module is reset into its
IDLE state.
15.4.6.1
WCOL Status Flag
If the user writes the SSPBUF when a START
sequence is in progress, the WCOL is set and the contents of the buffer are unchanged (the write doesn’t
occur).
Note:
Because queueing of events is not
allowed, writing to the lower 5 bits of
SSPCON2 is disabled until the START
condition is complete.
FIRST START BIT TIMING
Set S bit (SSPSTAT)
Write to SEN bit occurs here
SDA = 1,
SCL = 1
TBRG
At completion of START bit,
Hardware clears SEN bit
and sets SSPIF bit
TBRG
Write to SSPBUF occurs here
1st bit
SDA
2nd bit
TBRG
SCL
TBRG
S
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 165
PIC18C601/801
15.4.7
I2C MASTER MODE REPEATED
START CONDITION TIMING
Immediately following the SSPIF bit getting set, the
user may write the SSPBUF with the 7-bit address in
7-bit mode, or the default first address in 10-bit mode.
After the first eight bits are transmitted and an ACK is
received, the user may then transmit an additional
eight bits of address (10-bit mode) or eight bits of data
(7-bit mode).
A Repeated START condition occurs when the RSEN
bit (SSPCON2 register) is programmed high and the
I2C logic module is in the IDLE state. When the RSEN
bit is set, the SCL pin is asserted low. When the SCL
pin is sampled low, the baud rate generator is loaded
with the contents of SSPADD<5:0> and begins counting. The SDA pin is released (brought high) for one
baud rate generator count (TBRG). When the baud rate
generator times out, if SDA is sampled high, the SCL pin
will be de-asserted (brought high). When SCL is sampled high, the baud rate generator is re-loaded with the
contents of SSPADD<6:0> and begins counting. SDA
and SCL must be sampled high for one TBRG. This
action is then followed by assertion of the SDA pin (SDA
= 0) for one TBRG, while SCL is high. Following this, the
RSEN bit (SSPCON2 register) will be automatically
cleared and the baud rate generator will not be reloaded,
leaving the SDA pin held low. As soon as a START condition is detected on the SDA and SCL pins, the S bit
(SSPSTAT register) will be set. The SSPIF bit will not be
set until the baud rate generator has timed out.
15.4.7.1
WCOL Status Flag
If the user writes the SSPBUF when a Repeated
START sequence is in progress, the WCOL is set and
the contents of the buffer are unchanged (the write
doesn’t occur).
Note:
Because queueing of events is not
allowed, writing of the lower 5 bits of
SSPCON2 is disabled until the Repeated
START condition is complete.
Note 1: If RSEN is programmed while any other
event is in progress, it will not take effect.
2: A bus collision during the Repeated
START condition occurs, if:
• SDA is sampled low when SCL goes
from low to high.
• SCL goes low before SDA is
asserted low. This may indicate that
another master is attempting to
transmit a data "1".
FIGURE 15-14:
REPEATED START CONDITION WAVEFORM
Set S (SSPSTAT<3>)
Write to SSPCON2
occurs here.
SDA = 1,
SCL (no change)
SDA = 1,
SCL = 1
TBRG
TBRG
At completion of START bit,
hardware clear RSEN bit
and set SSPIF
TBRG
1st Bit
SDA
Write to SSPBUF occurs here
Falling edge of ninth clock
End of Xmit
TBRG
SCL
TBRG
Sr = Repeated START
DS39541A-page 166
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
15.4.8
I2C MASTER MODE
TRANSMISSION
15.4.8.2
Transmission of a data byte, a 7-bit address, or the
other half of a 10-bit address, is accomplished by simply writing a value to the SSPBUF register. This action
will set the Buffer Full bit, BF, and allow the baud rate
generator to begin counting and start the next transmission. Each bit of address/data will be shifted out onto
the SDA pin after the falling edge of SCL is asserted
(see data hold time specification parameter 106). SCL
is held low for one baud rate generator rollover count
(TBRG). Data should be valid before SCL is released
high (see data setup time specification parameter 107).
When the SCL pin is released high, it is held that way
for TBRG. The data on the SDA pin must remain stable
for that duration and some hold time after the next falling edge of SCL. After the eighth bit is shifted out (the
falling edge of the eighth clock), the BF bit is cleared
and the master releases SDA, allowing the slave
device being addressed to respond with an ACK bit
during the ninth bit time, if an address match occurs, or
if data was received properly. The status of ACK is written into the ACKDT bit on the falling edge of the ninth
clock. If the master receives an Acknowledge, the
Acknowledge Status bit, ACKSTAT, is cleared; if not,
the bit is set. After the ninth clock, the SSPIF bit is set
and the master clock (baud rate generator) is
suspended until the next data byte is loaded into the
SSPBUF, leaving SCL low and SDA unchanged
(Figure 15-15).
After the write to the SSPBUF, each bit of address will
be shifted out on the falling edge of SCL, until all seven
address bits and the R/W bit, are completed. On the
falling edge of the eighth clock, the master will deassert the SDA pin, allowing the slave to respond with
an Acknowledge. On the falling edge of the ninth clock,
the master will sample the SDA pin to see if the address
was recognized by a slave. The status of the ACK bit is
loaded into the ACKSTAT status bit (SSPCON2
register). Following the falling edge of the ninth clock
transmission of the address, the SSPIF is set, the BF
bit is cleared and the baud rate generator is turned off,
until another write to the SSPBUF takes place, holding
SCL low and allowing SDA to float.
15.4.8.1
BF Status Flag
In Transmit mode, the BF bit (SSPSTAT register) is set
when the CPU writes to SSPBUF, and is cleared when
all eight bits are shifted out.
WCOL Status Flag
If the user writes the SSPBUF when a transmit is
already in progress (i.e., SSPSR is still shifting out a
data byte), the WCOL is set and the contents of the
buffer are unchanged (the write doesn’t occur).
WCOL must be cleared in software.
15.4.8.3
ACKSTAT Status Flag
In Transmit mode, the ACKSTAT bit (SSPCON2
register) is cleared when the slave has sent an
Acknowledge (ACK = 0), and is set when the slave
does not Acknowledge (ACK = 1). A slave sends an
Acknowledge when it has recognized its address
(including a general call), or when the slave has
properly received its data.
15.4.9
I2C MASTER MODE RECEPTION
Master mode reception is enabled by programming the
Receive Enable bit, RCEN (SSPCON2 register).
Note:
The MSSP module must be in an IDLE
state before the RCEN bit is set, or the
RCEN bit will be disregarded.
The baud rate generator begins counting and on each
rollover, the state of the SCL pin changes (high to low/
low to high) and data is shifted into the SSPSR. After
the falling edge of the eighth clock, the RCEN bit is
automatically cleared, the contents of the SSPSR are
loaded into the SSPBUF, the BF bit is set, the SSPIF
flag bit is set and the baud rate generator is suspended
from counting, holding SCL low. The MSSP is now in
IDLE state, awaiting the next command. When the
buffer is read by the CPU, the BF bit is automatically
cleared. The user can then send an Acknowledge bit at
the end of reception, by setting the Acknowledge
Sequence Enable bit ACKEN (SSPCON2 register).
15.4.9.1
BF Status Flag
In receive operation, the BF bit is set when an address
or data byte is loaded into SSPBUF from SSPSR. It is
cleared when the SSPBUF register is read.
15.4.9.2
SSPOV Status Flag
In receive operation, the SSPOV bit is set when eight
bits are received into the SSPSR and the BF bit is
already set from a previous reception.
15.4.9.3
WCOL Status Flag
If the user writes the SSPBUF when a receive is
already in progress (i.e., SSPSR is still shifting in a data
byte), the WCOL bit is set and the contents of the buffer
are unchanged (the write doesn’t occur).
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 167
DS39541A-page 168
Advance Information
R/W
PEN
SEN
BF
SSPIF
SCL
SDA
S
A6
A5
A4
A3
A2
A1
3
4
5
Cleared in software
2
6
7
8
9
D7
1
SCL held low
while CPU
responds to SSPIF
After START condition, SEN cleared by hardware.
SSPBUF written
1
ACK = 0
R/W = 0
SSPBUF written with 7-bit address and R/W
start transmit
A7
Transmit Address to Slave
3
D5
4
D4
5
D3
6
D2
7
D1
8
D0
SSPBUF is written in software
Cleared in software service routine
From SSP interrupt
2
D6
Transmitting Data or Second Half
of 10-bit Address
From Slave, clear ACKSTAT bit SSPCON2<6>
P
Cleared in software
9
ACK
ACKSTAT in
SSPCON2 = 1
FIGURE 15-15:
SEN = 0
Write SSPCON2<0> SEN = 1
START condition begins
PIC18C601/801
I 2C MASTER MODE WAVEFORM (TRANSMISSION, 7 OR 10-BIT ADDRESS)
 2001 Microchip Technology Inc.
 2001 Microchip Technology Inc.
S
Advance Information
ACKEN
SSPOV
BF
SDA = 0, SCL = 1
while CPU
responds to SSPIF
SSPIF
SCL
SDA
1
A7
2
4
5
Cleared in software
3
6
A6 A5 A4 A3 A2
Transmit Address to Slave
7
A1
8
9
R/W = 1
ACK
ACK from Slave
2
3
5
6
7
8
D0
9
ACK
2
3
4
5
6
7
Cleared in software
Set SSPIF interrupt
at end of Acknowledge
sequence
Data shifted in on falling edge of CLK
1
D7 D6 D5 D4 D3 D2 D1
Cleared in
software
Set SSPIF at end
of receive
9
ACK is not sent
ACK
P
Set SSPIF interrupt
at end of Acknowledge sequence
Bus Master
terminates
transfer
Set P bit
(SSPSTAT<4>)
and SSPIF
PEN bit = 1
written here
SSPOV is set because
SSPBUF is still full
8
D0
RCEN cleared
automatically
Set ACKEN, start Acknowledge sequence
SDA = ACKDT = 1
Receiving Data from Slave
RCEN = 1 start
next receive
ACK from Master
SDA = ACKDT = 0
Last bit is shifted into SSPSR and
contents are unloaded into SSPBUF
Cleared in software
Set SSPIF interrupt
at end of receive
4
Cleared in software
1
D7 D6 D5 D4 D3 D2 D1
Receiving Data from Slave
RCEN cleared
automatically
Master configured as a Receiver
by programming SSPCON2<3>, (RCEN = 1)
FIGURE 15-16:
SEN = 0
Write to SSPBUF occurs here
Start XMIT
Write to SSPCON2<0> (SEN = 1)
Begin START condition
Write to SSPCON2<4>
to start Acknowledge sequence
SDA = ACKDT (SSPCON2<5>) = 0
PIC18C601/801
I 2C MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESS)
DS39541A-page 169
PIC18C601/801
15.4.10
ACKNOWLEDGE SEQUENCE
TIMING
15.4.11
A STOP bit is asserted on the SDA pin at the end of a
receive/transmit by setting the Stop Sequence Enable
bit, PEN (SSPCON2 register). At the end of a receive/
transmit, the SCL line is held low after the falling edge
of the ninth clock. When the PEN bit is set, the master
will assert the SDA line low. When the SDA line is sampled low, the baud rate generator is reloaded and
counts down to 0. When the baud rate generator times
out, the SCL pin will be brought high, and one TBRG
(baud rate generator rollover count) later, the SDA pin
will be de-asserted. When the SDA pin is sampled high
while SCL is high, the P bit (SSPSTAT register) is set.
A TBRG later, the PEN bit is cleared and the SSPIF bit
is set (Figure 15-18).
An Acknowledge sequence is enabled by setting the
Acknowledge Sequence enable bit, ACKEN (SSPCON2
register). When this bit is set, the SCL pin is pulled low
and the contents of the Acknowledge Data bit (ACKDT)
is presented on the SDA pin. If the user wishes to generate an Acknowledge, then the ACKDT bit should be
cleared. If not, the user should set the ACKDT bit before
starting an Acknowledge sequence. The baud rate generator then counts for one rollover period (TBRG) and the
SCL pin is de-asserted (pulled high). When the SCL pin
is sampled high (clock arbitration), the baud rate generator counts for TBRG. The SCL pin is then pulled low. Following this, the ACKEN bit is automatically cleared, the
baud rate generator is turned off and the MSSP module
then goes into IDLE mode (Figure 15-17).
15.4.11.1
WCOL Status Flag
If the user writes the SSPBUF when a STOP sequence
is in progress, then the WCOL bit is set and the contents
of the buffer are unchanged (the write doesn’t occur).
15.4.10.1 WCOL Status Flag
If the user writes the SSPBUF when an Acknowledge
sequence is in progress, then WCOL is set and the contents of the buffer are unchanged (the write doesn’t occur).
FIGURE 15-17:
STOP CONDITION TIMING
ACKNOWLEDGE SEQUENCE WAVEFORM
Acknowledge sequence starts here,
Write to SSPCON2
ACKEN = 1, ACKDT = 0
ACKEN automatically cleared
TBRG
TBRG
SDA
ACK
D0
SCL
8
9
SSPIF
Cleared in
software
Set SSPIF at the end
of receive
Cleared in
software
Set SSPIF at the end
of Acknowledge sequence
Note: TBRG = one baud rate generator period.
FIGURE 15-18:
STOP CONDITION RECEIVE OR TRANSMIT MODE
SCL = 1 for TBRG, followed by SDA = 1 for TBRG
after SDA sampled high, P bit (SSPSTAT) is set
Write to SSPCON2
Set PEN
PEN bit (SSPCON2) is cleared by
hardware and the SSPIF bit is set
Falling edge of
9th clock
TBRG
SCL
SDA
ACK
P
TBRG
TBRG
TBRG
SCL brought high after TBRG
SDA asserted low before rising edge of clock
to set up STOP condition
Note:
TBRG = one baud rate generator period.
DS39541A-page 170
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
15.4.12
CLOCK ARBITRATION
15.4.13
Clock arbitration occurs when the master, during any
receive, transmit or Repeated START/STOP condition,
de-asserts the SCL pin (SCL allowed to float high).
When the SCL pin is allowed to float high, the baud rate
generator (BRG) is suspended from counting until the
SCL pin is actually sampled high. When the SCL pin is
sampled high, the baud rate generator is reloaded with
the contents of SSPADD<6:0> and begins counting.
This ensures that the SCL high time will always be at
least one BRG rollover count, in the event that the clock
is held low by an external device (Figure 15-19).
FIGURE 15-19:
SLEEP OPERATION
While in SLEEP mode, the I2C module can receive
addresses or data, and when an address match or
complete byte transfer occurs, wake the processor
from SLEEP (if the MSSP interrupt is enabled).
15.4.14
EFFECT OF A RESET
A RESET disables the MSSP module and terminates
the current transfer.
CLOCK ARBITRATION TIMING IN MASTER TRANSMIT MODE
BRG overflow,
Release SCL,
If SCL = 1, load BRG with
SSPADD<6:0> and start count
to measure high time interval
BRG overflow occurs,
Release SCL, Slave device holds SCL low.
SCL = 1 BRG starts counting
clock high interval.
SCL
SCL line sampled once every machine cycle (TOSC² 4).
Hold off BRG until SCL is sampled high.
SDA
TBRG
 2001 Microchip Technology Inc.
TBRG
Advance Information
TBRG
DS39541A-page 171
PIC18C601/801
15.4.15
MULTI-MASTER MODE
In Multi-Master mode, the interrupt generation on the
detection of the START and STOP conditions allows
the determination of when the bus is free. The STOP
(P) and START (S) bits are cleared from a RESET, or
when the MSSP module is disabled. Control of the I 2C
bus may be taken when the P bit (SSPSTAT register) is
set, or the bus is idle, with both the S and P bits clear.
When the bus is busy, enabling the SSP interrupt will
generate the interrupt when the STOP condition
occurs.
In Multi-Master operation, the SDA line must be monitored for arbitration, to see if the signal level is the
expected output level. This check is performed in hardware, with the result placed in the BCLIF bit.
Arbitration can be lost in the following states:
•
•
•
•
•
Address transfer
Data transfer
A START condition
A Repeated START condition
An Acknowledge condition
15.4.16
If a transmit was in progress when the bus collision
occurred, the transmission is halted, the BF bit is
cleared, the SDA and SCL lines are de-asserted, and
the SSPBUF can be written to. When the user services
the bus collision Interrupt Service Routine, and if the
I2C bus is free, the user can resume communication by
asserting a START condition.
If a START, Repeated START, STOP, or Acknowledge
condition was in progress when the bus collision
occurred, the condition is aborted, the SDA and SCL
lines are de-asserted, and the respective control bits in
the SSPCON2 register are cleared. When the user services the bus collision Interrupt Service Routine, and if
the I2C bus is free, the user can resume communication
by asserting a START condition.
The master will continue to monitor the SDA and SCL
pins. If a STOP condition occurs, the SSPIF bit will be
set.
A write to the SSPBUF will start the transmission of
data at the first data bit, regardless of where the transmitter left off when the bus collision occurred.
MULTI -MASTER
COMMUNICATION, BUS
COLLISION, AND BUS
ARBITRATION
Multi-Master mode support is achieved by bus arbitration. When the master outputs address/data bits onto
the SDA pin, arbitration takes place when the master
outputs a '1' on SDA, by letting SDA float high and
another master asserts a '0'. When the SCL pin floats
high, data should be stable. If the expected data on
FIGURE 15-20:
SDA is a '1' and the data sampled on the SDA pin = '0',
then a bus collision has taken place. The master will set
the Bus Collision Interrupt Flag (BCLIF) and reset the
I2C port to its IDLE state. (Figure 15-20).
In Multi-Master mode, the interrupt generation on the
detection of START and STOP conditions allows the
determination of when the bus is free. Control of the I2C
bus can be taken when the P bit is set in the SSPSTAT
register, or the bus is idle and the S and P bits are
cleared.
BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE
Data changes
while SCL = 0
SDA line pulled low
by another source
SDA released
by Master
Sample SDA. While SCL is high,
data doesn’t match what is driven
by the master.
Bus collision has occurred.
SDA
Set bus collision
interrupt (BCLIF)
SCL
BCLIF
DS39541A-page 172
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
15.4.16.1
Bus Collision During a START
Condition
During a START condition, a bus collision occurs if:
a)
SDA or SCL are sampled low at the beginning of
the START condition (Figure 15-21).
SCL is sampled low before SDA is asserted low
(Figure 15-22).
b)
During a START condition, both the SDA and the SCL
pins are monitored.
If the SDA pin is sampled low during this count, the
BRG is reset and the SDA line is asserted early
(Figure 15-23). If, however, a '1' is sampled on the SDA
pin, the SDA pin is asserted low at the end of the BRG
count. The baud rate generator is then reloaded and
counts down to 0, and during this time, if the SCL pin is
sampled as '0', a bus collision does not occur. At the
end of the BRG count, the SCL pin is asserted low.
Note:
If the SDA pin is already low, or the SCL pin is already
low, then all of the following occur:
• the START condition is aborted;
• the BCLIF flag is set, and
• the MSSP module is reset to its IDLE state
(Figure 15-21).
The START condition begins with the SDA and SCL
pins de-asserted. When the SDA pin is sampled high,
the baud rate generator is loaded from SSPADD<6:0>
and counts down to 0. If the SCL pin is sampled low
while SDA is high, a bus collision occurs, because it is
assumed that another master is attempting to drive a
data '1' during the START condition.
FIGURE 15-21:
The reason that bus collision is not a factor
during a START condition, is that no two
bus masters can assert a START condition
at the exact same time. Therefore, one
master will always assert SDA before the
other. This condition does not cause a bus
collision, because the two masters must be
allowed to arbitrate the first address following the START condition. If the address is
the same, arbitration must be allowed to
continue into the data portion, Repeated
START or STOP conditions.
BUS COLLISION DURING START CONDITION (SDA ONLY)
SDA goes low before the SEN bit is set.
. Set BCLIF,
S bit and SSPIF set because
SDA = 0, SCL = 1.
SDA
SCL
Set SEN, enable START
condition if SDA = 1, SCL=1
SEN cleared automatically because of bus collision.
SSP module reset into IDLE state.
SEN
BCLIF
SDA sampled low before
START condition. Set BCLIF.
S bit and SSPIF set because
SDA = 0, SCL = 1.
SSPIF and BCLIF are
cleared in software.
S
SSPIF
SSPIF and BCLIF are
cleared in software.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 173
PIC18C601/801
FIGURE 15-22:
BUS COLLISION DURING START CONDITION (SCL = 0)
SDA = 0, SCL = 1
TBRG
TBRG
SDA
Set SEN, enable START
sequence if SDA = 1, SCL = 1
SCL
SCL = 0 before SDA = 0,
Bus collision occurs, set BCLIF
SEN
SCL = 0 before BRG time-out,
Bus collision occurs, set BCLIF
BCLIF
Interrupt cleared
in software
S
’0’
’0’
SSPIF
’0’
’0’
FIGURE 15-23:
BRG RESET DUE TO SDA ARBITRATION DURING START CONDITION
SDA = 0, SCL = 1
Set S
Less than TBRG
SDA
SCL
Set SSPIF
TBRG
SDA pulled low by other Master.
Reset BRG and assert SDA.
S
SCL pulled low after BRG
Time-out
SEN
BCLIF
Set SEN, enable START
sequence if SDA = 1, SCL = 1
’0’
S
SSPIF
SDA = 0, SCL = 1
Set SSPIF
DS39541A-page 174
Advance Information
Interrupts cleared
in software
 2001 Microchip Technology Inc.
PIC18C601/801
15.4.16.2
Bus Collision During a Repeated
START Condition
reloaded and begins counting. If SDA goes from high to
low before the BRG times out, no bus collision occurs
because no two masters can assert SDA at exactly the
same time.
During a Repeated START condition, a bus collision
occurs if:
a)
b)
If SCL goes from high to low before the BRG times out
and SDA has not already been asserted, a bus collision
occurs. In this case, another master is attempting to
transmit a data ’1’ during the Repeated START condition (Figure 15-25).
A low level is sampled on SDA when SCL goes
from low level to high level.
SCL goes low before SDA is asserted low,
indicating that another master is attempting to
transmit a data ’1’.
If, at the end of the BRG time-out both SCL and SDA
are still high, the SDA pin is driven low and the BRG is
reloaded and begins counting. At the end of the count,
regardless of the status of the SCL pin, the SCL pin is
driven low and the Repeated START condition is
complete.
When the user de-asserts SDA and the pin is allowed
to float high, the BRG is loaded with SSPADD<6:0>
and counts down to 0. The SCL pin is then de-asserted
and when sampled high, the SDA pin is sampled.
If SDA is low, a bus collision has occurred (i.e., another
master is attempting to transmit a data ’0’, see
Figure 15-24). If SDA is sampled high, the BRG is
FIGURE 15-24:
BUS COLLISION DURING A REPEATED START CONDITION (CASE 1)
SDA
SCL
Sample SDA when SCL goes high.
If SDA = 0, set BCLIF and release SDA and SCL.
RSEN
BCLIF
Cleared in software
'0'
S
'0'
SSPIF
FIGURE 15-25:
BUS COLLISION DURING REPEATED START CONDITION (CASE 2)
TBRG
TBRG
SDA
SCL
BCLIF
SCL goes low before SDA.
Set BCLIF, release SDA and SCL.
Interrupt cleared
in software
RSEN
’0’
S
SSPIF
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 175
PIC18C601/801
15.4.16.3
Bus Collision During a STOP
Condition
The STOP condition begins with SDA asserted low.
When SDA is sampled low, the SCL pin is allowed to
float. When the pin is sampled high (clock arbitration),
the baud rate generator is loaded with SSPADD<6:0>
and counts down to 0. After the BRG times out, SDA is
sampled. If SDA is sampled low, a bus collision has
occurred. This is due to another master attempting to
drive a data ’0’ (Figure 15-26). If the SCL pin is sampled
low before SDA is allowed to float high, a bus collision
occurs. This is another case of another master attempting to drive a data ’0’ (Figure 15-27).
Bus collision occurs during a STOP condition if:
a)
b)
After the SDA pin has been de-asserted and
allowed to float high, SDA is sampled low after
the BRG has timed out.
After the SCL pin is de-asserted, SCL is sampled low before SDA goes high.
FIGURE 15-26:
BUS COLLISION DURING A STOP CONDITION (CASE 1)
TBRG
TBRG
SDA sampled
low after TBRG,
set BCLIF
TBRG
SDA
SDA asserted low
SCL
PEN
BCLIF
P
’0’
SSPIF
’0’
FIGURE 15-27:
BUS COLLISION DURING A STOP CONDITION (CASE 2)
TBRG
TBRG
TBRG
SDA
Assert SDA
SCL
SCL goes low before SDA goes high,
set BCLIF
PEN
BCLIF
P
’0’
SSPIF
’0’
DS39541A-page 176
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
16.0
ADDRESSABLE UNIVERSAL
SYNCHRONOUS
ASYNCHRONOUS RECEIVER
TRANSMITTER (USART)
The USART can be configured in the following modes:
• Asynchronous (full duplex)
• Synchronous - Master (half duplex)
• Synchronous - Slave (half duplex)
The SPEN (RCSTA register) and the TRISC<7> bits
have to be set, and the TRISC<6> bit must be
cleared, in order to configure pins RC6/TX/CK and
RC7/RX/DT as the Universal Synchronous Asynchronous Receiver Transmitter.
The Universal Synchronous Asynchronous Receiver
Transmitter (USART) module is one of the two serial
I/O modules. (USART is also known as a Serial Communications Interface or SCI.) The USART can be configured as a full duplex asynchronous system that can
communicate with peripheral devices, such as CRT terminals and personal computers, or it can be configured
as a half duplex synchronous system that can communicate with peripheral devices, such as A/D or D/A integrated circuits, serial EEPROMs, etc.
REGISTER 16-1:
Register 16-1 shows the Transmit Status and Control
Register (TXSTA) and Register 16-2 shows the
Receive Status and Control Register (RCSTA).
TXSTA REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
U-0
R/W-0
R-1
R/W-0
CSRC
TX9
TXEN
SYNC
—
BRGH
TRMT
TX9D
bit 7
bit 0
bit 7
CSRC: Clock Source Select bit
Asynchronous mode:
Don’t care
Synchronous mode:
1 = Master mode (Clock generated internally from BRG)
0 = Slave mode (Clock from external source)
bit 6
TX9: 9-bit Transmit Enable bit
1 = Selects 9-bit transmission
0 = Selects 8-bit transmission
bit 5
TXEN: Transmit Enable bit
1 = Transmit enabled
0 = Transmit disabled
SREN/CREN overrides TXEN in SYNC mode.
bit 4
SYNC: USART Mode Select bit
1 = Synchronous mode
0 = Asynchronous mode
bit 3
Unimplemented: Read as '0'
bit 2
BRGH: High Baud Rate Select bit
Asynchronous mode:
1 = High speed
0 = Low speed
Synchronous mode:
Unused in this mode
bit 1
TRMT: Transmit Shift Register Status bit
1 = TSR empty
0 = TSR full
bit 0
TX9D: 9th bit of Transmit Data. Can be Address/Data bit or a parity bit.
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 177
PIC18C601/801
REGISTER 16-2:
RCSTA REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R-0
R-0
R-x
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
bit 7
bit 0
bit 7
SPEN: Serial Port Enable bit
1 = Serial port enabled (Configures RX/DT and TX/CK pins as serial port pins)
0 = Serial port disabled
bit 6
RX9: 9-bit Receive Enable bit
1 = Selects 9-bit reception
0 = Selects 8-bit reception
bit 5
SREN: Single Receive Enable bit
Asynchronous mode:
Don’t care
Synchronous mode - Master:
1 = Enables single receive
0 = Disables single receive
This bit is cleared after reception is complete.
Synchronous mode - Slave:
Unused in this mode
bit 4
CREN: Continuous Receive Enable bit
Asynchronous mode:
1 = Enables continuous receive
0 = Disables continuous receive
Synchronous mode:
1 = Enables continuous receive until enable bit CREN is cleared (CREN overrides SREN)
0 = Disables continuous receive
bit 3
ADDEN: Address Detect Enable bit
Asynchronous mode 9-bit (RX9 = 1):
1 = Enables address detection, enable interrupt and load of the receive buffer when RSR<8>
is set
0 = Disables address detection, all bytes are received, and ninth bit can be used as parity bit
bit 2
FERR: Framing Error bit
1 = Framing error (Can be updated by reading RCREG register and receive next valid byte)
0 = No framing error
bit 1
OERR: Overrun Error bit
1 = Overrun error (Can be cleared by clearing bit CREN)
0 = No overrun error
bit 0
RX9D: 9th bit of Received Data. Can be Address/Data bit or a parity bit.
Legend:
DS39541A-page 178
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
16.1
USART Baud Rate Generator
(BRG)
The BRG supports both the Asynchronous and Synchronous modes of the USART. It is a dedicated 8-bit
baud rate generator. The SPBRG register controls the
period of a free running 8-bit timer. In Asynchronous
mode, bit BRGH (TXSTA register) also controls the
baud rate. In Synchronous mode, bit BRGH is ignored.
Table 16-1 shows the formula for computation of the
baud rate for different USART modes, which only apply
in Master mode (internal clock).
Given the desired baud rate and FOSC, the nearest
integer value for the SPBRG register can be calculated
using the formula in Table 16-1. From this, the error in
baud rate can be determined.
Example 16-1 shows the calculation of the baud rate
error for the following conditions:
FOSC = 16 MHz
Desired Baud Rate = 9600
BRGH = 0
SYNC = 0
It may be advantageous to use the high baud rate
(BRGH = 1), even for slower baud clocks. This is
because the FOSC/(16(X + 1)) equation can reduce the
baud rate error in some cases.
Writing a new value to the SPBRG register causes the
BRG timer to be reset (or cleared). This ensures the
BRG does not wait for a timer overflow before outputting the new baud rate.
16.1.1
SAMPLING
The data on the RC7/RX/DT pin is sampled three times
by a majority detect circuit to determine if a high or a
low level is present at the RX pin.
EXAMPLE 16-1:
Desired Baud Rate
CALCULATING BAUD RATE ERROR
=
FOSC / (64 (X + 1))
X
X
X
=
=
=
( (FOSC / Desired Baud Rate) / 64 ) - 1
((16000000 / 9600) / 64) - 1
[25.042] = 25
Calculated Baud Rate
=
=
16000000 / (64 (25 + 1))
9615
Error
=
(Calculated Baud Rate - Desired Baud Rate)
Desired Baud Rate
(9615 - 9600) / 9600
0.16%
Solving for X:
=
=
TABLE 16-1:
BAUD RATE FORMULA
SYNC
BRGH = 0 (Low Speed)
BRGH = 1 (High Speed)
0
1
(Asynchronous) Baud Rate = FOSC/(64(X+1))
(Synchronous) Baud Rate = FOSC/(4(X+1))
Baud Rate = FOSC/(16(X+1))
NA
Legend: X = value in SPBRG (0 to 255)
TABLE 16-2:
REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on all
other
RESETS
TXSTA
CSRC
TX9
TXEN
SYNC
—
BRGH
TRMT
TX9D
0000 -010
0000 -010
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
0000 000x
0000 0000
0000 0000
SPBRG
Baud Rate Generator Register
Legend: x = unknown, - = unimplemented, read as '0'. Shaded cells are not used by the BRG.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 179
PIC18C601/801
TABLE 16-3:
BAUD RATES FOR SYNCHRONOUS MODE
FOSC =25 MHz
20 MHz
BAUD
RATE
(Kbps)
KBAUD
%
ERROR
SPBRG
value
(decimal)
0.3
NA
-
1.2
NA
-
2.4
NA
9.6
19.2
KBAUD
%
ERROR
SPBRG
value
(decimal)
-
NA
-
-
-
NA
-
-
-
-
NA
-
-
NA
-
-
NA
-
-
NA
-
-
NA
-
-
76.8
77.16
+0.47
80
76.92
+0.16
64
96
96.15
+0.16
64
96.15
+0.16
51
300
297.62
-0.79
20
294.12
-1.96
16
500
480.77
-3.85
12
500
0
9
HIGH
6250
-
0
5000
-
0
LOW
24.41
-
255
19.53
-
255
FOSC = 16 MHz
10 MHz
BAUD
RATE
(Kbps)
KBAUD
%
ERROR
SPBRG
value
(decimal)
0.3
NA
-
1.2
NA
-
2.4
NA
9.6
NA
7.15909 MHz
KBAUD
%
ERROR
SPBRG
value
(decimal)
-
NA
-
-
NA
-
-
-
NA
-
-
5.0688 MHz
KBAUD
%
ERROR
SPBRG
value
(decimal)
KBAUD
%
ERROR
SPBRG
value
(decimal)
-
NA
-
-
NA
-
-
NA
-
-
-
NA
-
-
-
NA
-
-
-
NA
-
NA
-
-
-
9.62
+0.23
185
9.60
0
131
19.2
19.23
+0.16
207
19.23
+0.16
129
19.24
+0.23
92
19.20
0
65
76.8
76.92
+0.16
51
75.76
-1.36
32
77.82
+1.32
22
74.54
-2.94
16
96
95.24
-0.79
41
96.15
+0.16
25
94.20
-1.88
18
97.48
+1.54
12
300
307.70
+2.56
12
312.50
+4.17
7
298.35
-0.57
5
NA
-
-
500
500
0
7
500
0
4
NA
-
-
NA
-
-
HIGH
4000
-
0
2500
-
0
1789.80
-
0
1267.20
-
0
LOW
15.63
-
255
9.77
-
255
6.99
-
255
4.95
-
255
FOSC = 4 MHz
BAUD
RATE
(Kbps)
3.579545 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
0.3
NA
-
1.2
NA
-
-
2.4
NA
-
9.6
9.62
19.2
76.8
1 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
NA
-
NA
-
NA
-
-
1.20
+0.16
207
-
NA
-
-
2.40
+0.16
+0.16
103
9.62
+0.23
92
9.62
19.23
+0.16
51
19.04
-0.83
46
76.92
+0.16
12
74.57
-2.90
11
SPBRG
value
(decimal)
KBAUD
%
ERROR
0.30
+1.14
1.17
-2.48
103
NA
-
-
+0.16
25
NA
-
-
19.23
+0.16
12
NA
-
-
NA
-
-
NA
-
-
KBAUD
%
ERROR
32.768 kHz
SPBRG
value
(decimal)
6
96
1000
+4.17
9
99.43
+3.57
8
NA
-
-
NA
-
300
NA
-
-
298.30
-0.57
2
NA
-
-
NA
-
-
500
500
0
1
NA
-
-
NA
-
-
NA
-
-
HIGH
1000
-
0
894.89
-
0
250
-
0
8.20
-
0
LOW
3.91
-
255
3.50
-
255
0.98
-
255
0.03
-
255
DS39541A-page 180
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 16-4:
BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 0)
FOSC = 25 MHz
BAUD
RATE
(Kbps)
%
ERROR
KBAUD
20 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
SPBRG
value
(decimal)
0.3
NA
-
NA
-
1.2
NA
-
-
NA
-
-
2.4
2.40
-0.15
162
2.40
+0.16
129
9.6
9.53
-0.76
40
9.47
-1.36
32
19.2
19.53
+1.73
19
19.53
+1.73
15
76.8
78.13
+1.73
4
78.13
+1.73
3
96
97.66
+1.73
3
NA
-
-
300
NA
-
-
312.50
+4.17
0
500
NA
-
-
NA
-
-
HIGH
390.63
-
0
312.50
-
0
LOW
1.53
-
255
1.22
-
255
FOSC = 16 MHz
BAUD
RATE
(Kbps)
KBAUD
%
ERROR
10 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
7.15909 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
5.0688 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
SPBRG
value
(decimal)
0.3
NA
-
NA
-
NA
-
NA
-
1.2
1.20
+0.16
207
1.20
+0.16
129
1.20
+0.23
92
1.20
0
65
2.4
2.40
+0.16
103
2.40
+0.16
64
2.38
-0.83
46
2.40
0
32
9.6
9.62
+0.16
25
9.77
+1.73
15
9.32
-2.90
11
9.90
+3.13
7
19.2
19.23
+0.16
12
19.53
+1.73
7
18.64
-2.90
5
19.80
+3.13
3
76.8
NA
-
-
78.13
+1.73
1
NA
-
-
79.20
+3.13
0
96
NA
-
-
NA
-
-
NA
-
-
NA
-
-
300
NA
-
-
NA
-
-
NA
-
-
NA
-
-
500
NA
-
-
NA
-
-
NA
-
-
NA
-
-
HIGH
250
-
0
156.25
-
0
111.86
-
0
79.20
-
0
LOW
0.98
-
255
0.61
-
255
0.44
-
255
0.31
-
255
FOSC = 4 MHz
BAUD
RATE
(Kbps)
KBAUD
%
ERROR
3.579545 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
1 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
32.768 kHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
SPBRG
value
(decimal)
0.3
0.30
-0.16
0.30
+0.23
0.30
+0.16
NA
-
1.2
1.20
+1.67
51
1.19
-0.83
46
1.20
+0.16
12
NA
-
-
2.4
2.40
+1.67
25
2.43
+1.32
22
NA
-
-
NA
-
-
9.6
NA
-
-
9.32
-2.90
5
NA
-
-
NA
-
-
19.2
NA
-
-
18.64
-2.90
2
NA
-
-
NA
-
-
76.8
NA
-
-
NA
-
-
NA
-
-
NA
-
-
96
NA
-
-
NA
-
-
NA
-
-
NA
-
-
300
NA
-
-
NA
-
-
NA
-
-
NA
-
-
500
NA
-
-
NA
-
-
NA
-
-
NA
-
-
HIGH
62.50
-
0
55.93
-
0
15.63
-
0
0.51
-
0
LOW
0.24
-
255
0.22
-
255
0.06
-
255
0.002
-
255
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 181
PIC18C601/801
TABLE 16-5:
BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 1)
FOSC = 25 MHz
BAUD
RATE
(Kbps)
KBAUD
%
ERROR
0.3
NA
-
1.2
NA
-
2.4
NA
-
9.6
9.59
19.2
76.8
20 MHz
SPBRG
value
(decimal)
SPBRG
value
(decimal)
KBAUD
%
ERROR
NA
-
-
NA
-
-
NA
-
-
-0.15
162
9.62
+0.16
129
19.30
+0.47
80
19.23
+0.16
64
78.13
+1.73
19
78.13
+1.73
15
96
97.66
+1.73
15
96.15
+0.16
12
300
312.50
+4.17
4
312.50
+4.17
3
500
520.83
+4.17
2
NA
-
-
HIGH
1562.50
-
0
1250
-
0
LOW
6.10
-
255
4.88
-
255
FOSC = 16 MHz
-
10 MHz
BAUD
RATE
(Kbps)
KBAUD
%
ERROR
0.3
NA
-
1.2
NA
-
-
2.4
NA
-
-
SPBRG
value
(decimal)
7.15909 MHz
SPBRG
value
(decimal)
5.0688 MHz
SPBRG
value
(decimal)
SPBRG
value
(decimal)
KBAUD
%
ERROR
NA
-
NA
-
NA
-
NA
-
-
NA
-
-
NA
-
-
NA
-
-
2.41
+0.23
185
2.40
0
131
KBAUD
%
ERROR
KBAUD
%
ERROR
9.6
9.62
+0.16
103
9.62
+0.16
64
9.52
-0.83
46
9.60
0
32
19.2
19.23
+0.16
51
18.94
-1.36
32
19.45
+1.32
22
18.64
-2.94
16
76.8
76.92
+0.16
12
78.13
+1.73
7
74.57
-2.90
5
79.20
+3.13
3
96
100
+4.17
9
NA
-
-
NA
-
-
NA
-
-
300
NA
-
-
312.50
+4.17
1
NA
-
-
NA
-
-
500
500
0
1
NA
-
-
NA
-
-
NA
-
-
HIGH
1000
-
0
625
-
0
447.44
-
0
316.80
-
0
LOW
3.91
-
255
2.44
-
255
1.75
-
255
1.24
-
255
FOSC = 4 MHz
BAUD
RATE
(Kbps)
KBAUD
%
ERROR
3.579545 MHz
SPBRG
value
(decimal)
KBAUD
%
ERROR
1 MHz
SPBRG
value
(decimal)
32.768 kHz
KBAUD
%
ERROR
SPBRG
value
(decimal)
KBAUD
%
ERROR
SPBRG
value
(decimal)
6
0.3
NA
-
-
NA
-
-
0.30
+0.16
207
0.29
-2.48
1.2
1.20
+0.16
207
1.20
+0.23
185
1.20
+0.16
51
NA
-
-
2.4
2.40
+0.16
103
2.41
+0.23
92
2.40
+0.16
25
NA
-
-
9.6
9.62
+0.16
25
9.73
+1.32
22
NA
-
-
NA
-
-
19.2
19.23
+0.16
12
18.64
-2.90
11
NA
-
-
NA
-
-
76.8
NA
-
-
74.57
-2.90
2
NA
-
-
NA
-
-
96
NA
-
-
NA
-
-
NA
-
-
NA
-
-
300
NA
-
-
NA
-
-
NA
-
-
NA
-
-
500
NA
-
-
NA
-
-
NA
-
-
NA
-
-
HIGH
250
-
0
55.93
-
0
62.50
-
0
2.05
-
0
LOW
0.98
-
255
0.22
-
255
0.24
-
255
0.008
-
255
DS39541A-page 182
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
16.2
USART Asynchronous Mode
Once the TXREG register transfers the data to the TSR
register (occurs in one TCY), the TXREG register is
empty and flag bit TXIF (PIR registers) is set. This interrupt can be enabled/disabled by setting/clearing
enable bit TXIE (PIE registers). Flag bit TXIF will be
set, regardless of the state of enable bit TXIE and cannot be cleared in software. It will reset only when new
data is loaded into the TXREG register. While flag bit
TXIF indicated the status of the TXREG register,
another bit TRMT (TXSTA register) shows the status of
the TSR register. Status bit TRMT is a read only bit,
which is set when the TSR register is empty. No interrupt logic is tied to this bit, so the user has to poll this
bit in order to determine if the TSR register is empty.
In this mode, data is transmitted in non-return-to-zero
(NRZ) format. Data consists of one START bit, eight or
nine data bits and one STOP bit. Data is transmitted in
serial fashion with LSb first. An on-chip 8-bit baud rate
generator can be programmed to generate the desired
baud rate. The baud rate generator produces a clock,
either x16 or x64 of the bit shift rate, depending on the
BRGH bit (TXSTA register). USART does not automatically calculate the parity bit for the given data byte. If
parity is to be transmitted, USART must be programmed to transmit nine bits and software must set/
clear ninth data bit as parity bit. Asynchronous mode is
stopped during SLEEP.
Note 1: The TSR register is not mapped in data
memory, so it is not available to the user.
Asynchronous mode is selected by clearing the SYNC
bit (TXSTA register).
2: Flag bit TXIF is set when enable bit TXEN
is set.
The USART Asynchronous module consists of the following important elements:
•
•
•
•
Steps to follow when setting up an Asynchronous
Transmission:
Baud Rate Generator
Sampling Circuit
Asynchronous Transmitter
Asynchronous Receiver
16.2.1
1.
2.
USART ASYNCHRONOUS
TRANSMITTER
3.
4.
The USART transmitter block diagram is shown in
Figure 16-1. The heart of the transmitter is the Transmit
(serial) Shift Register (TSR). The TSR register obtains
its data from the Read/Write Transmit Buffer register
(TXREG). The TXREG register is loaded with data in
software. The TSR register is not loaded until the STOP
bit has been transmitted from the previous load. As
soon as the STOP bit is transmitted, the TSR is loaded
with new data from the TXREG register (if available).
FIGURE 16-1:
5.
6.
7.
Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is desired,
set bit BRGH (Section 16.1).
Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
If interrupts are desired, set enable bit TXIE.
If 9-bit transmission is desired, set transmit bit
TX9. Can be used as address/data bit.
Enable the transmission by setting bit TXEN,
which will also set bit TXIF.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
Load data to the TXREG register (starts transmission).
USART TRANSMIT BLOCK DIAGRAM
Data Bus
TXIF
TXREG Register
TXIE
8
MSb
LSb
• • •
(8)
Pin Buffer
and Control
0
TSR Register
RC6/TX/CK pin
Interrupt
TXEN
Baud Rate CLK
TRMT
SPEN
SPBRG
TX9
Baud Rate Generator
TX9D
Note:
I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 183
PIC18C601/801
FIGURE 16-2:
ASYNCHRONOUS TRANSMISSION
Write to TXREG
Word 1
BRG Output
(Shift Clock)
RC6/TX/CK (pin)
START Bit
Bit 0
Bit 1
TXIF bit
(Transmit Buffer
Register Empty Flag)
TRMT bit
(Transmit Shift
Register Empty Flag)
FIGURE 16-3:
Bit 7/8
STOP Bit
Word 1
Word 1
Transmit Shift Reg
ASYNCHRONOUS TRANSMISSION (BACK TO BACK)
Write to TXREG
Word 2
Word 1
BRG Output
(Shift Clock)
RC6/TX/CK (pin)
START Bit
Bit 0
Bit 1
Word 1
TXIF bit
(Interrupt Reg. Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Bit 7/8
STOP Bit
START Bit
Bit 0
Word 2
Word 1
Transmit Shift Reg.
Word 2
Transmit Shift Reg.
Note: This timing diagram shows two consecutive transmissions.
TABLE 16-6:
Name
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Bit 7
Bit 6
Bit 5
Bit 4
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE
Bit 3
RBIE
Bit 2
Bit 1
TMR0IF INT0IF
Bit 0
Value on
POR,
BOR
Value on
all other
RESETS
RBIF
0000 000x
0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF CCP1IF TMR2IF TMR1IF
-000 0000
-000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE CCP1IE TMR2IE TMR1IE
-000 0000
-000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP CCP1IP TMR2IP TMR1IP
-000 0000
-000 0000
RCSTA
SPEN
RX9
SREN
CREN
0000 -00x
0000 -00x
0000 0000
0000 0000
0000 0010
0000 0010
0000 0000
0000 0000
—
FERR
OERR
RX9D
TXREG USART Transmit Register
TXSTA
CSRC
TX9
TXEN
SYNC ADDEN BRGH
TRMT
SPBRG Baud Rate Generator Register
TX9D
Legend: x = unknown, - = unimplemented locations read as '0'.
Shaded cells are not used for Asynchronous Transmission.
DS39541A-page 184
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
16.2.2
USART ASYNCHRONOUS
RECEIVER
16.2.3
The receiver block diagram is shown in Figure 16-4.
The data is received on the RC7/RX/DT pin and drives
the data recovery block. The data recovery block is
actually a high speed shifter, operating at x16 times the
baud rate, whereas the main receive serial shifter operates at the bit rate or at FOSC. This mode would typically be used in RS-232 systems.
This mode would typically be used in RS-485 systems.
Steps to follow when setting up an Asynchronous
Reception with Address Detect Enable:
1.
Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is required,
set the BRGH bit.
2. Enable the asynchronous serial port by clearing
the SYNC bit and setting the SPEN bit.
3. If interrupts are required, set the RCEN bit and
select the desired priority level with the RCIP bit.
4. Set the RX9 bit to enable 9-bit reception.
5. Set the ADDEN bit to enable address detect.
6. Enable reception by setting the CREN bit.
7. The RCIF bit will be set when reception is complete. The interrupt will be acknowledged if the
RCIE and GIE bits are set.
8. Read the RCSTA register to determine if any
error occurred during reception, as well as read
bit 9 of data (if applicable).
9. Read RCREG to determine if the device is being
addressed.
10. If any error occurred, clear the CREN bit.
11. If the device has been addressed, clear the
ADDEN bit to allow all received data into the
receive buffer and interrupt the CPU.
Steps to follow when setting up an Asynchronous
Reception:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is desired,
set bit BRGH (Section 16.1).
Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
If interrupts are desired, set enable bit RCIE.
If 9-bit reception is desired, set bit RX9.
Enable the reception by setting bit CREN.
Flag bit RCIF will be set when reception is complete and an interrupt will be generated if enable
bit RCIE was set.
Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
Read the 8-bit received data by reading the
RCREG register.
If any error occurred, clear the error by clearing
enable bit CREN.
FIGURE 16-4:
SETTING UP 9-BIT MODE WITH
ADDRESS DETECT
USART RECEIVE BLOCK DIAGRAM
x64 Baud Rate CLK
FERR
OERR
CREN
SPBRG
÷ 64
or
÷ 16
Baud Rate Generator
RSR Register
MSb
STOP (8)
7
• • •
1
LSb
0 START
RC7/RX/DT
Pin Buffer
and Control
Data
Recovery
RX9
RX9D
SPEN
RCREG Register
FIFO
8
Interrupt
RCIF
Data Bus
RCIE
Note:
I/O pins have diode protection to VDD and VSS.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 185
PIC18C601/801
FIGURE 16-5:
ASYNCHRONOUS RECEPTION
START
bit
bit0
RX (pin)
bit1
bit7/8 STOP
bit
Rcv Shift
Reg
Rcv Buffer Reg
START
bit0
bit
bit7/8 STOP
bit
bit7/8
STOP
bit
Word 2
RCREG
Word 1
RCREG
Read Rcv
Buffer Reg
RCREG
START
bit
RCIF
(Interrupt Flag)
OERR bit
CREN
Note: This timing diagram shows three words appearing on the RX input. The RCREG (receive buffer) is read after the third word,
causing the OERR (overrun) bit to be set.
TABLE 16-7:
Name
INTCON
REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Bit 7
Bit 6
Bit 5
GIE/GIEH PEIE/GIEL TMR0IE
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on
all other
RESETS
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x
0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF TMR2IF
TMR1IF
-000 0000
-000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE TMR2IE TMR1IE
-000 0000
-000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP TMR2IP TMR1IP
-000 0000
-000 0000
RCSTA
SPEN
RX9
SREN
CREN
—
FERR
OERR
RX9D
0000 -00x
0000 -00x
0000 0000
0000 0000
TXEN
SYNC
ADDEN
BRGH
TRMT
TX9D
0000 0010
0000 0010
0000 0000
0000 0000
RCREG
TXSTA
SPBRG
USART Receive Register
CSRC
TX9
Baud Rate Generator Register
Legend: x = unknown, - = unimplemented locations read as '0'. Shaded cells are not used for Asynchronous Reception.
DS39541A-page 186
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
16.3
USART Synchronous Master
Mode
bit TXIF (PIR registers) is set. The interrupt can be
enabled/disabled by setting/clearing enable bit TXIE
(PIE registers). Flag bit TXIF will be set, regardless of
the state of enable bit TXIE, and cannot be cleared in
software. It will reset only when new data is loaded into
the TXREG register. While flag bit TXIF indicates the
status of the TXREG register, another bit TRMT
(TXSTA register) shows the status of the TSR register.
TRMT is a read only bit, which is set when the TSR is
empty. No interrupt logic is tied to this bit, so the user
has to poll this bit in order to determine if the TSR register is empty. The TSR is not mapped in data memory,
so it is not available to the user.
In Synchronous Master mode, the data is transmitted in
a half-duplex manner (i.e., transmission and reception
do not occur at the same time). When transmitting data,
the reception is inhibited and vice versa. Synchronous
mode is entered by setting bit SYNC (TXSTA register).
In addition, enable bit SPEN (RCSTA register) is set, in
order to configure the RC6/TX/CK and RC7/RX/DT I/O
pins to CK (clock) and DT (data) lines, respectively. The
Master mode indicates that the processor transmits the
master clock on the CK line. The Master mode is
entered by setting bit CSRC (TXSTA register).
16.3.1
Steps to follow when setting up a Synchronous Master
Transmission:
USART SYNCHRONOUS MASTER
TRANSMISSION
1.
The USART transmitter block diagram is shown in
Figure 16-1. The heart of the transmitter is the Transmit
(serial) Shift register (TSR). The shift register obtains
its data from the Read/Write Transmit Buffer register
(TXREG). The TXREG register is loaded with data in
software. The TSR register is not loaded until the last
bit has been transmitted from the previous load. As
soon as the last bit is transmitted, the TSR is loaded
with new data from the TXREG (if available). Once the
TXREG register transfers the data to the TSR register
(occurs in one TCY), the TXREG is empty and interrupt
TABLE 16-8:
Bit 7
Bit 6
Bit 5
Bit 4
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
PIR1
—
ADIF
RCIF
PIE1
—
ADIE
RCIE
IPR1
—
ADIP
RCSTA
SPEN
RX9
TXSTA
SPBRG
3.
4.
5.
6.
7.
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER TRANSMISSION
Name
TXREG
2.
Initialize the SPBRG register for the appropriate
baud rate (Section 16.1).
Enable the synchronous master serial port by
setting bits SYNC, SPEN, and CSRC.
If interrupts are desired, set enable bit TXIE.
If 9-bit transmission is desired, set bit TX9.
Enable the transmission by setting bit TXEN.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
Start transmission by loading data to the TXREG
register.
Bit 0
Value on
POR,
BOR
Value on all
other
RESETS
INT0IF
RBIF
0000 000x
0000 000u
TMR2IF
TMR1IF
-000 0000
-000 0000
TMR2IE
TMR1IE
-000 0000
-000 0000
CCP1IP
TMR2IP
TMR1IP
-000 0000
-000 0000
FERR
OERR
RX9D
0000 -00x
0000 -00x
0000 0000
0000 0000
0000 0010
0000 0010
0000 0000
0000 0000
Bit 3
Bit 2
INT0IE
RBIE
TMR0IF
TXIF
SSPIF
CCP1IF
TXIE
SSPIE
CCP1IE
RCIP
TXIP
SSPIP
SREN
CREN
—
Bit 1
USART Transmit Register
CSRC
TX9
TXEN
SYNC
ADDEN
BRGH
TRMT
Baud Rate Generator Register
TX9D
Legend: x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Master Transmission.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 187
PIC18C601/801
FIGURE 16-6:
SYNCHRONOUS TRANSMISSION
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
RC7/RX/DT
pin
Bit 0
Bit 1
Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Bit 2
Bit 7
Word 1
Bit 0
Bit 1
Word 2
Bit 7
RC6/TX/CK
pin
Write to
TXREG Reg
Write Word 1
Write Word 2
TXIF bit
(Interrupt Flag)
TRMT bit TRMT
TXEN bit
’1’
’1’
Note: Sync Master mode; SPBRG = ’0’; continuous transmission of two 8-bit words.
FIGURE 16-7:
SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
RC7/RX/DT pin
bit0
bit1
bit2
bit6
bit7
RC6/TX/CK pin
Write to
TXREG reg
TXIF bit
TRMT bit
TXEN bit
DS39541A-page 188
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
16.3.2
USART SYNCHRONOUS MASTER
RECEPTION
3.
4.
5.
6.
Ensure bits CREN and SREN are clear.
If interrupts are desired, set enable bit RCIE.
If 9-bit reception is desired, set bit RX9.
If a single reception is required, set bit SREN.
For continuous reception, set bit CREN.
7. Interrupt flag bit RCIF will be set when reception
is complete and an interrupt will be generated if
the enable bit RCIE was set.
8. Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
9. Read the 8-bit received data by reading the
RCREG register.
10. If any error occurred, clear the error by clearing
bit CREN.
Once Synchronous Master mode is selected, reception
is enabled by setting either enable bit SREN (RCSTA
register), or enable bit CREN (RCSTA register). Data is
sampled on the RC7/RX/DT pin on the falling edge of
the clock. If enable bit SREN is set, only a single word
is received. If enable bit CREN is set, the reception is
continuous until CREN is cleared. If both bits are set,
then CREN takes precedence.
When setting up a Synchronous Master reception, follow these steps:
1.
2.
Initialize the SPBRG register for the appropriate
baud rate (Section 16.1).
Enable the synchronous master serial port by
setting bits SYNC, SPEN and CSRC.
TABLE 16-9:
Name
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
Bit 7
Bit 6
INTCON GIE/GIEH PEIE/GIEL
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on all
other
RESETS
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x
0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000
-000 0000
RCSTA
SPEN
RX9
SREN
CREN
—
FERR
OERR
RX9D
0000 -00x
0000 -00x
0000 0000
0000 0000
0000 0010
0000 0010
0000 0000
0000 0000
RCREG USART Receive Register
TXSTA
SPBRG
CSRC
TX9
TXEN
SYNC
ADDEN
BRGH
TRMT
TX9D
Baud Rate Generator Register
Legend: x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Master Reception.
FIGURE 16-8:
SYNCHRONOUS RECEPTION (MASTER MODE, SREN)
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
RC7/RX/DT pin
bit0
bit1
bit2
bit3
bit4
bit5
bit6
bit7
RC6/TX/CK pin
Write to
bit SREN
SREN bit
CREN bit
’0’
’0’
RCIF bit
(interrupt)
Read
RXREG
Note: Timing diagram demonstrates SYNC Master mode with bit SREN = ’1’ and bit BRGH = ’0’.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 189
PIC18C601/801
16.4
16.4.2
USART Synchronous Slave Mode
Synchronous Slave mode differs from the Master
mode, in that the shift clock is supplied externally at the
RC6/TX/CK pin (instead of being supplied internally in
Master mode). This allows the device to transfer or
receive data while in SLEEP mode. Slave mode is
entered by clearing bit CSRC (TXSTA register).
USART SYNCHRONOUS SLAVE
RECEPTION
The operation of the Synchronous Master and Slave
modes is identical, except in the case of the SLEEP
mode and bit SREN, which is a "don’t care" in Slave
mode.
The operation of the Synchronous Master and Slave
modes are identical, except in the case of the SLEEP
mode.
If receive is enabled by setting bit CREN prior to the
SLEEP instruction, then a word may be received during
SLEEP. On completely receiving the word, the RSR
register will transfer the data to the RCREG register,
and if enable bit RCIE bit is set, the interrupt generated
will wake the chip from SLEEP. If the global interrupt is
enabled, the program will branch to the interrupt vector.
If two words are written to the TXREG and then the
SLEEP instruction is executed, the following will occur:
When setting up a Synchronous Slave Reception,
follow these steps:
a)
1.
16.4.1
b)
c)
d)
e)
USART SYNCHRONOUS SLAVE
TRANSMIT
The first word will immediately transfer to the
TSR register and transmit.
The second word will remain in TXREG register.
Flag bit TXIF will not be set.
When the first word has been shifted out of TSR,
the TXREG register will transfer the second
word to the TSR and flag bit TXIF will be set.
If enable bit TXIE is set, the interrupt will wake the
chip from SLEEP. If the global interrupt is enabled,
the program will branch to the interrupt vector.
2.
3.
4.
5.
6.
When setting up a Synchronous Slave Transmission,
follow these steps:
1.
2.
3.
4.
5.
6.
7.
7.
Enable the synchronous slave serial port by setting bits SYNC and SPEN and clearing bit CSRC.
Clear bits CREN and SREN.
If interrupts are desired, set enable bit TXIE.
If 9-bit transmission is desired, set bit TX9.
Enable the transmission by setting enable bit
TXEN.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
Start transmission by loading data to the TXREG
register.
8.
Enable the synchronous master serial port by
setting bits SYNC and SPEN and clearing bit
CSRC.
If interrupts are desired, set enable bit RCIE.
If 9-bit reception is desired, set bit RX9.
To enable reception, set enable bit CREN.
Flag bit RCIF will be set when reception is complete. An interrupt will be generated if enable bit
RCIE was set.
Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
Read the 8-bit received data by reading the
RCREG register.
If any error occurred, clear the error by clearing
bit CREN.
TABLE 16-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION
Name
INTCON
Bit 7
Bit 6
Bit 5
GIE/GIEH PEIE/GIEL TMR0IE
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on all
other
RESETS
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x
0000 000u
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000
-000 0000
SPEN
RX9
SREN
CREN
—
FERR
OERR
RX9D
0000 -00x
0000 -00x
0000 0000
0000 0000
0000 0010
0000 0010
0000 0000
0000 0000
PIR1
RCSTA
TXREG
TXSTA
SPBRG
USART Transmit Register
CSRC
TX9
TXEN
SYNC
ADDEN
BRGH
TRMT
Baud Rate Generator Register
TX9D
Legend: x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Slave Transmission.
DS39541A-page 190
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 16-11: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION
Name
INTCON
Bit 7
Bit 6
Bit 5
GIE/GIEH PEIE/GIEL TMR0IE
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
Value on all
other
RESETS
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x
0000 000u
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000
-000 0000
RCSTA
SPEN
RX9
SREN
CREN
—
FERR
OERR
RX9D
0000 -00x
0000 -00x
0000 0000
0000 0000
0000 0010
0000 0010
0000 0000
0000 0000
RCREG
TXSTA
SPBRG
USART Receive Register
CSRC
TX9
TXEN
SYNC
ADDEN
BRGH
TRMT
Baud Rate Generator Register
TX9D
Legend: x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Slave Reception.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 191
PIC18C601/801
NOTES:
DS39541A-page 192
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
17.0
10-BIT ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
The A/D module has five registers:
The analog-to-digital (A/D) converter module has 8
inputs for the PIC18C601 devices and 12 for the
PIC18C801 devices. This module has the ADCON0,
ADCON1, and ADCON2 registers.
The A/D allows conversion of an analog input signal
to a corresponding 10-bit digital number.
REGISTER 17-1:
•
•
•
•
•
A/D Result High Register (ADRESH)
A/D Result Low Register (ADRESL)
A/D Control Register 0 (ADCON0)
A/D Control Register 1 (ADCON1)
A/D Control Register 2 (ADCON2)
The ADCON0 register, shown in Register 17-1, controls
the operation of the A/D module. The ADCON1 register,
shown in Register 17-2, configures the functions of the
port pins. The ADCON2, shown in Register 16-3, configures the A/D clock source and justification.
ADCON0 REGISTER
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
bit 7
bit 0
bit 7-6
Unimplemented: Read as '0'
bit 5-2
CHS3:CHS0: Analog Channel Select bits
0000 = channel 00, (AN0)
0001 = channel 01, (AN1)
0010 = channel 02, (AN2)
0011 = channel 03, (AN3)
0100 = channel 04, (AN4)
0101 = channel 05, (AN5)
0110 = channel 06, (AN6)
0111 = channel 07, (AN7)
1000 = channel 08, (AN8)(1)
1001 = channel 09, (AN9)(1)
1010 = channel 10, (AN10)(1)
1011 = channel 11, (AN11)(1)
1100 = Reserved
1101 = Reserved
1110 = Reserved
1111 = Reserved
These channels are not available on the PIC18C601 devices.
bit 1
GO/DONE: A/D Conversion Status bit
When ADON = 1:
1 = A/D conversion in progress. Setting this bit starts an A/D conversion cycle. This bit is
automatically cleared by hardware when the A/D conversion is complete.
0 = A/D conversion not in progress
bit 0
ADON: A/D On bit
1 = A/D converter module is operating
0 = A/D converter module is shut-off and consumes no operating current
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
 2001 Microchip Technology Inc.
Advance Information
x = Bit is unknown
DS39541A-page 193
PIC18C601/801
REGISTER 17-2:
ADCON1 REGISTER
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
bit 7
bit 0
bit 7-6
Unimplemented: Read as '0'
bit 5-4
VCFG1:VCFG0: Voltage Reference Configuration bits
bit 3-0
A/D VREF+
A/D VREF-
00
AVDD
AVSS
01
External VREF+
AVSS
10
AVDD
External VREF-
11
External VREF+
External VREF-
PCFG3:PCFG0: A/D Port Configuration Control bits
AN9
AN8
AN7
AN6
AN5
AN4
0000
AN11 AN10
A
A
A
A
A
A
A
A
AN3 AN2 AN1 AN0
A
A
A
A
0001
A
A
A
A
A
A
A
A
A
A
A
A
0010
A
A
A
A
A
A
A
A
A
A
A
A
0011
A
A
A
A
A
A
A
A
A
A
A
A
0100
D
A
A
A
A
A
A
A
A
A
A
A
0101
D
D
A
A
A
A
A
A
A
A
A
A
0110
D
D
D
A
A
A
A
A
A
A
A
A
0111
D
D
D
D
A
A
A
A
A
A
A
A
1000
D
D
D
D
D
A
A
A
A
A
A
A
1001
D
D
D
D
D
D
A
A
A
A
A
A
1010
D
D
D
D
D
D
D
A
A
A
A
A
1011
D
D
D
D
D
D
D
D
A
A
A
A
1100
D
D
D
D
D
D
D
D
D
A
A
A
1101
D
D
D
D
D
D
D
D
D
D
A
A
1110
D
D
D
D
D
D
D
D
D
D
D
A
1111
D
D
D
D
D
D
D
D
D
D
D
D
A = Analog input
D = Digital I/O
Shaded cells = Additional A/D channels available on PIC18C801 devices.
Legend:
DS39541A-page 194
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 17-3:
ADCON2 REGISTER
R/W-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
ADFM
—
—
—
—
ADCS2
ADCS1
ADCS0
bit 7
bit 7
bit 0
ADFM: A/D Result Format Select bit
1 = Right justified
0 = Left justified
bit 6-3
Unimplemented: Read as '0'
bit 2-0
ADCS2:ADCS0: A/D Conversion Clock Select bits
000 = FOSC/2
001 = FOSC/8
010 = FOSC/32
011 = FRC (clock derived from an internal RC oscillator = 1 MHz max)
100 = FOSC/4
101 = FOSC/16
110 = FOSC/64
111 = FRC (clock derived from an internal RC oscillator = 1 MHz max)
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
The analog reference voltage is software selectable to
either the device’s positive and negative supply
voltage (VDD and VSS), or the voltage level on the
RA3/AN3/VREF+ pin and RA2/AN2/VREF-.
The A/D converter has a unique feature of being able
to operate while the device is in SLEEP mode. To operate in SLEEP, the A/D conversion clock must be
derived from the A/D’s internal RC oscillator.
The output of the sample and hold is the input into the
converter, which generates the result via successive
approximation.
x = Bit is unknown
Each port pin associated with the A/D converter can
be configured as an analog input (RA3 can also be a
voltage reference), or as a digital I/O.
The ADRESH and ADRESL registers contain the
result of the A/D conversion. When the A/D conversion is complete, the result is loaded into the
ADRESH/ADRESL registers, the GO/DONE bit
(ADCON0 register) is cleared, and A/D interrupt flag
bit ADIF is set. The block diagram of the A/D module
is shown in Figure 17-1.
A device RESET forces all registers to their RESET
state. This forces the A/D module to be turned off and
any conversion is aborted.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 195
PIC18C601/801
FIGURE 17-1:
A/D BLOCK DIAGRAM
CHS3:CHS0
0111
RF2/AN7
0110
RF1/AN6
0101
RF0/AN5
0100
RA5/AN4
0011
RA3/AN3/VREF+
0010
RA2/AN2/VREF0001
RA1/AN1
0000
VIN
RA0/AN0
(Input voltage)
A/D
Converter
AVDD
1011
RH7/AN11(1)
1010
RH6/AN10(1)
1001
RH5/AN9(1)
1000
RH4/AN8(1)
VREF+
(Reference
Voltage)
VCFG0
VREF(Reference
Voltage)
AVSS
VCFG1
Note 1: These channels are not available on the PIC18C601 devices.
DS39541A-page 196
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
The value in the ADRESH/ADRESL registers is not
modified for a Power-on Reset. The ADRESH/ADRESL
registers will contain unknown data after a Power-on
Reset.
2.
After the A/D module has been configured as desired,
the selected channel must be acquired before the conversion is started. The analog input channels must
have their corresponding TRIS bits selected as an
input. To determine acquisition time, see Section 17.1.
After this acquisition time has elapsed, the A/D conversion can be started. The following steps should be followed to do an A/D conversion:
3.
4.
1.
6.
5.
Configure the A/D module:
• Configure analog pins, voltage reference
and digital I/O (ADCON1)
• Select A/D input channel (ADCON0)
• Select A/D conversion clock (ADCON2)
• Turn on A/D module (ADCON0)
FIGURE 17-2:
7.
Configure A/D interrupt (if desired):
• Clear ADIF bit
• Set ADIE bit
• Set GIE bit
Wait the required acquisition time.
Start conversion:
• Set GO/DONE bit (ADCON0 register)
Wait for A/D conversion to complete, by either:
• Polling for the GO/DONE bit to be cleared,
OR
• Waiting for the A/D interrupt
Read A/D Result registers (ADRESH:ADRESL);
clear bit ADIF, if required.
For next conversion, go to step 1 or step 2, as
required. The A/D conversion time per bit is
defined as TAD. A minimum wait of 2TAD is
required before next acquisition starts.
ANALOG INPUT MODEL
VDD
Sampling
Switch
VT = 0.6 V
Rs
VAIN
RIC ≤ 1 k
ANx
CPIN
5 pF
VT = 0.6 V
SS
RSS
I leakage
± 500 nA
CHOLD = 120 pF
VSS
Legend: CPIN
= input capacitance
= threshold voltage
VT
I LEAKAGE = leakage current at the pin due to
various junctions
= interconnect resistance
RIC
= sampling switch
SS
= sample/hold capacitance (from DAC)
CHOLD
RSS
= sampling switch resistance
 2001 Microchip Technology Inc.
Advance Information
VDD
6V
5V
4V
3V
2V
5 6 7 8 9 10 11
Sampling Switch ( kΩ )
DS39541A-page 197
PIC18C601/801
17.1
A/D Acquisition Requirements
For the A/D converter to meet its specified accuracy,
the charge holding capacitor (CHOLD) must be allowed
to fully charge to the input channel voltage level. The
analog input model is shown in Figure 17-2. The
source impedance (RS) and the internal sampling
switch (RSS) impedance directly affect the time
required to charge the capacitor CHOLD. The sampling
switch (RSS) impedance varies over the device voltage
(VDD). The source impedance affects the offset voltage
at the analog input (due to pin leakage current). The
maximum recommended impedance for analog
sources is 2.5kΩ. After the analog input channel is
selected (changed), this acquisition must be done
before the conversion can be started.
Note:
Example 17-1 shows the calculation of the minimum
required acquisition time TACQ. This calculation is
based on the following application system assumptions:
CHOLD
Rs
Conversion Error
VDD
Temperature
VHOLD
=
=
≤
=
=
=
120 pF
2.5 kΩ
1/2 LSb
5V → Rss = 7 kΩ
50°C (system max.)
0V @ time = 0
When the conversion is started, the holding capacitor is disconnected from the
input pin.
EQUATION 17-1:
TACQ
To calculate the minimum acquisition time,
Equation 17-1 may be used. This equation assumes
that 1/2 LSb error is used (1024 steps for the A/D). The
1/2 LSb error is the maximum error allowed for the A/D
to meet its specified resolution.
ACQUISITION TIME
=
Amplifier Settling Time +
Holding Capacitor Charging Time +
Temperature Coefficient
=
TAMP + TC + TCOFF
EQUATION 17-2:
VHOLD
or
TC
A/D MINIMUM CHARGING TIME
=
(VREF - (VREF/2048)) • (1 - e(-Tc/CHOLD(RIC + RSS + RS)))
=
-(120 pF)(1 kΩ + RSS + RS) ln(1/2047)
EXAMPLE 17-1: CALCULATING THE MINIMUM REQUIRED ACQUISITION TIME
TACQ
=
TAMP + TC + TCOFF
Temperature coefficient is only required for temperatures > 25°C.
TACQ
=
2 µs + TC + [(Temp - 25°C)(0.05 µs/°C)]
TC
=
-CHOLD (RIC + RSS + RS) ln(1/2047)
-120 pF (1 kΩ + 7 kΩ + 2.5 kΩ) ln(0.0004885)
-120 pF (10.5 kΩ) ln(0.0004885)
-1.26 µs (-7.6241)
9.61 µs
TACQ
=
2 µs + 9.61 µs + [(50°C - 25°C)(0.05 µs/°C)]
11.61 µs + 1.25 µs
12.86 µs
DS39541A-page 198
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
17.2
Selecting the A/D Conversion
Clock
The A/D conversion time per bit is defined as TAD. The
A/D conversion requires 12 TAD per 10-bit conversion.
The source of the A/D conversion clock is software
selectable. There are seven possible options for TAD:
•
•
•
•
•
•
•
2TOSC
4TOSC
8TOSC
16TOSC
32TOSC
64TOSC
Internal RC oscillator
17.3
The ADCON1, TRISA, TRISF and TRISH registers
control the operation of the A/D port pins. The port pins
needed as analog inputs must have their corresponding TRIS bits set (input). If the TRIS bit is cleared (output), the digital output level (VOH or VOL) will be
converted.
The A/D operation is independent of the state of the
CHS3:CHS0 bits and the TRIS bits.
For correct A/D conversions, the A/D conversion clock
(TAD) must be selected to ensure a minimum TAD time
of 1.6 µs.
Note 1: When reading the port register, all pins
configured as analog input channels will
read as cleared (a low level). Pins configured as digital inputs will convert an analog input. Analog levels on a digitally
configured input will not affect the conversion accuracy.
2: Analog levels on any pin defined as a digital input may cause the input buffer to
consume current out of the device’s specification limits.
Table 17-1 shows the resultant TAD times derived from
the device operating frequencies and the A/D clock
source selected.
TABLE 17-1:
Configuring Analog Port Pins
TAD vs. DEVICE OPERATING FREQUENCIES
AD Clock Source (TAD)
Maximum Device Frequency
Operation
ADCS2:ADCS0
PIC18C601/801
PIC18LC601/801(5)
2TOSC
000
1.25 MHz
666 kHz
4TOSC
100
2.50 MHz
1.33 MHz
8TOSC
001
5.00 MHz
2.67 MHz
16TOSC
101
10.0 MHz
5.33 MHz
32TOSC
010
20.0 MHz
10.67 MHz
64TOSC
110
—
—
RC
x11
—
—
The RC source has a typical TAD time of 4 µs.
These values violate the minimum required TAD time.
For faster conversion times, the selection of another clock source is recommended.
For device frequencies above 1 MHz, the device must be in SLEEP for the entire conversion or the A/D
accuracy may be out of specification.
5: This column is for the LC devices only.
Note 1:
2:
3:
4:
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 199
PIC18C601/801
17.4
A/D Conversions
17.5
Figure 17-3 shows the operation of the A/D converter
after the GO bit has been set. Clearing the GO/DONE
bit during a conversion will abort the current conversion. The A/D result register pair will NOT be updated
with the partially completed A/D conversion sample.
That is, the ADRESH:ADRESL registers will continue
to contain the value of the last completed conversion
(or the last value written to the ADRESH:ADRESL registers). After the A/D conversion is aborted, a 2TAD wait
is required before the next acquisition is started. After
this 2TAD wait, acquisition on the selected channel is
automatically started.
Note:
The GO/DONE bit should NOT be set in
the same instruction that turns on the A/D.
FIGURE 17-3:
Use of the CCP2 Trigger
An A/D conversion can be started by the “special event
trigger” of the CCP2 module. This requires that the
CCP2M3:CCP2M0 bits (CCP2CON<3:0>) be programmed as 1011, and that the A/D module is enabled
(ADON bit is set). When the trigger occurs, the GO/DONE
bit will be set, starting the A/D conversion and the Timer1
(or Timer3) counter will be reset to zero. Timer1 (or
Timer3) is reset to automatically repeat the A/D acquisition period with minimal software overhead (moving
ADRESH/ADRESL to the desired location). The appropriate analog input channel must be selected and the minimum acquisition done before the “special event trigger”
sets the GO/DONE bit (starts a conversion).
If the A/D module is not enabled (ADON is cleared), the
“special event trigger” will be ignored by the A/D module, but will still reset the Timer1 (or Timer3) counter.
A/D CONVERSION TAD CYCLES
TCY - TAD TAD1 TAD2 TAD3 TAD4 TAD5 TAD6 TAD7 TAD8 TAD9 TAD10 TAD11
b9
b0
b9
b4
b2
b5
b3
b1
b6
b8
b7
Conversion Starts
Holding capacitor is disconnected from analog input (typically 100 ns)
Set GO bit
Next Q4: ADRESH/ADRESL is loaded, GO bit is cleared,
ADIF bit is set, holding capacitor is connected to analog input.
DS39541A-page 200
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 17-2:
SUMMARY OF A/D REGISTERS
Name
Bit 7
Bit 6
Bit 5
INTCON
GIE/GIEH
PIR1
—
ADIF
RCIF
PEIE/GIEL TMR0IE
Bit 4
Bit 3
Bit 2
INT0IE
RBIE
TMR0IF
TXIF
SSPIF
CCP1IF
Bit 0
Value on
POR, BOR
Value on all
other
RESETS
INT0IF
RBIF
0000 000x
0000 000u
TMR2IF
TMR1IF
-000 0000
-000 0000
Bit 1
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
IPR1
—
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
-000 0000
-000 0000
PIR2
—
—
—
—
BCLIF
LVDIF
TMR3IF
CCP2IF
-0-- 0000
-0-- 0000
PIE2
—
—
—
—
BCLIE
LVDIE
TMR3IE
CCP2IE
---- 0000
---- 0000
—
—
—
—
BCLIP
LVDIP
TMR3IP
CCP2IP
IPR2
---- 0000
---- 0000
ADRESH
A/D Result Register
xxxx xxxx
uuuu uuuu
ADRESL
A/D Result Register
xxxx xxxx
uuuu uuuu
ADCON0
—
—
CHS3
CHS3
CHS1
ADCON1
—
—
VCFG1
ADCON2
ADFM
—
—
—
—
PORTA
—
—
RA5
RA4
RA3
TRISA
—
VCFG0 PCFG3
CHS0
GO/DONE
ADON
0000 00-0
0000 00-0
PCFG2
PCFG1
PCFG0
---- -000
---- -000
ADCS2
ADCS1
ADCS0
0--- -000
0--- -000
RA2
RA1
RA0
--0x 0000
--0u 0000
--11 1111
--11 1111
PORTA Data Direction Register
PORTF
RF7
RF6
RF5
RF4
RF3
RF2
RF1
RF0
x000 0000
u000 0000
LATF
LATF7
LATF6
LATF5
LATF4
LATF3
LATF2
LATF1
LATF0
xxxx xxxx
uuuu uuuu
1111 1111
1111 1111
TRISF
PORTH(1)
LATH(1)
TRISH(1)
PORTF Data Direction Control Register
RH7
RH6
RH5
RH4
RH3
RH2
RH1
RH0
0000 xxxx
0000 xxxx
LATH7
LATH6
LATH5
LATH4
LATH3
LATH2
LATH1
LATH0
xxxx xxxx
uuuu uuuu
1111 1111
1111 1111
PORTH Data Direction Control Register
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used for A/D conversion.
Note 1: Only available on PIC18C801 devices.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 201
PIC18C601/801
NOTES:
DS39541A-page 202
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
18.0
LOW VOLTAGE DETECT
In many applications, the ability to determine if the
device voltage (VDD) is below a specified voltage level
is a desirable feature. A window of operation for the
application can be created, where the application software can do "housekeeping tasks", before the device
voltage exits the valid operating range. This can be
done using the Low Voltage Detect module.
This module is software programmable circuitry, where
a device voltage trip point can be specified (internal reference voltage or external voltage input). When the
voltage of the device becomes lower than the specified
point, an interrupt flag is set. If the interrupt is enabled,
the program execution will branch to the interrupt vector address and the software can then respond to that
interrupt source.
The Low Voltage Detect circuitry is completely under
software control. This allows the circuitry to be "turned
off" by the software, which minimizes the current consumption for the device.
Figure 18-2 shows the block diagram for the LVD module. A comparator uses an internally generated reference voltage as the set point. When the selected tap
output of the device voltage crosses the set point (is
lower than), the LVDIF bit (PIR registers) is set.
Each node in the resister divider represents a “trip
point” voltage. The “trip point” voltage is the minimum
supply voltage level at which the device can operate,
before the LVD module asserts an interrupt. When the
supply voltage is equal to the trip point, the voltage
tapped off of the resistor array (or external LVDIN input
pin) is equal to the voltage generated by the internal
voltage reference module. The comparator then generates an interrupt signal setting the LVDIF bit. This voltage is software programmable to any one of 16 values
(see Figure 18-2). The trip point is selected by
programming the LVDL3:LVDL0 bits (LVDCON<3:0>).
FIGURE 18-2:
VDD
Figure 18-1 shows a possible application voltage curve
(typically for batteries). Over time, the device voltage
decreases. When the device voltage equals voltage VA,
the LVD logic generates an interrupt. This occurs at time
TA. The application software then has the time, until the
device voltage is no longer in valid operating range, to
shut-down the system. Voltage point VB is the minimum
valid operating voltage specification. This occurs at time
TB. TB - TA is the total time for shut-down.
Voltage
LVD Control
Register
16 to 1 MUX
FIGURE 18-1:
LOW VOLTAGE DETECT
(LVD) BLOCK DIAGRAM
TYPICAL LOW VOLTAGE
DETECT APPLICATION
VA
VB
LVDIF
LVDIN
LVDEN
Internally Generated
Reference Voltage
Time
TA
TB
Legend:
VA = LVD trip point
VB = Minimum valid device operating range
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 203
PIC18C601/801
18.1
Control Register
The Low Voltage Detect Control register (Register 18-1)
controls the operation of the Low Voltage Detect
circuitry.
REGISTER 18-1:
LVDCON REGISTER
U-0
U-0
R-0
R/W-0
R/W-0
R/W-1
R/W-0
R/W-1
—
—
IRVST
LVDEN
LVDL3
LVDL2
LVDL1
LVDL0
bit 7
bit 0
bit 7-6
Unimplemented: Read as '0'
bit 5
IRVST: Internal Reference Voltage Stable Flag bit
1 = Indicates that the Low Voltage Detect logic will generate the interrupt flag at the specified
voltage range
0 = Indicates that the Low Voltage Detect logic will not generate the interrupt flag at the
specified voltage range and the LVD interrupt should not be enabled
bit 4
LVDEN: Low Voltage Detect Power Enable bit
1 = Enables LVD, powers up LVD circuit
0 = Disables LVD, powers down LVD circuit
bit 3-0
LVDL3:LVDL0: Low Voltage Detection Limit bits
1111 = External analog input is used (input comes from the LVDIN pin)
1110 = 4.5V
1101 = 4.2V
1100 = 4.0V - Reserved on PIC18C601/801
1011 = 3.8V - Reserved on PIC18C601/801
1010 = 3.6V - Reserved on PIC18C601/801
1001 = 3.5V - Reserved on PIC18C601/801
1000 = 3.3V - Reserved on PIC18C601/801
0111 = 3.0V - Reserved on PIC18C601/801
0110 = 2.8V - Reserved on PIC18C601/801
0101 = 2.7V - Reserved on PIC18C601/801
0100 = 2.5V - Reserved on PIC18C601/801
0011 = 2.4V - Reserved on PIC18C601/801
0010 = 2.2V - Reserved on PIC18C601/801
0001 = 2.0V - Reserved on PIC18C601/801
0000 = Reserved on PIC18C601/801 and PIC18LC801/601
LVDL3:LVDL0 modes which result in a trip point below the valid operating voltage of the device
are not tested.
Legend:
DS39541A-page 204
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
18.2
Operation
The following steps are needed to setup the LVD
module:
Depending on the power source for the device voltage,
the voltage normally decreases relatively slowly. This
means that the LVD module does not need to be constantly operating. To decrease current consumption,
the LVD circuitry only needs to be enabled for short
periods, where the voltage is checked. After doing the
check, the LVD module may be disabled.
1.
2.
3.
Each time that the LVD module is enabled, the circuitry
requires some time to stabilize. After the circuitry has
stabilized, all status flags may be cleared. The module
will then indicate the proper state of the system.
4.
5.
6.
Write the value to the LVDL3:LVDL0 bits
(LVDCON register), which selects the desired
LVD trip point.
Ensure that LVD interrupts are disabled (the
LVDIE bit is cleared or the GIE bit is cleared).
Enable the LVD module (set the LVDEN bit in
the LVDCON register).
Wait for the LVD module to stabilize (the IRVST
bit to become set).
Clear the LVD interrupt flag, which may have
falsely become set, until the LVD module has
stabilized (clear the LVDIF bit).
Enable the LVD interrupt (set the LVDIE and the
GIE bits).
Figure 18-3 shows typical waveforms that the LVD
module may be used to detect.
FIGURE 18-3:
LOW VOLTAGE DETECT WAVEFORMS
CASE 1:
LVDIF may not be set
VDD
VLVD
LVDIF
Enable LVD
Internally Generated
Reference Stable
50 ms
LVDIF cleared in software
CASE 2:
VDD
VLVD
LVDIF
Enable LVD
Internally Generated
Reference Stable
50 ms
LVDIF cleared in software
LVDIF cleared in software,
LVDIF remains set since LVD condition still exists
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 205
PIC18C601/801
18.2.1
REFERENCE VOLTAGE SET POINT
The Internal Reference Voltage of the LVD module may
be used by other internal circuitry (the programmable
Brown-out Reset). If these circuits are disabled (lower
current consumption), the reference voltage circuit
requires time to become stable before a low voltage condition can be reliably detected. This time is invariant of
system clock speed. This start-up time is specified in
electrical specification parameter #36. The low voltage
interrupt flag will not be enabled until a stable reference
voltage is reached. Refer to the waveform in Figure 18-3.
18.2.2
CURRENT CONSUMPTION
When the module is enabled, the LVD comparator and
voltage divider are enabled and will consume static current. The voltage divider can be tapped from multiple
places in the resistor array. Total current consumption,
when enabled, is specified in electrical specification
parameter #D022B.
DS39541A-page 206
18.3
External Analog Voltage Input
The LVD module has an additional feature that allows
the user to supply the trip point voltage to the module
from an external source (the LVDIN pin). The LVDIN pin
is used as the trip point when the LVDL3:LVDL0 bits
equal ’1111’. This state connects the LVDIN pin voltage to the comparator. The other comparator input is
connected to an internal reference voltage source.
18.4
Operation During SLEEP
When enabled, the LVD circuitry continues to operate
during SLEEP. If the device voltage crosses the trip
point, the LVDIF bit will be set and the device will wakeup from SLEEP. Device execution will continue from
the interrupt vector address, if interrupts have been
globally enabled.
18.5
Effects of a RESET
A device RESET forces all registers to their RESET
state. This forces the LVD module to be turned off.
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
19.0
SPECIAL FEATURES OF THE
CPU
while the power supply stabilizes. With these two timers on-chip, most applications need no external
RESET circuitry.
There are several features intended to maximize
system reliability, minimize cost through elimination of
external components and provide power saving
operating modes:
• OSC Selection
• RESET
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
• Interrupts
• Watchdog Timer (WDT)
• SLEEP
• ID Locations
19.1
PIC18C601/801 devices have a Watchdog Timer,
which can be permanently enabled/disabled via the
configuration bits, or it can be software controlled. By
default, the Watchdog Timer is disabled to allow software control. It runs off its own RC oscillator for cost
reduction. There are two timers that offer necessary
delays on power-up. One is the Oscillator Start-up
Timer (OST), intended to keep the chip in RESET until
the crystal oscillator is stable. The other is the Powerup Timer (PWRT), which provides a fixed delay on
power-up only, designed to keep the part in RESET
TABLE 19-1:
SLEEP mode is designed to offer a very low current
Power-down mode. The user can wake-up from
SLEEP through external RESET, Watchdog Timer
Wake-up or through an interrupt. Several oscillator
options are also available to allow the part to fit the
application. The RC oscillator option saves system
cost, while the LP crystal option saves power. By
default, HS oscillator mode is selected. There are two
main modes of operations for external memory interface: 8-bit and 16-bit (default). A set of configuration
bits are used to select various options.
Configuration Bits
The configuration bits can be programmed (read as ’0’),
or left unprogrammed (read as ’1’), to select various
device configurations. These bits are mapped starting
at program memory location 300000h.
The user will note that address 300000h is beyond the
user program memory space. In fact, it belongs to the
configuration memory space (300000h - 3FFFFFh),
which can only be accessed using table reads and
table writes.
CONFIGURATION BITS AND DEVICE IDs
File Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Default/
Unprogrammed
Value
300001h
CONFIG1H
—
—
—
—
—
—
FOSC1
FOSC0
---- --11
300002h
CONFIG2L
—
BW
—
—
—
—
—
PWRTEN
-1-- ---1
300003h
CONFIG2H
—
—
—
—
WDTEN
---- 1110
300006h
CONFIG4L
r
—
—
—
STVREN
1--- ---1
WDTPS2 WDTPS1 WDTPS0
—
—
—
3FFFFEh
DEVID1
DEV2
DEV1
DEV0
REV4
REV3
REV2
REV1
REV0
0000 0000
3FFFFFh
DEVID2
DEV10
DEV9
DEV8
DEV7
DEV6
DEV5
DEV4
DEV3
0000 0000
Legend: x = unknown, u = unchanged, - = unimplemented, q = value depends on condition, r = reserved, maintain ‘1’.
Shaded cells are unimplemented, read as ’0’.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 207
PIC18C601/801
REGISTER 19-1:
CONFIGURATION REGISTER 1 HIGH (CONFIG1H: BYTE ADDRESS 0300001h)
U-0
U-0
U-0
U-0
U-0
U-0
R/P-1
R/P-1
—
—
—
—
—
—
FOSC1
FOSC0
bit 7
bit 0
bit 7-2
Unimplemented: Read as ’0’
bit 2-0
FOSC1:FOSC0: Oscillator Selection bits
11 = RC oscillator
10 = HS oscillator
01 = EC oscillator
00 = LP oscillator
Legend:
r = Reserved
R = Readable bit
P = Programmable bit
- n = Value when device is unprogrammed
REGISTER 19-2:
U = Unimplemented bit, read as ‘0’
u = Unchanged from programmed state
CONFIGURATION REGISTER 2 LOW (CONFIG2L: BYTE ADDRESS 300002h)
U-0
R/P-1
U-0
U-0
U-0
U-0
U-0
R/P-1
—
BW
—
—
—
—
—
PWRTEN
bit 7
bit 0
bit 7
Unimplemented: Read as ’0’
bit 6
BW: External Bus Data Width bit
1 = 16-bit external bus mode
0 = 8-bit external bus mode
bit 5-1
Unimplemented: Read as ’0’
bit 0
PWRTEN: Power-up Timer Enable bit
1 = PWRT disabled
0 = PWRT enabled
Legend:
r = Reserved
R = Readable bit
P = Programmable bit
- n = Value when device is unprogrammed
DS39541A-page 208
Advance Information
U = Unimplemented bit, read as ‘0’
u = Unchanged from programmed state
 2001 Microchip Technology Inc.
PIC18C601/801
REGISTER 19-3:
CONFIGURATION REGISTER 2 HIGH (CONFIG2H: BYTE ADDRESS 300003H)
U-0
U-0
U-0
U-0
R/P-1
—
—
—
—
WDTPS2
R/P-1
R/P-1
WDTPS1 WDTPS0
R/P-1
WDTEN
bit 7
bit 0
bit 7-4
Unimplemented: Read as ’0’
bit 3-1
WDTPS2:WDTPS0: Watchdog Timer Postscale Select bits
000 =1:128
001 =1:64
010 =1:32
011 =1:16
100 =1:8
101 =1:4
110 =1:2
111 =1:1
bit 0
WDTEN: Watchdog Timer Enable bit
1 = WDT enabled
0 = WDT disabled (control is placed on the SWDTEN bit)
Legend:
r = Reserved
R = Readable bit
P = Programmable bit
- n = Value when device is unprogrammed
REGISTER 19-4:
U = Unimplemented bit, read as ‘0’
u = Unchanged from programmed state
CONFIGURATION REGISTER 4 LOW (CONFIG4L: BYTE ADDRESS 300006H)
R/P-1
U-0
U-0
U-0
U-0
U-0
R/P-1
R/P-1
r
—
—
—
—
—
—
STVREN
bit 7
bit 0
bit 7
Reserved: Maintain as ‘1’
bit 6-1
Unimplemented: Read as ’0’
bit 0
STVREN: Stack Full/Underflow RESET Enable bit
1 = Stack Full/Underflow will cause RESET
0 = Stack Full/Underflow will not cause RESET
Legend:
r = Reserved
R = Readable bit
P = Programmable bit
- n = Value when device is unprogrammed
 2001 Microchip Technology Inc.
U = Unimplemented bit, read as ‘0’
u = Unchanged from programmed state
Advance Information
DS39541A-page 209
PIC18C601/801
19.2
Watchdog Timer (WDT)
The Watchdog Timer is a free running on-chip RC oscillator, which does not require any external components.
This RC oscillator is separate from the RC oscillator of
the OSC1/CLKI pin. That means that the WDT will run,
even if the clock on the OSC1/CLKI and OSC2/CLKO
pins of the device has been stopped; for example, by
execution of a SLEEP instruction.
The WDT time-out period values may be found in the
Electrical Specifications section under parameter #31.
Values for the WDT postscaler may be assigned by
using configuration bits WDPS<3:1> in CONFIG2H
register. If the Watchdog Timer is disabled by configuration, values for the WDT postscaler may be assigned
using the SWDPS bits in the WDTCON register.
Note 1: The CLRWDT and SLEEP instructions
clear the WDT and the postscaler, if
assigned to the WDT, and prevent it from
timing out and generating a device
RESET condition.
During normal operation, a WDT time-out generates a
device RESET (Watchdog Timer Reset). If the device is
in SLEEP mode, a WDT time-out causes the device to
wake-up and continue with normal operation (Watchdog Timer Wake-up). The TO bit in the RCON register
will be cleared upon a WDT time-out.
By default, the Watchdog Timer is disabled by configuration to allow software control over Watchdog Timer
operation. If the WDT is enabled by configuration, software execution may not disable this function. When the
Watchdog Timer is disabled by configuration, the
SWDTEN bit in the WDTCON register enables/
disables the operation of the WDT.
REGISTER 19-5:
2: When a CLRWDT instruction is executed
and the prescaler is assigned to the WDT,
the prescaler count will be cleared, but
the prescaler assignment is not changed.
19.2.1
CONTROL REGISTER
Register 19-5 shows the WDTCON register. This is a
readable and writable register. It contains control bits to
control the Watchdog Timer from user software. If the
Watchdog Timer is enabled by configuration, this register setting is ignored.
WDTCON REGISTER
U-0
U-0
U-0
U-0
R/W-0
—
—
—
—
SWDPS2
R/W-0
R/W-0
R/W-0
SWDPS1 SWDPS0 SWDTEN
bit 7
bit 0
bit 7-4
Unimplemented: Read as ’0’
bit 3-1
SWDPS2:SWDPS0: Software Watchdog Timer Postscale Select bits
111 = 1:128
110 = 1:64
101 = 1:32
100 = 1:16
011 = 1:8
010 = 1:4
001 = 1:2
000 = 1:1
bit 0
SWDTEN: Software Controlled Watchdog Timer Enable bit
1 = Watchdog Timer is on
0 = Watchdog Timer is turned off if it is not disabled
Legend:
DS39541A-page 210
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
Advance Information
x = Bit is unknown
 2001 Microchip Technology Inc.
PIC18C601/801
19.2.2
WDT POSTSCALER
the device will use predefined set postscaler value. If
the device has the Watchdog Timer disabled by configuration bits, user software can set desired postscaler
value. When the device has the Watchdog Timer
enabled by configuration bits, by default, Watchdog
postscaler of 1:128 is selected.
The WDT has a postscaler that can extend the WDT
Reset period. The postscaler may be programmed by
the user software or is selected by configuration bits
WDTPS<2:0> in the CONFIG2H register. If the device
has the Watchdog Timer enabled by configuration bits,
FIGURE 19-1:
Watchdog Timer Block Diagram
WDT Timer
Postscaler
8
SWDTEN bit
8 - to - 1 MUX
WDTPS2:WDTPS0
WDT
Time-out
Note: WDPS2:WDPS0 are bits in a configuration register.
TABLE 19-2:
Name
CONFIG2H
RCON
WDTCON
SUMMARY OF WATCHDOG TIMER REGISTERS
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
—
—
—
—
WDTPS2
WDTPS1
WDTPS0
WDTEN
IPEN
r
—
RI
TO
PD
POR
r
—
—
—
—
SWDPS2
SWDPS1
SWDPS0
SWDTEN
Legend: Shaded cells are not used by the Watchdog Timer.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 211
PIC18C601/801
19.3
Power-down Mode (SLEEP)
Power-down mode is entered by executing a SLEEP
instruction.
Upon entering into Power-down mode, the following
actions are performed:
1.
2.
3.
4.
5.
Watchdog Timer is cleared and kept running.
PD bit in RCON register is cleared.
TO bit in RCON register is set.
Oscillator driver is turned off.
I/O ports maintain the status they had before the
SLEEP instruction was executed.
To achieve lowest current consumption, follow these
steps before switching to Power-down mode:
1.
2.
3.
4.
5.
Place all I/O pins at either VDD or VSS and
ensure no external circuitry is drawing current
from I/O pin.
Power-down A/D and external clocks.
Pull all hi-impedance inputs to high or low,
externally.
Place T0CKI at VSS or VDD.
Current consumption by PORTB on-chip pullups should be taken into account and disabled,
if necessary.
The MCLR pin must be at a logic high level (VIHMC).
19.3.1
WAKE-UP FROM SLEEP
The device can wake-up from SLEEP through one of
the following events:
1.
2.
3.
External RESET input on MCLR pin.
Watchdog Timer Wake-up (if WDT was
enabled).
Interrupt from INT pin, RB port change, or a
peripheral interrupt.
The following peripheral interrupts can wake the device
from SLEEP:
4.
TMR1 interrupt. Timer1 must be operating as
an asynchronous counter.
5. TMR3 interrupt. Timer3 must be operating as
an asynchronous counter.
6. CCP Capture mode interrupt.
7. Special event trigger (Timer1 in Asynchronous
mode using an external clock).
8. MSSP (START/STOP) bit detect interrupt.
9. MSSP transmit or receive in Slave mode
(SPI/I2C).
10. USART RX or TX (Synchronous Slave mode).
11. A/D conversion (when A/D clock source is RC).
External MCLR Reset will cause a device RESET. All
other events are considered a continuation of program
execution and will cause a "wake-up". The TO and PD
bits in the RCON register can be used to determine the
cause of the device RESET. The PD bit, which is set on
power-up, is cleared when SLEEP is invoked. The TO
bit is cleared, if a WDT time-out occurred (and caused
wake-up).
When the SLEEP instruction is being executed, the next
instruction (PC + 2) is pre-fetched. For the device to
wake-up through an interrupt event, the corresponding
interrupt enable bit must be set (enabled). Wake-up is
regardless of the state of the GIE bit. If the GIE bit is
clear (disabled), the device continues execution at the
instruction after the SLEEP instruction. If the GIE bit is
set (enabled), the device executes the instruction after
the SLEEP instruction and then branches to the interrupt address. In cases where the execution of the
instruction following SLEEP is not desirable, the user
should have a NOP after the SLEEP instruction.
19.3.2
WAKE-UP USING INTERRUPTS
When global interrupts are disabled (GIE cleared) and
any interrupt source has both its interrupt enable bit
and interrupt flag bit set, one of the following will occur:
• If an interrupt condition (interrupt flag bit and interrupt enable bits are set) occurs before the execution of a SLEEP instruction, the SLEEP instruction
will complete as a NOP. Therefore, the WDT and
WDT postscaler will not be cleared, the TO bit will
not be set and PD bits will not be cleared.
• If the interrupt condition occurs during or after
the execution of a SLEEP instruction, the device
will immediately wake-up from sleep. The SLEEP
instruction will be completely executed before the
wake-up. Therefore, the WDT and WDT
postscaler will be cleared, the TO bit will be set
and the PD bit will be cleared.
Even if the flag bits were checked before executing a
SLEEP instruction, it may be possible for flag bits to
become set before the SLEEP instruction completes. To
determine whether a SLEEP instruction executed, test
the PD bit. If the PD bit is set, the SLEEP instruction
was executed as a NOP.
To ensure that the WDT is cleared, a CLRWDT instruction should be executed before a SLEEP instruction.
Other peripherals cannot generate interrupts, since
during SLEEP, no on-chip clocks are present.
DS39541A-page 212
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
WAKE-UP FROM SLEEP THROUGH INTERRUPT(1,2)
FIGURE 19-2:
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
TOST(2)
CLKOUT(4)
INT pin
INTIF bit
Interrupt Latency(3)
GIEH bit
Processor in
SLEEP
INSTRUCTION FLOW
PC
PC
Instruction
Inst(PC) = SLEEP
Fetched
Instruction
Inst(PC - 1)
Executed
PC+2
PC+4
PC+4
Inst(PC + 2)
Inst(PC + 4)
SLEEP
Inst(PC + 2)
PC + 4
Dummy cycle
0008h
000Ah
Inst(0008h)
Inst(000Ah)
Dummy cycle
Inst(0008h)
Note 1: HS or LP oscillator mode assumed.
2: GIE set is assumed. In this case, after wake- up, the processor jumps to the interrupt routine.
If GIE is cleared, execution will continue in-line.
3: TOST = 1024TOSC (drawing not to scale). This delay will not occur for RC and EC osc modes.
4: CLKOUT is not available in these oscillator modes, but shown here for timing reference.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 213
PIC18C601/801
NOTES:
DS39541A-page 214
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
20.0
INSTRUCTION SET SUMMARY
The PIC18C601/801 instruction set adds many
enhancements to the previous PICmicro® instruction
sets, while maintaining an easy migration path from
them.
With few exceptions, instructions are a single program
memory word (16-bits). Each single word instruction is
divided into an OPCODE, which specifies the instruction type, and one or more operands which further
specify the operation of the instruction.
The instruction set is highly orthogonal and is grouped
into four basic categories:
•
•
•
•
Byte-oriented operations
Bit-oriented operations
Literal operations
Control operations
The PIC18C601/801 instruction set summary in
Table 20-2 lists byte-oriented, bit-oriented, literal
and control operations. Table 20-1 shows the opcode
field descriptions.
Most byte-oriented instructions have three operands:
1.
2.
3.
The file register (represented by ’f’)
The destination of the result
(represented by ’d’)
The accessed memory
(represented by ’a’)
The file register designator ‘f’ specifies which file register is to be used by the instruction.
The destination designator ‘d’ specifies where the
result of the operation is to be placed. If 'd' is zero, the
result is placed in the WREG register. If 'd' is one, the
result is placed in the file register specified in the
instruction.
All bit-oriented instructions have three operands:
1.
2.
3.
The file register (represented by ’f’)
The bit in the file register
(represented by ’b’)
The accessed memory
(represented by ’a’)
• A literal value to be loaded into a file register
(represented by ’k’)
• The desired FSR register to load the literal value
into (represented by ’f’)
• No operand required
(specified by ’—’)
The control instructions may use some of the following
operands:
• A program memory address (represented by ’n’)
• The mode of the Call or Return instructions
(represented by ’s’)
• The mode of the Table Read and Table Write
instructions (represented by ’m’)
• No operand required
(specified by ’—’)
All instructions are a single word, except for four double
word instructions. These four instructions were made
double word instructions so that all the required information is available in these 32 bits. In the second word,
the 4 MSbs are 1’s. If this second word is executed as
an instruction (by itself), it will execute as a NOP.
All single word instructions are executed in a single
instruction cycle, unless a conditional test is true, or the
program counter is changed as a result of the instruction. In these cases, the execution takes two instruction
cycles, with the additional instruction cycle(s) executed
as a NOP.The double word instructions execute in two
instruction cycles.
One instruction cycle consists of four oscillator periods.
Thus, for an oscillator frequency of 4 MHz, the normal
instruction execution time is 1 µs. If a conditional test is
true, or the program counter is changed as a result of
an instruction, the instruction execution time is 2 µs.
Two word branch instructions (if true) would take 3 µs.
Figure 20-1 shows the general formats that the instructions can have. All examples use the format ‘nnh’ to
represent a hexadecimal number, where ‘h’ signifies
a hexadecimal digit.
The bit field designator 'b' selects the number of the bit
affected by the operation, while the file register designator 'f' represents the number of the file in which the
bit is located.
 2001 Microchip Technology Inc.
The literal instructions may use some of the following
operands:
The Instruction Set Summary, shown in Table 20-2,
lists the instructions recognized by the Microchip
assembler (MPASMTM).
Section 20.1 provides a description of each instruction.
Advance Information
DS39541A-page 215
PIC18C601/801
TABLE 20-1:
OPCODE FIELD DESCRIPTIONS
Field
a
ACCESS
BANKED
bbb
BSR
d
dest
f
fs
fd
k
label
mm
*
*+
*+*
n
PRODH
PRODL
s
u
W
WREG
x
TBLPTR
TABLAT
TOS
PC
PCL
PCH
PCLATH
PCLATU
GIE
WDT
TO
PD
C, DC, Z, OV, N
[
]
(
)
→
< >
∈
italics
DS39541A-page 216
Description
RAM access bit
a = 0: RAM location in Access RAM (BSR register is ignored)
a = 1: RAM bank is specified by BSR register
ACCESS = 0: RAM access bit symbol
BANKED = 1: RAM access bit symbol
Bit address within an 8-bit file register (0 to 7)
Bank Select Register. Used to select the current RAM bank.
Destination select bit;
d = 0: store result in WREG,
d = 1: store result in file register f.
Destination either the WREG register or the specified register file location
8-bit Register file address (00h to FFh)
12-bit Register file address (000h to FFFh). This is the source address.
12-bit Register file address (000h to FFFh). This is the destination address.
Literal field, constant data or label (may be either an 8-bit, 12-bit or a 20-bit value)
Label name
The mode of the TBLPTR register for the Table Read and Table Write instructions
Only used with Table Read and Table Write instructions:
No change to register (such as TBLPTR with Table reads and writes)
Post-Increment register (such as TBLPTR with Table reads and writes)
Post-Decrement register (such as TBLPTR with Table reads and writes)
Pre-Increment register (such as TBLPTR with Table reads and writes)
The relative address (2’s complement number) for relative branch instructions, or the direct
address for Call/Branch and Return instructions
Product of Multiply high byte (Register at address FF4h)
Product of Multiply low byte (Register at address FF3h)
Fast Call / Return mode select bit.
s = 0: do not update into/from shadow registers
s = 1: certain registers loaded into/from shadow registers (Fast mode)
Unused or Unchanged (Register at address FE8h)
W = 0: Destination select bit symbol
Working register (accumulator) (Register at address FE8h)
Don't care (0 or 1)
The assembler will generate code with x = 0. It is the recommended form of use for compatibility
with all Microchip software tools.
21-bit Table Pointer (points to a Program Memory location) (Register at address FF6h)
8-bit Table Latch (Register at address FF5h)
Top-of-Stack
Program Counter
Program Counter Low Byte (Register at address FF9h)
Program Counter High Byte
Program Counter High Byte Latch (Register at address FFAh)
Program Counter Upper Byte Latch (Register at address FFBh)
Global Interrupt Enable bit
Watchdog Timer
Time-out bit
Power-down bit
ALU status bits Carry, Digit Carry, Zero, Overflow, Negative
Optional
Contents
Assigned to
Register bit field
In the set of
User defined term (font is courier)
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 20-1:
GENERAL FORMAT FOR INSTRUCTIONS
Byte-oriented file register operations
15
10
OPCODE
9
d
8 7
a
Example Instruction
0
f (FILE #)
ADDWF MYREG, W
d = 0 for result destination to be WREG register
d = 1 for result destination to be file register (f)
a = 0 to force Access Bank
a = 1 for BSR to select Bank
f = 8-bit file register address
Byte to Byte move operations (2-word)
15
12 11
OPCODE
15
0
f (Source FILE #)
12 11
MOVFF MYREG1, MYREG2
0
f (Destination FILE #)
1111
f = 12-bit file register address
Bit-oriented file register operations
15
12 11
9 8 7
OPCODE b (BIT #) a
0
f (FILE #)
BSF MYREG, bit
b = 3-bit position of bit in file register (f)
a = 0 to force Access Bank
a = 1 for BSR to select Bank
f = 8-bit file register address
Literal operations
15
8
7
0
OPCODE
k (literal)
MOVLW 7Fh
k = 8-bit immediate value
Control operations
CALL, GOTO and Branch operations
15
8 7
OPCODE
15
0
GOTO Label
n<7:0> (literal)
12 11
0
n<19:8> (literal)
1111
n = 20-bit immediate value
15
8 7
OPCODE
15
0
CALL MYFUNC
n<7:0> (literal)
S
12 11
0
1111
n<19:8> (literal)
S = Fast bit
15
11 10
OPCODE
0
15
8 7
OPCODE
0
6
OPCODE
 2001 Microchip Technology Inc.
4
f
11
1111
BC MYFUNC
n<7:0> (literal)
15
15
BRA MYFUNC
n<10:0> (literal)
7
0000
0
k<11:8>(lit.)
LFSR FSR0, 100h
0
k<7:0> (literal)
Advance Information
DS39541A-page 217
PIC18C601/801
TABLE 20-2:
PIC18C601/801 INSTRUCTION SET
Mnemonic,
Operands
16-Bit Instruction Word
Description
Cycles
MSb
BYTE-ORIENTED FILE REGISTER OPERATIONS
f [,d [,a]] Add WREG and f
ADDWF
ADDWFC f [,d [,a]] Add WREG and Carry bit to f
f [,d [,a]] AND WREG with f
ANDWF
CLRF
f [,a]
Clear f
f [,d [,a]] Complement f
COMF
CPFSEQ f [,a]
Compare f with WREG, skip =
CPFSGT f [,a]
Compare f with WREG, skip >
CPFSLT f [,a]
Compare f with WREG, skip <
f [,d [,a]] Decrement f
DECF
DECFSZ f [,d [,a]] Decrement f, Skip if 0
DCFSNZ f [,d [,a]] Decrement f, Skip if Not 0
INCF
f [,d [,a]] Increment f
f [,d [,a]] Increment f, Skip if 0
INCFSZ
f [,d [,a]] Increment f, Skip if Not 0
INFSNZ
f [,d [,a]] Inclusive OR WREG with f
IORWF
f [,d [,a]] Move f
MOVF
fs, fd
MOVFF
Move fs (source) to 1st word
fd (destination)2nd word
MOVWF f [,a]
Move WREG to f
MULWF
Multiply WREG with f
f [,a]
NEGF
Negate f
f [,a]
RLCF
f [,d [,a]] Rotate Left f through Carry
RLNCF
f [,d [,a]] Rotate Left f (No Carry)
RRCF
f [,d [,a]] Rotate Right f through Carry
RRNCF
f [,d [,a]] Rotate Right f (No Carry)
SETF
Set f
f [,a]
SUBFWB f [,d [,a]] Subtract f from WREG with
borrow
SUBWF
f [,d [,a]] Subtract WREG from f
SUBWFB f [,d [,a]] Subtract WREG from f with
borrow
SWAPF
f [,d [,a]] Swap nibbles in f
TSTFSZ f [,a]
Test f, skip if 0
XORWF
f [,d [,a]] Exclusive OR WREG with f
1
1
1
1
1
1 (2 or 3)
1 (2 or 3)
1 (2 or 3)
1
1 (2 or 3)
1 (2 or 3)
1
1 (2 or 3)
1 (2 or 3)
1
1
2
LSb
Status
Affected
Notes
C, DC, Z, OV, N
C, DC, Z, OV, N
Z, N
Z
Z, N
None
None
None
C, DC, Z, OV, N
None
None
C, DC, Z, OV, N
None
None
Z, N
Z, N
None
1, 2, 6
1, 2, 6
1,2, 6
2, 6
1, 2, 6
4, 6
4, 6
1, 2, 6
1, 2, 3, 4, 6
1, 2, 3, 4, 6
1, 2, 6
1, 2, 3, 4, 6
4, 6
1, 2, 6
1, 2, 6
1, 6
None
None
C, DC, Z, OV, N
C, Z, N
Z, N
C, Z, N
Z, N
None
C, DC, Z, OV, N
6
6
1, 2, 6
6
1, 2, 6
6
6
6
1, 2, 6
1
1
1
1
1
1
1
1
1
0010
0010
0001
0110
0001
0110
0110
0110
0000
0010
0100
0010
0011
0100
0001
0101
1100
1111
0110
0000
0110
0011
0100
0011
0100
0110
0101
01da
01da
01da
101a
11da
001a
010a
000a
01da
11da
11da
10da
11da
10da
00da
00da
ffff
ffff
111a
001a
110a
01da
01da
00da
00da
100a
01da
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
1
1
0101
0101
11da
10da
ffff
ffff
ffff C, DC, Z, OV, N 6
ffff C, DC, Z, OV, N 1, 2, 6
0011
1
1 (2 or 3) 0110
0001
1
10da
011a
10da
ffff
ffff
ffff
ffff None
ffff None
ffff Z, N
4, 6
1, 2, 6
6
BIT-ORIENTED FILE REGISTER OPERATIONS
BCF
f, b [,a] Bit Clear f
1
1001 bbba ffff ffff None
1, 2, 6
BSF
f, b [,a] Bit Set f
1
1000 bbba ffff ffff None
1, 2, 6
BTFSC
f, b [,a] Bit Test f, Skip if Clear
1 (2 or 3) 1011 bbba ffff ffff None
3, 4, 6
BTFSS
f, b [,a] Bit Test f, Skip if Set
1 (2 or 3) 1010 bbba ffff ffff None
3, 4, 6
BTG
f [,d [,a]] Bit Toggle f
1
0111 bbba ffff ffff None
1, 2, 6
Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value
present on the pins themselves. For example, if the data latch is ’1’ for a pin configured as input and is driven low by an
external device, the data will be written back with a ’0’.
2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if
assigned.
3: If Program Counter (PC) is modified, or a conditional test is true, the instruction requires two cycles. The second cycle
is executed as a NOP.
4: Some instructions are 2-word instructions. The second word of these instructions will be executed as a NOP, unless the
first word of the instruction retrieves the information embedded in these 16-bits. This ensures that all program memory
locations have a valid instruction.
5: If the table write starts the write cycle to internal memory, the write will continue until terminated.
6: Microchip’s MPASMTM Assembler automatically defaults destination bit ’d’ to ’1’, while access bit ’a’ defaults to ’1’ or ’0’,
according to address of register being used.
DS39541A-page 218
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TABLE 20-2:
PIC18C601/801 INSTRUCTION SET (CONTINUED)
Mnemonic,
Operands
16-Bit Instruction Word
Description
Cycles
MSb
CONTROL OPERATIONS
BC
n
Branch if Carry
BN
n
Branch if Negative
BNC
n
Branch if Not Carry
BNN
n
Branch if Not Negative
BNOV
n
Branch if Not Overflow
BNZ
n
Branch if Not Zero
BOV
n
Branch if Overflow
BRA
n
Branch Unconditionally
BZ
n
Branch if Zero
CALL
n, s
Call subroutine1st word
2nd word
CLRWDT —
Clear Watchdog Timer
DAW
—
Decimal Adjust WREG
GOTO
n
Go to address1st word
2nd word
NOP
—
No Operation
NOP
—
No Operation (Note 4)
POP
—
Pop top of return stack (TOS)
PUSH
—
Push top of return stack (TOS)
RCALL
n
Relative Call
RESET
Software device RESET
RETFIE
s
Return from interrupt enable
RETLW
RETURN
SLEEP
Note 1:
2:
3:
4:
5:
6:
1 (2)
1 (2)
1 (2)
1 (2)
1 (2)
2
1 (2)
1 (2)
1 (2)
2
1
1
2
1110
1110
1110
1110
1110
1110
1110
1101
1110
1110
1111
0000
0000
1110
1111
0000
1111
0000
0000
1101
0000
0000
LSb
0010
0110
0011
0111
0101
0001
0100
0nnn
0000
110s
kkkk
0000
0000
1111
kkkk
0000
xxxx
0000
0000
1nnn
0000
0000
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
kkkk
kkkk
0000
0000
kkkk
kkkk
0000
xxxx
0000
0000
nnnn
1111
0001
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
kkkk
kkkk
0100
0111
kkkk
kkkk
0000
xxxx
0110
0101
nnnn
1111
000s
Status
Affected
Notes
None
None
None
None
None
None
None
None
None
None
TO, PD
C
None
None
None
None
None
None
All
GIE/GIEH,
PEIE/GIEL
k
Return with literal in WREG
2
0000 1100 kkkk kkkk None
Return from Subroutine
s
0000 0000 0001 001s None
2
—
Go into Standby mode
1
0000 0000 0000 0011 TO, PD
When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value
present on the pins themselves. For example, if the data latch is '1' for a pin configured as input and is driven low by an
external device, the data will be written back with a '0'.
If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if
assigned.
If Program Counter (PC) is modified, or a conditional test is true, the instruction requires two cycles. The second cycle
is executed as a NOP.
Some instructions are 2-word instructions. The second word of these instructions will be executed as a NOP, unless the
first word of the instruction retrieves the information embedded in these 16-bits. This ensures that all program memory
locations have a valid instruction.
If the table write starts the write cycle to internal memory, the write will continue until terminated.
Microchip’s MPASMTM Assembler automatically defaults destination bit ’d’ to ’1’, while access bit ’a’ defaults to ’1’ or ’0’,
according to address of register being used.
 2001 Microchip Technology Inc.
1
1
1
1
2
1
2
Advance Information
DS39541A-page 219
PIC18C601/801
TABLE 20-2:
PIC18C601/801 INSTRUCTION SET (CONTINUED)
Mnemonic,
Operands
16-Bit Instruction Word
Description
Cycles
MSb
LSb
Status
Affected
Notes
LITERAL OPERATIONS
ADDLW
k
Add literal and WREG
1
0000 1111 kkkk kkkk C, DC, Z, OV, N
ANDLW
k
AND literal with WREG
1
0000 1011 kkkk kkkk Z, N
IORLW
k
Inclusive OR literal with WREG 1
0000 1001 kkkk kkkk Z, N
LFSR
f, k
Load FSR (f) with a 12-bit
2
1110 1110 00ff kkkk None
literal (k)
1111 0000 kkkk kkkk
MOVLB
k
Move literal to BSR<3:0>
1
0000 0001 0000 kkkk None
MOVLW
k
Move literal to WREG
1
0000 1110 kkkk kkkk None
MULLW
k
Multiply literal with WREG
1
0000 1101 kkkk kkkk None
RETLW
k
Return with literal in WREG
2
0000 1100 kkkk kkkk None
SUBLW
k
Subtract WREG from literal
1
0000 1000 kkkk kkkk C, DC, Z, OV, N
XORLW
k
Exclusive OR literal with WREG 1
0000 1010 kkkk kkkk Z, N
DATA MEMORY ↔ PROGRAM MEMORY OPERATIONS
TBLRD*
Table Read
2
0000 0000 0000 1000 None
TBLRD*+
Table Read with post-increment
0000 0000 0000 1001 None
TBLRD*Table Read with post-decrement
0000 0000 0000 1010 None
TBLRD+*
Table Read with pre-increment
0000 0000 0000 1011 None
TBLWT*
Table Write
2 (5)
0000 0000 0000 1100 None
TBLWT*+
Table Write with post-increment
0000 0000 0000 1101 None
TBLWT*Table Write with post-decrement
0000 0000 0000 1110 None
TBLWT+*
Table Write with pre-increment
0000 0000 0000 1111 None
Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value
present on the pins themselves. For example, if the data latch is ’1’ for a pin configured as input and is driven low by an
external device, the data will be written back with a ’0’.
2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if
assigned.
3: If Program Counter (PC) is modified, or a conditional test is true, the instruction requires two cycles. The second cycle
is executed as a NOP.
4: Some instructions are 2-word instructions. The second word of these instructions will be executed as a NOP, unless the
first word of the instruction retrieves the information embedded in these 16-bits. This ensures that all program memory
locations have a valid instruction.
5: If the table write starts the write cycle to internal memory, the write will continue until terminated.
6: Microchip’s MPASMTM Assembler automatically defaults destination bit ’d’ to ’1’, while access bit ’a’ defaults to ’1’ or ’0’,
according to address of register being used.
DS39541A-page 220
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
20.1
Instruction Set
ADDLW
ADD literal to WREG
ADDWF
ADD WREG to f
Syntax:
[ label ] ADDLW
Syntax:
[ label ] ADDWF
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
(WREG) + k → WREG
Status Affected:
N,OV, C, DC, Z
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(WREG) + (f) → dest
Status Affected:
N,OV, C, DC, Z
Encoding:
0000
Description:
1111
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Example:
kkkk
Q2
Q3
Q4
Read
literal ’k’
Process
Data
Write to
WREG
ADDLW
15h
Before Instruction
=
=
=
=
=
=
10h
?
?
?
?
?
=
=
=
=
=
=
Encoding:
0010
01da
f [,d [,a]]
ffff
ffff
Description:
Add WREG to register ’f’. If ’d’ is 0,
the result is stored in WREG. If ’d’ is
1, the result is stored back in register
'f' (default). If ’a’ is 0, the Access
Bank will be selected. If ’a’ is 1, the
Bank will be selected as per the BSR
value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Example:
ADDWF
REG, W
Before Instruction
After Instruction
WREG
N
OV
C
DC
Z
kkkk
The contents of WREG are added to
the 8-bit literal ’k’ and the result is
placed in WREG.
Words:
WREG
N
OV
C
DC
Z
k
25h
0
0
0
0
0
WREG
REG
N
OV
C
DC
Z
=
=
=
=
=
=
=
17h
0C2h
?
?
?
?
?
After Instruction
WREG
REG
N
OV
C
DC
Z
 2001 Microchip Technology Inc.
Advance Information
=
=
=
=
=
=
=
0D9h
0C2h
1
0
0
0
0
DS39541A-page 221
PIC18C601/801
ADDWFC
ADD WREG and Carry bit to f
ANDLW
AND literal with WREG
Syntax:
[ label ] ADDWFC
Syntax:
[ label ] ANDLW
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
f [,d [,a]]
Operation:
(WREG) + (f) + (C) → dest
Status Affected:
N,OV, C, DC, Z
Encoding:
0010
Description:
1
Cycles:
1
0 ≤ k ≤ 255
Operation:
(WREG) .AND. k → WREG
Status Affected:
N,Z
ffff
0000
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
ADDWFC
REG, W
Example:
Before Instruction
=
=
=
=
=
=
=
1
02h
4Dh
?
?
?
?
1011
kkkk
kkkk
Description:
The contents of WREG are AND’ed
with the 8-bit literal 'k'. The result is
placed in WREG.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read literal
’k’
Process
Data
Write to
WREG
Example:
Q Cycle Activity:
Q1
C
REG
WREG
N
OV
DC
Z
ffff
Operands:
Encoding:
Add WREG, the Carry Flag and data
memory location ’f’. If ’d’ is 0, the
result is placed in WREG. If ’d’ is 1,
the result is placed in data memory
location 'f'. If ’a’ is 0, the Access Bank
will be selected. If ’a’ is 1, the Bank
will be selected as per the BSR value.
Words:
Decode
00da
k
ANDLW
5Fh
Before Instruction
WREG
N
Z
=
=
=
0A3h
?
?
After Instruction
WREG
N
Z
=
=
=
03h
0
0
After Instruction
C
REG
WREG
N
OV
DC
Z
=
=
=
=
=
=
=
DS39541A-page 222
0
02h
50h
0
0
0
0
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
ANDWF
AND WREG with f
Syntax:
[ label ] ANDWF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
f [,d [,a]]
Operation:
(WREG) .AND. (f) → dest
Status Affected:
N,Z
Encoding:
0001
ffff
ffff
[ label ] BC
Operands:
-128 ≤ n ≤ 127
Operation:
if carry bit is ’1’
(PC) + 2 + 2n → PC
Status Affected:
None
1110
n
0010
nnnn
nnnn
If the Carry bit is ’1’, then the program will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
1
Words:
1
1
Cycles:
1(2)
Words:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
ANDWF
REG, W
Before Instruction
WREG
REG
N
Z
Syntax:
Description:
The contents of WREG are AND’ed
with register 'f'. If 'd' is 0, the result is
stored in WREG. If 'd' is 1, the result
is stored back in register 'f' (default).
If ’a’ is 0, the Access Bank will be
selected. If ’a’ is 1, the bank will be
selected as per the BSR value.
Example:
Branch if Carry
Encoding:
01da
Description:
Decode
BC
=
=
=
=
17h
0C2h
?
?
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1
Decode
Q2
Q3
Read literal
’n’
Q4
Process
Data
No
operation
After Instruction
WREG
REG
N
Z
=
=
=
=
02h
0C2h
0
0
Example:
HERE
BC
5
Before Instruction
PC
=
address (HERE)
=
=
=
=
1;
address (HERE+12)
0;
address (HERE+2)
After Instruction
If Carry
PC
If Carry
PC
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 223
PIC18C601/801
BCF
Bit Clear f
Syntax:
[ label ] BCF
Operands:
0 ≤ f ≤ 255
0≤b≤7
a ∈ [0,1]
Operation:
0 → f<b>
Status Affected:
None
Encoding:
1001
f, b [,a]
ffff
ffff
Bit 'b' in register 'f' is cleared. If ’a’ is
0, the Access Bank will be selected,
overriding the BSR value. If ’a’ = 1,
the Bank will be selected as per the
BSR value.
Words:
1
Cycles:
1
Decode
Q2
Read
register ’f’
Example:
BCF
Before Instruction
FLAG_REG = 0C7h
After Instruction
FLAG_REG = 47h
Branch if Negative
Syntax:
[ label ] BN
Operands:
-128 ≤ n ≤ 127
Operation:
if negative bit is ’1’
(PC) + 2 + 2n → PC
Status Affected:
None
Encoding:
bbba
Description:
Q Cycle Activity:
Q1
BN
Q3
Q4
Process
Data
FLAG_REG,
Write
register ’f’
7
1110
n
0110
nnnn
nnnn
Description:
If the Negative bit is ’1’, then the program will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
Words:
1
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1
Decode
Q2
Q3
Q4
Read literal
’n’
Process
Data
No
operation
Example:
HERE
BN
Jump
Before Instruction
PC
=
address (HERE)
=
=
=
=
1;
address (Jump)
0;
address (HERE+2)
After Instruction
If Negative
PC
If Negative
PC
DS39541A-page 224
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
BNC
Branch if Not Carry
BNN
Branch if Not Negative
Syntax:
[ label ] BNC
Syntax:
[ label ] BNN
Operands:
-128 ≤ n ≤ 127
Operands:
-128 ≤ n ≤ 127
Operation:
if carry bit is ’0’
(PC) + 2 + 2n → PC
Operation:
if negative bit is ’0’
(PC) + 2 + 2n → PC
Status Affected:
None
Status Affected:
None
Encoding:
1110
n
0011
nnnn
nnnn
Encoding:
1110
n
0111
nnnn
nnnn
Description:
If the Carry bit is ’0’, then the
program will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
Description:
If the Negative bit is ’0’, then the
program will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
Words:
1
Words:
1
Cycles:
1(2)
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q1
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Q2
Q3
Q4
Decode
Read literal
’n’
Process
Data
Write to PC
Decode
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Q2
Q3
Q4
Read literal
’n’
Process
Data
No
operation
If No Jump:
Q1
Decode
Example:
HERE
BNC
Q2
Q3
Q4
Read literal
’n’
Process
Data
No
operation
HERE
BNN
Jump
Before Instruction
=
address (HERE)
PC
=
=
=
=
0;
address (Jump)
1;
address (HERE+2)
After Instruction
If Carry
PC
If Carry
PC
Decode
Example:
Jump
Before Instruction
PC
If No Jump:
Q1
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE+2)
After Instruction
 2001 Microchip Technology Inc.
If Negative
PC
If Negative
PC
Advance Information
DS39541A-page 225
PIC18C601/801
BNOV
Branch if Not Overflow
BNZ
Branch if Not Zero
Syntax:
[ label ] BNOV
Syntax:
[ label ] BNZ
Operands:
-128 ≤ n ≤ 127
Operands:
-128 ≤ n ≤ 127
Operation:
if overflow bit is ’0’
(PC) + 2 + 2n → PC
Operation:
if zero bit is ’0’
(PC) + 2 + 2n → PC
Status Affected:
None
Status Affected:
None
Encoding:
1110
n
0101
nnnn
nnnn
Encoding:
1110
n
0001
nnnn
nnnn
Description:
If the Overflow bit is ’0’, then the
program will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
Description:
If the Zero bit is ’0’, then the program
will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
Words:
1
Words:
1
Cycles:
1(2)
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q1
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Q2
Q3
Q4
Decode
Read literal
’n’
Process
Data
Write to PC
Decode
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Q2
Q3
Q4
Read literal
’n’
Process
Data
No
operation
If No Jump:
Q1
Decode
Example:
HERE
DS39541A-page 226
Q2
Q3
Q4
Read literal
’n’
Process
Data
No
operation
HERE
BNZ
Jump
Before Instruction
=
address (HERE)
PC
=
=
=
=
0;
address (Jump)
1;
address (HERE+2)
After Instruction
If Overflow
PC
If Overflow
PC
Decode
Example:
BNOV Jump
Before Instruction
PC
If No Jump:
Q1
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE+2)
After Instruction
If Zero
PC
If Zero
PC
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
BRA
Unconditional Branch
BSF
Bit Set f
Syntax:
[ label ] BRA
Syntax:
[ label ] BSF
Operands:
-1024 ≤ n ≤ 1023
Operands:
Operation:
(PC) + 2 + 2n → PC
Status Affected:
None
0 ≤ f ≤ 255
0≤b≤7
a ∈ [0,1]
Operation:
1 → f<b>
Status Affected:
None
Encoding:
Description:
1101
1
Cycles:
2
Q Cycle Activity:
Q1
No
operation
0nnn
nnnn
nnnn
Add the 2’s complement number ’2n’
to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is a twocycle instruction.
Words:
Decode
n
Q2
Q3
Q4
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
Encoding:
HERE
BRA
Jump
PC
=
address (HERE)
PC
=
ffff
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write
register ’f’
BSF
FLAG_REG, 7
Before Instruction
=
0Ah
=
8Ah
After Instruction
FLAG_REG
After Instruction
ffff
Bit 'b' in register 'f' is set. If ’a’ is 0
Access Bank will be selected, overriding the BSR value. If ’a’ is 1, the
Bank will be selected as per the BSR
value (default).
FLAG_REG
Before Instruction
bbba
Description:
Example:
Example:
1000
f, b [,a]
address (Jump)
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 227
PIC18C601/801
BTFSC
Bit Test File, Skip if Clear
BTFSS
Bit Test File, Skip if Set
Syntax:
[ label ] BTFSC f, b [,a]
Syntax:
[ label ] BTFSS f, b [,a]
Operands:
0 ≤ f ≤ 255
0≤b≤7
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
0≤b<7
a ∈ [0,1]
Operation:
skip if (f<b>) = 0
Operation:
skip if (f<b>) = 1
Status Affected:
None
Status Affected:
None
Encoding:
1011
bbba
ffff
ffff
Description:
If bit 'b' in register ’f' is 0, then the next
instruction is skipped.
If bit 'b' is 0, then the next instruction
fetched during the current instruction
execution is discarded, and a NOP is
executed instead, making this a twocycle instruction. If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will be
selected as per the BSR value.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
No
operation
Encoding:
1010
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
FALSE
TRUE
BTFSC
:
:
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Decode
DS39541A-page 228
Q2
Q3
Q4
Read
register ’f’
Process
Data
No
operation
If skip:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
FLAG, 1
Example:
HERE
FALSE
TRUE
=
address (HERE)
Before Instruction
=
=
=
=
0;
address (TRUE)
1;
address (FALSE)
After Instruction
PC
After Instruction
If FLAG<1>
PC
If FLAG<1>
PC
ffff
If bit 'b' in register 'f' is 1 then the next
instruction is skipped.
If bit 'b' is 1, then the next instruction
fetched during the current instruction
execution, is discarded and a NOP is
executed instead, making this a twocycle instruction. If ’a’ is 0, the
Access Bank will be selected, overriding the BSR value. If ’a’ is 1, the
Bank will be selected as per the BSR
value.
Before Instruction
PC
ffff
Description:
If skip:
No
operation
bbba
If FLAG<1>
PC
If FLAG<1>
PC
Advance Information
BTFSS
:
:
FLAG, 1
=
address (HERE)
=
=
=
=
0;
address (FALSE)
1;
address (TRUE)
 2001 Microchip Technology Inc.
PIC18C601/801
BTG
Bit Toggle f
BOV
Branch if Overflow
Syntax:
[ label ] BTG f, b [,a]
Syntax:
[ label ] BOV
Operands:
0 ≤ f ≤ 255
0≤b<7
a ∈ [0,1]
Operands:
-128 ≤ n ≤ 127
Operation:
if overflow bit is ’1’
(PC) + 2 + 2n → PC
Status Affected:
None
Operation:
(f<b>) → f<b>
Status Affected:
None
Encoding:
Encoding:
0111
bbba
ffff
ffff
Description:
Bit ’b’ in data memory location ’f’ is
inverted. If ’a’ is 0, the Access Bank
will be selected, overriding the BSR
value. If ’a’ is 1, the Bank will be
selected as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Read
register ’f’
Example:
BTG
Q4
Process
Data
PORTC,
4
Before Instruction:
PORTC
=
0111 0101 [75h]
After Instruction:
PORTC
=
0110 0101 [65h]
Write
register ’f’
1110
n
0100
nnnn
nnnn
Description:
If the Overflow bit is ’1’, then the program will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
Words:
1
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1
Decode
Q2
Q3
Q4
Read literal
’n’
Process
Data
No
operation
Example:
HERE
BOV
Jump
Before Instruction
PC
=
address (HERE)
=
=
=
=
1;
address (Jump)
0;
address (HERE+2)
After Instruction
If Overflow
PC
If Overflow
PC
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 229
PIC18C601/801
BZ
Branch if Zero
CALL
Subroutine Call
Syntax:
[ label ] BZ
Syntax:
[ label ] CALL k [,s]
Operands:
-128 ≤ n ≤ 127
Operands:
Operation:
if Zero bit is ’1’
(PC) + 2 + 2n → PC
0 ≤ k ≤ 1048575
s ∈ [0,1]
Operation:
(PC) + 4 → TOS,
k → PC<20:1>,
if s = 1
(WREG) → WS,
(STATUS) → STATUSS,
(BSR) → BSRS
Status Affected:
None
Status Affected:
n
None
Encoding:
1110
Description:
0000
nnnn
nnnn
If the Zero bit is ’1’, then the program
will branch.
The 2’s complement number ’2n’ is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC+2+2n. This instruction is then a
two-cycle instruction.
Words:
1
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1
Decode
Q2
Q3
Q4
Read literal
’n’
Process
Data
No
operation
Example:
HERE
BZ
Encoding:
1st word (k<7:0>)
2nd word(k<19:8>)
1110
1111
110s
k19kkk
k7kkk
kkkk
Description:
Subroutine call of entire 2M byte
memory range. First, return address
(PC+ 4) is pushed onto the return
stack. If ’s’ = 1, the WREG, STATUS
and BSR registers are also pushed
into their respective shadow registers, WS, STATUSS and BSRS.
If 's' = 0, no update occurs
(default). Then the 20-bit value ’k’ is
loaded into PC<20:1>. CALL is a
two-cycle instruction.
Words:
2
Cycles:
2
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read literal
’k’<7:0>,
Push PC to
stack
Read literal
’k’<19:8>,
Write to PC
No
operation
No
operation
No
operation
No
operation
Jump
Before Instruction
PC
=
address (HERE)
=
=
=
=
1;
address (Jump)
0;
address (HERE+2)
After Instruction
If Zero
PC
If Zero
PC
kkkk0
kkkk8
Example:
HERE
CALL
THERE, FAST
Before Instruction
PC
=
Address (HERE)
After Instruction
PC
=
TOS
=
WS
=
BSRS
=
STATUSS =
DS39541A-page 230
Advance Information
Address (THERE)
Address (HERE + 4)
WREGREG
BSR
STATUS
 2001 Microchip Technology Inc.
PIC18C601/801
CLRF
Clear f
Syntax:
[label] CLRF
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
000h → f
1→Z
Status Affected:
Z
Encoding:
0110
f [,a]
101a
ffff
ffff
CLRWDT
Clear Watchdog Timer
Syntax:
[ label ] CLRWDT
Operands:
None
Operation:
000h → WDT,
000h → WDT postscaler,
1 → TO,
1 → PD
Status Affected:
TO, PD
Clears the contents of the specified
register. If ’a’ is 0, the Access Bank
will be selected, overriding the BSR
value. If ’a’ is 1, the Bank will be
selected as per the BSR value.
Encoding:
Description:
CLRWDT instruction resets the
Watchdog Timer. It also resets the
postscaler of the WDT. Status bits
TO and PD are set.
Words:
1
Words:
1
Cycles:
1
Cycles:
1
Description:
Q Cycle Activity:
Q1
Decode
Example:
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write
register ’f’
CLRF
FLAG_REG
Before Instruction
FLAG_REG
Z
Q Cycle Activity:
Q1
Decode
Example:
0000
0000
0100
Q2
Q3
Q4
No
operation
Process
Data
No
operation
CLRWDT
Before Instruction
=
=
5Ah
?
After Instruction
FLAG_REG
Z
0000
=
=
00h
0
WDT counter
WDT postscaler
TO
PD
?
?
?
?
=
=
=
=
00h
0
1
1
After Instruction
WDT counter
WDT postscaler
TO
PD
 2001 Microchip Technology Inc.
=
=
=
=
Advance Information
DS39541A-page 231
PIC18C601/801
COMF
Syntax:
[ label ] COMF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
( f ) → dest
Status Affected:
N,Z
Encoding:
0001
Description:
f [,d [,a]]
ffff
ffff
The contents of register ’f’ are complemented. If ’d’ is 0 the result is
stored in WREG. If ’d’ is 1 the result
is stored back in register ’f’
(default). If ’a’ is 0, the Access
Bank will be selected, overriding
the BSR value. If ’a’ is 1, the Bank
will be selected as per the BSR
value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
11da
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Example:
COMF
REG
Syntax:
[ label ] CPFSEQ
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(f) – (WREG),
skip if (f) = (WREG)
(unsigned comparison)
Status Affected:
None
Encoding:
=
=
=
After Instruction
REG
WREG
N
Z
=
=
=
=
13h
0ECh
1
0
001a
ffff
ffff
Compares the contents of data
memory location 'f' to the contents
of WREG by performing an
unsigned subtraction.
If 'f' = WREG, then the fetched
instruction is discarded and a NOP
is executed instead making this a
two-cycle instruction. If ’a’ is 0, the
Access Bank will be selected, overriding the BSR value. If ’a’ is 1, the
Bank will be selected as per the BSR
value.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Decode
13h
?
?
0110
f [,a]
Description:
Before Instruction
REG
N
Z
Compare f with WREG,
skip if f = WREG
CPFSEQ
Complement f
Q2
Q3
Q4
Read
register ’f’
Process
Data
No
operation
If skip:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
NEQUAL
EQUAL
CPFSEQ REG
:
:
Before Instruction
PC Address =
WREG
=
REG
=
After Instruction
If REG
=
PC
=
If REG
≠
PC
=
DS39541A-page 232
Advance Information
HERE
?
?
WREG;
Address (EQUAL)
WREG;
Address (NEQUAL)
 2001 Microchip Technology Inc.
PIC18C601/801
Compare f with WREG,
CPFSGT
Syntax:
[ label ] CPFSGT
Operands:
Compare f with WREG,
CPFSLT
skip if f > WREG
Syntax:
[ label ] CPFSLT
0 ≤ f ≤ 255
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(f) − (WREG),
skip if (f) > (WREG)
(unsigned comparison)
Operation:
(f) – (WREG),
skip if (f) < (WREG)
(unsigned comparison)
Status Affected:
None
Status Affected:
None
Encoding:
0110
010a
f [,a]
skip if f < WREG
ffff
ffff
Encoding:
0110
000a
f [,a]
ffff
ffff
Description:
Compares the contents of data
memory location ’f’ to the contents of
the WREG by performing an
unsigned subtraction.
If the contents of ’f’ are greater than
the contents of , then the fetched
instruction is discarded and a NOP
is executed instead, making this a
two-cycle instruction. If ’a’ is 0, the
Access Bank will be selected, overriding the BSR value. If ’a’ is 1, the
Bank will be selected as per the BSR
value.
Description:
Compares the contents of data
memory location 'f' to the contents
of WREG by performing an
unsigned subtraction.
If the contents of 'f' are less than the
contents of WREG, then the fetched
instruction is discarded and a NOP
is executed instead, making this a
two-cycle instruction. If ’a’ is 0, the
Access Bank will be selected. If ’a’ is
1, the Bank will be selected as per
the BSR value.
Words:
1
Words:
1
Cycles:
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Read
register ’f’
Process
Data
No
operation
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
Decode
If skip:
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
HERE
NGREATER
GREATER
CPFSGT REG
:
:
Q Cycle Activity:
Q1
Decode
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
HERE
NLESS
LESS
PC
WREG
Address (HERE)
?
CPFSLT REG
:
:
=
=
Address (HERE)
?
<
=
≥
=
WREG;
Address (LESS)
WREG;
Address (NLESS)
After Instruction
WREG;
Address (GREATER)
WREG;
Address (NGREATER)
 2001 Microchip Technology Inc.
Q4
No
operation
Before Instruction
Before Instruction
PC
=
WREG
=
After Instruction
If REG
>
PC
=
If REG
≤
PC
=
Q3
Process
Data
If skip:
Example:
Example:
Q2
Read
register ’f’
If REG
PC
If REG
PC
Advance Information
DS39541A-page 233
PIC18C601/801
DAW
Decimal Adjust WREG Register
DECF
Decrement f
Syntax:
[label] DAW
Syntax:
[ label ] DECF f [,d [,a]]
Operands:
None
Operands:
Operation:
If [WREG<3:0> >9] or [DC = 1] then
(WREG<3:0>) + 6 → W<3:0>;
else
(WREG<3:0>) → W<3:0>;
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) – 1 → dest
Status Affected:
C,DC,N,OV,Z
Encoding:
If [WREG<7:4> >9] or [C = 1] then
(WREG<7:4>) + 6 → WREG<7:4>;
else
(WREG<7:4>) → WREG<7:4>;
Status Affected:
0000
Description:
0000
1
Cycles:
1
Q Cycle Activity:
Q1
Q3
Q4
Read
register WREG
Process
Data
Write
WREG
Example1:
DAW
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Example:
DECF
CNT
Before Instruction
CNT
Z
=
=
01h
0
After Instruction
Before Instruction
=
=
=
ffff
Words:
Decode
Q2
ffff
Decrement register 'f'. If 'd' is 0, the
result is stored in WREG. If 'd' is 1,
the result is stored back in register 'f'
(default). If ’a’ is 0, the Access Bank
will be selected, overriding the BSR
value. If ’a’ is 1, the Bank will be
selected as per the BSR value.
0111
DAW adjusts the eight-bit value in
WREG resulting from the earlier
addition of two variables (each in
packed BCD format) and produces a
correct packed BCD result.
Words:
WREG
C
DC
0000
01da
Description:
C
Encoding:
Decode
0000
0A5h
0
0
CNT
Z
=
=
00h
1
After Instruction
WREG
C
DC
=
=
=
05h
1
0
Example 2:
Before Instruction
WREG
C
DC
=
=
=
0CEh
0
0
After Instruction
WREG
C
DC
=
=
=
DS39541A-page 234
34h
1
0
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
DECFSZ
Decrement f, skip if 0
DCFSNZ
Decrement f, skip if not 0
Syntax:
[ label ] DECFSZ f [,d [,a]]
Syntax:
[label] DCFSNZ f [,d [,a]]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) – 1 → dest,
skip if result = 0
Operation:
(f) – 1 → dest,
skip if result ≠ 0
Status Affected:
None
Status Affected:
None
Encoding:
0010
11da
ffff
ffff
Encoding:
0100
11da
ffff
ffff
Description:
The contents of register 'f' are decremented. If 'd' is 0, the result is
placed in WREG. If 'd' is 1, the result
is placed back in register 'f' (default).
If the result is 0, the next instruction,
which is already fetched, is discarded, and a NOP is executed
instead, making it a two-cycle
instruction. If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
Description:
The contents of register 'f' are decremented. If 'd' is 0, the result is
placed in WREG. If 'd' is 1, the result
is placed back in register 'f' (default).
If the result is not 0, the next instruction, which is already fetched, is
discarded, and a NOP is executed
instead, making it a two-cycle
instruction. If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
Words:
1
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
If skip:
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
If skip:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
DECFSZ
GOTO
CNT
LOOP
Example:
CONTINUE
Before Instruction
PC
=
=
=
=
≠
=
DCFSNZ
:
:
TEMP
Before Instruction
Address (HERE)
After Instruction
CNT
If CNT
PC
If CNT
PC
HERE
ZERO
NZERO
TEMP
=
?
=
=
=
≠
=
TEMP - 1,
0;
Address (ZERO)
0;
Address (NZERO)
After Instruction
CNT - 1
0;
Address (CONTINUE)
0;
Address (HERE+2)
 2001 Microchip Technology Inc.
TEMP
If TEMP
PC
If TEMP
PC
Advance Information
DS39541A-page 235
PIC18C601/801
GOTO
Unconditional Branch
INCF
Increment f
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 1048575
Operands:
Operation:
k → PC<20:1>
Status Affected:
None
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) + 1 → dest
Status Affected:
C,DC,N,OV,Z
Encoding:
1st word (k<7:0>)
2nd word(k<19:8>)
Description:
1110
1111
2
Cycles:
2
Q Cycle Activity:
Q1
No
operation
1111
k19kkk
k7kkk
kkkk
kkkk0
kkkk8
GOTO allows an unconditional
branch anywhere within entire 2M
byte memory range. The 20-bit
value ’k’ is loaded into PC<20:1>.
GOTO is always a two-cycle
instruction.
Words:
Decode
GOTO k
Q2
Q3
Q4
Read literal
’k’<7:0>,
No
operation
Read literal
’k’<19:8>,
Write to PC
No
operation
No
operation
Encoding:
0010
GOTO THERE
After Instruction
PC =
Address (THERE)
10da
ffff
ffff
Description:
The contents of register ’f’ are incremented. If ’d’ is 0, the result is placed
in WREG. If ’d’ is 1, the result is
placed back in register ’f’ (default). If
’a’ is 0, the Access Bank will be
selected, overriding the BSR value.
If ’a’ is 1, the Bank will be selected
as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
No
operation
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Example:
Example:
INCF f [,d [,a]]
INCF
CNT
Before Instruction
CNT
Z
C
DC
=
=
=
=
0FFh
0
?
?
After Instruction
CNT
Z
C
DC
DS39541A-page 236
Advance Information
=
=
=
=
00h
1
1
1
 2001 Microchip Technology Inc.
PIC18C601/801
INCFSZ
Increment f, skip if 0
INFSNZ
Increment f, skip if not 0
Syntax:
[ label ]
Syntax:
[label]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) + 1 → dest,
skip if result = 0
Operation:
(f) + 1 → dest,
skip if result ≠ 0
Status Affected:
None
Status Affected:
None
Encoding:
0011
INCFSZ f [,d [,a]]
11da
ffff
ffff
Encoding:
0100
INFSNZ f [,d [,a]]
10da
ffff
ffff
Description:
The contents of register ’f’ are incremented. If ’d’ is 0, the result is placed
in WREG. If ’d’ is 1, the result is
placed back in register ’f’ (default).
If the result is 0, the next instruction,
which is already fetched, is discarded, and a NOP is executed
instead, making it a two-cycle
instruction. If ’a’ is 0, the Access
Bank will be selected, overriding
the BSR value. If ’a’ is 1, the Bank
will be selected as per the BSR
value.
Description:
The contents of register 'f' are incremented. If 'd' is 0, the result is placed
in WREG. If 'd' is 1, the result is
placed back in register 'f' (default).
If the result is not 0, the next instruction, which is already fetched, is
discarded, and a NOP is executed
instead, making it a two-cycle
instruction. If ’a’ is 0, the Access
Bank will be selected, overriding
the BSR value. If ’a’ is 1, the Bank
will be selected as per the BSR
value.
Words:
1
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ’f’
Process
Data
Write to
destination
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
If skip:
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
If skip:
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
NZERO
ZERO
INCFSZ
:
:
Before Instruction
PC
=
=
=
=
≠
=
Example:
HERE
ZERO
NZERO
INFSNZ
REG
Before Instruction
Address (HERE)
After Instruction
CNT
If CNT
PC
If CNT
PC
CNT
PC
=
Address (HERE)
After Instruction
CNT + 1
0;
Address (ZERO)
0;
Address (NZERO)
 2001 Microchip Technology Inc.
REG
If REG
PC
If REG
PC
Advance Information
=
≠
=
=
=
REG + 1
0;
Address (NZERO)
0;
Address (ZERO)
DS39541A-page 237
PIC18C601/801
IORLW
Inclusive OR literal with WREG
IORWF
Inclusive OR WREG with f
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
(WREG) .OR. k → WREG
Status Affected:
N,Z
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(WREG) .OR. (f) → dest
Status Affected:
N,Z
Encoding:
0000
Description:
1001
kkkk
kkkk
The contents of WREG are OR’ed
with the eight bit literal 'k'. The result
is placed in WREG.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Example:
Q2
Q3
Q4
Read
literal ’k’
Process
Data
Write to
WREG
IORLW
Before Instruction
WREG
N
Z
IORLW k
=
=
=
9Ah
?
?
35h
Encoding:
0001
IORWF
00da
f [,d [,a]]
ffff
ffff
Description:
Inclusive OR WREG with register
'f'. If 'd' is 0, the result is placed in
WREG. If 'd' is 1, the result is
placed back in register 'f' (default).
If ’a’ is 0, the Access Bank will be
selected, overriding the BSR value.
If ’a’ is 1, the Bank will be selected
as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
After Instruction
WREG
N
Z
=
=
=
0BFh
1
0
Example:
IORWF
RESULT, W
Before Instruction
RESULT
WREG
N
Z
=
=
=
=
13h
91h
?
?
After Instruction
RESULT
WREG
N
Z
DS39541A-page 238
Advance Information
=
=
=
=
13h
93h
1
0
 2001 Microchip Technology Inc.
PIC18C601/801
LFSR
Load FSR
MOVF
Move f
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0≤f≤2
0 ≤ k ≤ 4095
Operands:
Operation:
k → FSRf
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Status Affected:
None
Operation:
f → dest
Status Affected:
N,Z
Encoding:
LFSR f,k
1110
1111
1110
0000
00ff
k7kkk
k11kkk
kkkk
Description:
The 12-bit literal ’k’ is loaded into
the file select register pointed to
by ’f’.
Words:
2
Cycles:
2
Q Cycle Activity:
Q1
Encoding:
Description:
0101
Q2
Q3
Q4
Read literal
’k’ MSB
Process
Data
Write
literal ’k’ MSB
to FSRfH
Words:
1
Decode
Read literal
’k’ LSB
Process
Data
Write literal ’k’
to FSRfL
Cycles:
1
Example:
After Instruction
FSR2H
FSR2L
Q Cycle Activity:
Q1
Decode
=
=
03h
0ABh
Example:
00da
ffff
ffff
The contents of register ’f’ is moved
to a destination dependent upon the
status of ’d’. If 'd' is 0, the result is
placed in WREG. If 'd' is 1, the result
is placed back in register 'f' (default).
Location 'f' can be anywhere in the
256 byte Bank. If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
Decode
LFSR FSR2, 3ABh
MOVF f [,d [,a]]
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write
WREG
MOVF
REG, W
Before Instruction
REG
WREG
N
Z
=
=
=
=
22h
0FFh
?
?
=
=
=
=
22h
22h
0
0
After Instruction
REG
WREG
N
Z
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 239
PIC18C601/801
MOVFF
Move f to f
MOVLB
Move literal to low nibble in BSR
Syntax:
[label]
Syntax:
[ label ]
Operands:
0 ≤ fs ≤ 4095
0 ≤ fd ≤ 4095
Operands:
0 ≤ k ≤ 255
Operation:
k → BSR
Operation:
(fs) → fd
Status Affected:
None
Status Affected:
None
Encoding:
Encoding:
1st word (source)
2nd word (destin.)
MOVFF fs,fd
1100
1111
Description:
ffff
ffff
ffff
ffff
ffffs
ffffd
The contents of source register ’fs’
are moved to destination register ’fd’.
Location of source ’fs’ can be anywhere in the 4096 byte data space
(000h to FFFh), and location of destination ’fd’ can also be anywhere from
000h to FFFh.
Either source or destination can be
WREG (a useful special situation).
MOVFF is particularly useful for
transferring a data memory location
to a peripheral register (such as the
transmit buffer or an I/O port).
The MOVFF instruction cannot use
the PCL, TOSU, TOSH or TOSL as
the destination register.
Words:
2
Cycles:
2 (3)
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ’f’
(src)
Process
Data
No
operation
Decode
No
operation
No
operation
Write
register ’f’
(dest)
No dummy
read
Example:
MOVFF
MOVLB k
0000
0001
kkkk
kkkk
Description:
The 8-bit literal ’k’ is loaded into
the Bank Select Register (BSR).
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Example:
Q2
Q3
Q4
Read literal
’k’
Process
Data
Write
literal ’k’ to
BSR
MOVLB
05h
Before Instruction
BSR register
=
02h
=
05h
After Instruction
BSR register
REG1, REG2
Before Instruction
REG1
REG2
=
=
33h
11h
=
=
33h,
33h
After Instruction
REG1
REG2
DS39541A-page 240
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
MOVLW
Move literal to WREG
MOVWF
Move WREG to f
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
k → WREG
0 ≤ f ≤ 255
a ∈ [0,1]
Status Affected:
None
Operation:
(WREG) → f
Status Affected:
None
Encoding:
0000
Description:
MOVLW k
1110
kkkk
The eight bit literal ’k’ is loaded into
WREG.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Example:
Q2
Q3
Q4
Read
literal ’k’
Process
Data
Write to
WREG
MOVLW
After Instruction
WREG
kkkk
=
0x5A
5Ah
Encoding:
0110
MOVWF
111a
f [,a]
ffff
ffff
Description:
Move data from WREG to register ’f’.
Location ’f’ can be anywhere in the
256 byte Bank. If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write
register ’f’
Example:
MOVWF
REG
Before Instruction
WREG
REG
=
=
4Fh
0FFh
After Instruction
WREG
REG
 2001 Microchip Technology Inc.
Advance Information
=
=
4Fh
4Fh
DS39541A-page 241
PIC18C601/801
MULLW
Multiply Literal with WREG
MULWF
Multiply WREG with f
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(WREG) x (f) → PRODH:PRODL
Status Affected:
None
MULLW
k
Operands:
0 ≤ k ≤ 255
Operation:
(WREG) x k → PRODH:PRODL
Status Affected:
None
Encoding:
Description:
0000
1
Cycles:
1
Q Cycle Activity:
Q1
Example:
kkkk
kkkk
An unsigned multiplication is
carried out between the contents
of WREG and the 8-bit literal ’k’.
The 16-bit result is placed in
PRODH:PRODL register pair.
PRODH contains the high byte.
WREG is unchanged.
None of the status flags are
affected.
Note that neither overflow nor
carry is possible in this operation.
A zero result is possible but not
detected.
Words:
Decode
1101
Q2
Q3
Q4
Read
literal ’k’
Process
Data
Write
registers
PRODH:
PRODL
MULLW
C4h
Before Instruction
WREG
PRODH
PRODL
=
=
=
0E2h
?
?
=
=
=
0E2h
0ADh
08h
Encoding:
MULWF
0000
001a
f [,a]
ffff
ffff
Description:
An unsigned multiplication is
carried out between the contents
of WREG and the register file
location ’f’. The 16-bit result is
stored in the PRODH:PRODL
register pair. PRODH contains
the high byte.
Both WREG and ’f’ are
unchanged.
None of the status flags are
affected.
Note that neither overflow nor
carry is possible in this operation.
A zero result is possible but not
detected. If ’a’ is 0, the Access
Bank will be selected, overriding
the BSR value. If ’a’ is 1, the
Bank will be selected as per the
BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write
registers
PRODH:
PRODL
After Instruction
WREG
PRODH
PRODL
Example:
MULWF
REG
Before Instruction
WREG
REG
PRODH
PRODL
=
=
=
=
0C4h
0B5h
?
?
=
=
=
=
0C4h
0B5h
8Ah
94h
After Instruction
WREG
REG
PRODH
PRODL
DS39541A-page 242
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
NEGF
Negate f
Syntax:
[label]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
NEGF
f [,a]
Operation:
(f)+1→f
Status Affected:
N,OV, C, DC, Z
Encoding:
0110
Description:
1
Cycles:
1
Q Cycle Activity:
Q1
Syntax:
[ label ]
NOP
Operands:
None
Operation:
No operation
Status Affected:
None
0000
1111
ffff
Description:
1
Cycles:
1
Decode
0000
xxxx
0000
xxxx
No operation.
Words:
Q Cycle Activity:
Q1
0000
xxxx
Q2
Q3
Q4
No
operation
No
operation
No
operation
Example:
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write
register ’f’
Example:
No Operation
Encoding:
ffff
Location ’f’ is negated using two’s
complement. The result is placed in
the data memory location 'f'. If ’a’ is
0, the Access Bank will be selected,
overriding the BSR value. If ’a’ is 1,
the Bank will be selected as per the
BSR value.
Words:
Decode
110a
NOP
NEGF
None.
REG
Before Instruction
REG
N
OV
C
DC
Z
=
=
=
=
=
=
0011 1010 [3Ah]
?
?
?
?
?
After Instruction
REG
N
OV
C
DC
Z
=
=
=
=
=
=
1100 0110 [0C6h]
1
0
0
0
0
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 243
PIC18C601/801
POP
Pop Top of Return Stack
PUSH
Push Top of Return Stack
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
None
Operands:
None
Operation:
(TOS) → bit bucket
Operation:
(PC+2) → TOS
Status Affected:
None
Status Affected:
None
Encoding:
0000
Description:
0000
0000
0110
The TOS value is pulled off the
return stack and is discarded. The
TOS value then becomes the previous value that was pushed onto the
return stack.
This instruction is provided to enable
the user to properly manage the
return stack to incorporate a software stack.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
POP
Encoding:
Description:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
No
operation
Pop TOS
value
No
operation
Example:
POP
GOTO
=
=
DS39541A-page 244
=
=
0101
Q2
Q3
Q4
Push PC+2
onto return
stack
No
operation
No
operation
PUSH
TOS
PC
0031A2h
014332h
After Instruction
TOS
PC
0000
Before Instruction
NEW
Before Instruction
TOS
Stack (1 level down)
0000
The PC+2 is pushed onto the top of
the return stack. The previous TOS
value is pushed down on the stack.
This instruction allows implementing
a software stack by modifying TOS,
and then push it onto the return
stack.
Words:
Decode
Example:
0000
PUSH
014332h
NEW
=
=
00345Ah
000124h
=
=
=
000126h
000126h
00345Ah
After Instruction
PC
TOS
Stack (1 level down)
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
RCALL
Relative Call
RESET
Reset
Syntax:
[ label ] RCALL
Syntax:
[ label ]
Operands:
Operation:
-1024 ≤ n ≤ 1023
Operands:
None
(PC) + 2 → TOS,
(PC) + 2 + 2n → PC
Operation:
Reset all registers and flags that are
affected by a MCLR Reset.
Status Affected:
None
Status Affected:
All
Encoding:
Description:
1101
nnnn
nnnn
Subroutine call with a jump up to 1K
from the current location. First,
return address (PC+2) is pushed
onto the stack. Then, add the 2’s
complement number ’2n’ to the PC.
Since the PC will have incremented
to fetch the next instruction, the new
address will be PC+2+2n. This
instruction is a two-cycle instruction.
Words:
1
Cycles:
2
Encoding:
0000
RESET
0000
1111
1111
Description:
This instruction provides a way to
execute a MCLR Reset in software.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Example:
Q2
Q3
Q4
Start
reset
No
operation
No
operation
RESET
After Instruction
Q Cycle Activity:
Q1
Decode
1nnn
n
Q2
Q3
Q4
Read literal
’n’
Process
Data
Write to PC
No
operation
No
operation
Registers =
Flags*
=
Reset Value
Reset Value
Push PC to
stack
No
operation
Example:
No
operation
HERE
RCALL Jump
Before Instruction
PC =
Address (HERE)
After Instruction
PC =
TOS =
Address (Jump)
Address (HERE+2)
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 245
PIC18C601/801
RETFIE
Return from Interrupt
RETLW
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
s ∈ [0,1]
Operands:
0 ≤ k ≤ 255
Operation:
(TOS) → PC,
1 → GIE/GIEH or PEIE/GIEL,
if s = 1
(WS) → WREG,
(STATUSS) → STATUS,
(BSRS) → BSR,
PCLATU, PCLATH are unchanged.
Operation:
k → W,
(TOS) → PC,
PCLATU, PCLATH are unchanged
Status Affected:
None
Status Affected:
0000
Description:
0000
0001
0000
Description:
1
Cycles:
2
Words:
1
Cycles:
2
Q Cycle Activity:
Q1
kkkk
kkkk
Q2
Q3
Q4
Read
literal ’k’
Process
Data
Pop PC from
stack, write to
WREG
No
operation
No
operation
No
operation
No
operation
Example:
Q2
Q3
Q4
No
operation
No
operation
Pop PC
from stack
Set GIEH or
GIEL
No
operation
Example:
1100
Decode
CALL TABLE
Q Cycle Activity:
Q1
RETLW k
W is loaded with the eight-bit literal
'k'. The program counter is loaded
from the top of the stack (the return
address). The high address latch
(PCLATH) remains unchanged.
000s
Return from Interrupt. Stack is
popped and Top-of-Stack (TOS) is
loaded into the PC. Interrupts are
enabled by setting the either the
high or low priority global interrupt
enable bit. If ’s’ = 1, the contents
of the shadow registers WS,
STATUSS and BSRS are loaded
into their corresponding registers,
WREG, STATUS and BSR. If
’s’ = 0, no update of these
registers occurs (default).
Words:
No
operation
Encoding:
None
Encoding:
Decode
RETFIE [s]
Return Literal to WREG
RETFIE
No
operation
No
operation
1
:
TABLE
ADDWF
RETLW
RETLW
:
:
RETLW
; WREG contains table
; offset value
; WREG now has
; table value
PCL
k0
k1
; WREG = offset
; Begin table
;
kn
; End of table
After Interrupt
PC
WREG
BSR
STATUS
GIE/GIEH, PEIE/GIEL
DS39541A-page 246
=
=
=
=
=
TOS
WS
BSRS
STATUSS
1
Before Instruction
WREG
=
07h
After Instruction
WREG
Advance Information
=
value of kn
 2001 Microchip Technology Inc.
PIC18C601/801
RETURN
Return from Subroutine
RLCF
Rotate Left f through Carry
Syntax:
[ label ]
Syntax:
[ label ] RLCF
RETURN [s]
f [,d [,a]]
Operands:
s ∈ [0,1]
Operands:
Operation:
(TOS) → PC,
if s = 1
(WS) → W,
(STATUSS) → STATUS,
(BSRS) → BSR,
PCLATU, PCLATH are unchanged
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f<n>) → dest<n+1>,
(f<7>) → C,
(C) → dest<0>
Status Affected:
C,N,Z
None
Encoding:
Status Affected:
Encoding:
0000
Description:
0000
0001
001s
0011
Description:
1
Words:
1
Cycles:
2
Cycles:
1
Q3
Q4
Decode
No
operation
Process
Data
Pop PC
from stack
No
operation
No
operation
No
operation
No
operation
Q Cycle Activity:
Q1
Decode
ffff
register f
C
Words:
Q2
ffff
The contents of register 'f' are
rotated one bit to the left through the
Carry Flag. If 'd' is 0 the result is
placed in WREG. If 'd' is 1 the result
is stored back in register 'f' (default).
If ’a’ is 0, the Access Bank will be
selected, overriding the BSR value.
If ’a’ is 1, the Bank will be selected
as per the BSR value.
Return from subroutine. The stack
is popped and the top of the stack
(TOS) is loaded into the program
counter. If ’s’ = 1, the contents of
the shadow registers WS, STATUSS and BSRS are loaded into
their corresponding registers,
WREG, STATUS and BSR. If
’s’ = 0, no update of these
registers occurs (default).
Q Cycle Activity:
Q1
01da
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Example:
RLCF
REG, W
Before Instruction
Example:
RETURN
After Call
PC
=
TOS
RETURN FAST
Before Instruction
WRG
=
STATUS =
BSR
=
04h
00h
00h
REG
C
N
Z
=
=
=
=
1110 0110
0
?
?
After Instruction
REG
WREG
C
N
Z
=
=
=
=
=
1110 0110
1100 1100
1
1
0
After Instruction
WREG
STATUS
BSR
PC
=
=
=
=
04h
00h
00h
TOS
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 247
PIC18C601/801
RLNCF
Rotate Left f (no carry)
RRCF
Rotate Right f through Carry
Syntax:
[ label ] RLNCF
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f<n>) → dest<n+1>,
(f<7>) → dest<0>
Operation:
Status Affected:
N,Z
(f<n>) → dest<n-1>,
(f<0>) → C,
(C) → dest<7>
Status Affected:
C,N,Z
Encoding:
0100
Description:
01da
f [,d [,a]]
ffff
ffff
The contents of register ’f’ are
rotated one bit to the left. If ’d’ is 0
the result is placed in WREG. If ’d’ is
1, the result is stored back in register
'f' (default). If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
Encoding:
0011
Description:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
RLNCF
REG
ffff
ffff
register f
C
Q2
Example:
00da
The contents of register 'f' are
rotated one bit to the right through
the Carry Flag. If 'd' is 0, the result is
placed in WREG. If 'd' is 1, the result
is placed back in register 'f' (default).
If ’a’ is 0, the Access Bank will be
selected, overriding the BSR value.
If ’a’ is 1, the Bank will be selected
as per the BSR value.
register f
Words:
RRCF f [,d [,a]]
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Before Instruction
REG
N
Z
=
=
=
1010 1011
?
?
After Instruction
REG
N
Z
=
=
=
DS39541A-page 248
0101 0111
0
0
Example:
RRCF
REG, W
Before Instruction
REG
C
N
Z
=
=
=
=
1110 0110
0
?
?
After Instruction
REG
WREG
C
N
Z
Advance Information
=
=
=
=
=
1110 0110
0111 0011
0
0
0
 2001 Microchip Technology Inc.
PIC18C601/801
RRNCF
Rotate Right f (no carry)
SETF
Set f
Syntax:
[ label ]
Syntax:
[label] SETF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(f<n>) → dest<n-1>,
(f<0>) → dest<7>
FFh → f
Operation:
Status Affected:
None
Status Affected:
N,Z
Encoding:
0100
Description:
RRNCF f [,d [,a]]
00da
Encoding:
ffff
ffff
The contents of register ’f’ are
rotated one bit to the right. If ’d’ is 0,
the result is placed in WREG. If ’d’ is
1, the result is placed back in register 'f' (default). If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
register f
Words:
1
Cycles:
1
100a
ffff
ffff
Description:
The contents of the specified register
are set to FFh. If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Example:
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write
register ’f’
SETF
REG
Before Instruction
Q Cycle Activity:
Q1
Decode
0110
f [,a]
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Example 1:
RRNCF
REG
=
5Ah
=
0FFh
After Instruction
REG
REG
Before Instruction
REG
N
Z
=
=
=
1101 0111
?
?
After Instruction
REG
N
Z
=
=
=
Example 2:
1110 1011
1
0
RRNCF
REG, 0, 0
Before Instruction
WREG
REG
N
Z
=
=
=
=
?
1101 0111
?
?
After Instruction
WREG
REG
N
Z
=
=
=
=
1110 1011
1101 0111
1
0
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 249
PIC18C601/801
SLEEP
Enter SLEEP mode
SUBFWB
Subtract f from WREG with borrow
Syntax:
[ label ] SLEEP
Syntax:
[ label ] SUBFWB f [,d [,a]]
Operands:
None
Operands:
Operation:
00h → WDT,
0 → WDT postscaler,
1 → TO,
0 → PD
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(WREG) – (f) – (C) → dest
Status Affected:
N,OV, C, DC, Z
TO, PD
Encoding:
Status Affected:
Encoding:
0000
0000
0000
0011
Description:
The power-down status bit (PD) is
cleared. The time-out status bit
(TO) is set. Watchdog Timer and
its postscaler are cleared.
The processor is put into SLEEP
mode with the oscillator stopped.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
No
operation
Process
Data
Go to
sleep
01da
ffff
ffff
Description:
Subtract register 'f' and carry flag
(borrow) from WREG (2’s complement method). If 'd' is 0, the result is
stored in WREG. If 'd' is 1, the result
is stored in register 'f' (default) . If ’a’
is 0, the Access Bank will be
selected, overriding the BSR value.
If ’a’ is 1, the Bank will be selected
as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Example:
0101
SLEEP
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Before Instruction
TO =
PD =
?
?
After Instruction
TO =
PD =
1†
0
† If WDT causes wake-up, this bit is cleared.
DS39541A-page 250
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
SUBFWB (Cont.)
Example 1:
SUBFWB
REG
Before Instruction
REG
WREG
C
=
=
=
3
2
1
After Instruction
REG
WREG
C
Z
N
0FFh
2
0
0
1 ; result is negative
SUBFWB
REG
=
=
=
2
5
1
2
3
1
0
0
; result is positive
REG
1
2
0
=
=
=
=
=
Status Affected:
N,OV, C, DC, Z
0000
0
2
1
1
0
1000
kkkk
kkkk
Description:
WREG is subtracted from the eight
bit literal 'k'. The result is placed in
WREG.
Words:
1
Cycles:
1
Q2
Q3
Q4
Read
literal ’k’
Process
Data
Write to
WREG
SUBLW
=
=
02h
1
?
After Instruction
WREG
C
Z
N
=
=
=
=
Example 2:
After Instruction
REG
WREG
C
Z
N
k – (WREG) → WREG
WREG
C
SUBFWB
=
=
=
0 ≤ k ≤ 255
Operation:
Before Instruction
Before Instruction
REG
WREG
C
Operands:
Example 1:
=
=
=
=
=
Example 3:
[ label ] SUBLW k
Decode
After Instruction
REG
WREG
C
Z
N
Syntax:
Q Cycle Activity:
Q1
Before Instruction
REG
WREG
C
Subtract WREG from literal
Encoding:
=
=
=
=
=
Example 2:
SUBLW
1
1
0
0
SUBLW
; result is positive
02h
Before Instruction
WREG
C
; result is zero
=
=
2
?
After Instruction
WREG
C
Z
N
=
=
=
=
Example 3:
0
1
1
0
SUBLW
; result is zero
02h
Before Instruction
WREG
C
=
=
3
?
After Instruction
WREG
C
Z
N
 2001 Microchip Technology Inc.
Advance Information
=
=
=
=
0FFh ; (2’s complement)
0
; result is negative
0
1
DS39541A-page 251
PIC18C601/801
SUBWF
Syntax:
Subtract WREG from f
[ label ] SUBWF f [,d [,a]]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
(f) – (WREG) → dest
Status Affected:
N,OV, C, DC, Z
0101
Description:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
11da
REG
WREG
C
REG
=
=
=
3
2
?
After Instruction
ffff
ffff
Subtract WREG from register 'f'
(2’s complement method). If 'd' is 0,
the result is stored in WREG. If 'd'
is 1, the result is stored back in register 'f' (default). If ’a’ is 0, the
Access Bank will be selected, overriding the BSR value. If ’a’ is 1, the
Bank will be selected as per the
BSR value.
Words:
SUBWF
Before Instruction
Operation:
Encoding:
SUBWF (Cont.)
Example 1:
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
REG
WREG
C
Z
N
=
=
=
=
=
Example 2:
1
2
1
0
0
; result is positive
SUBWF
REG, W
Before Instruction
REG
WREG
C
=
=
=
2
2
?
After Instruction
REG
WREG
C
Z
N
=
=
=
=
=
Example 3:
2
0
1
1
0
; result is zero
SUBWF
REG
Before Instruction
REG
WREG
C
=
=
=
1
2
?
After Instruction
REG
WREG
C
Z
N
DS39541A-page 252
Advance Information
=
=
=
=
=
0FFh ;(2’s complement)
2
0 ; result is negative
0
1
 2001 Microchip Technology Inc.
PIC18C601/801
SUBWFB
Subtract WREG from f with
Borrow
SUBWFB (Cont.)
Syntax:
[ label ] SUBWFB f [,d [,a]]
Example 1:
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) – (WREG) – (C) → dest
Status Affected:
N,OV, C, DC, Z
Encoding:
Description:
0101
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
REG
Before Instruction
10da
ffff
REG
WREG
C
=
=
=
19h
0Dh
1
(0001 1001)
(0000 1101)
0Ch
0Dh
1
0
0
(0000 1011)
(0000 1101)
After Instruction
ffff
Subtract WREG and the carry flag
(borrow) from register 'f' (2’s complement method). If 'd' is 0, the
result is stored in WREG. If 'd' is 1,
the result is stored back in register
'f' (default). If ’a’ is 0, the Access
Bank will be selected, overriding
the BSR value. If ’a’ is 1, the Bank
will be selected as per the BSR
value.
Words:
SUBWFB
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
REG
WREG
C
Z
N
=
=
=
=
=
Example 2:
SUBWFB
; result is positive
REG, W
Before Instruction
REG
WREG
C
=
=
=
1Bh
1Ah
0
(0001 1011)
(0001 1010)
1Bh
00h
1
1
0
(0001 1011)
After Instruction
REG
WREG
C
Z
N
=
=
=
=
=
Example 3:
SUBWFB
; result is zero
REG
Before Instruction
REG
WREG
C
=
=
=
03h
0Eh
1
(0000 0011)
(0000 1101)
After Instruction
REG
WREG
C
Z
N
 2001 Microchip Technology Inc.
Advance Information
=
=
=
=
=
0F5h
0Eh
0
0
1
(1111 0100) [2’s comp]
(0000 1101)
; result is negative
DS39541A-page 253
PIC18C601/801
SWAPF
Swap nibbles in f
Syntax:
[ label ] SWAPF f [,d [,a]]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f<3:0>) → dest<7:4>,
(f<7:4>) → dest<3:0>
Status Affected:
None
Encoding:
0011
10da
ffff
ffff
Description:
The upper and lower nibbles of register ’f’ are exchanged. If ’d’ is 0, the
result is placed in WREG. If ’d’ is 1,
the result is placed in register ’f’
(default). If ’a’ is 0, the Access Bank
will be selected, overriding the BSR
value. If ’a’ is 1, the Bank will be
selected as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
Write to
destination
Example:
SWAPF
REG
Before Instruction
REG
=
53h
After Instruction
REG
=
DS39541A-page 254
35h
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TBLRD
Table Read
TBLRD (Cont.)
Syntax:
[ label ]
Example 1:
TBLRD ( *; *+; *-; +*)
None
Operation:
if TBLRD *,
(Prog Mem (TBLPTR)) → TABLAT;
TBLPTR - No Change;
if TBLRD *+,
(Prog Mem (TBLPTR)) → TABLAT;
(TBLPTR) +1 → TBLPTR;
if TBLRD *-,
(Prog Mem (TBLPTR)) → TABLAT;
(TBLPTR) -1 → TBLPTR;
if TBLRD +*,
(TBLPTR) +1 → TBLPTR;
(Prog Mem (TBLPTR)) → TABLAT;
Description:
TABLAT
TBLPTR
MEMORY(00A356h)
=
=
=
55h
00A356h
34h
=
=
34h
00A357h
After Instruction
TABLAT
TBLPTR
Example 2:
TBLRD
+* ;
Before Instruction
TABLAT
TBLPTR
MEMORY(01A357h)
MEMORY(01A358h)
=
=
=
=
0AAh
01A357h
12h
34h
=
=
34h
01A358h
After Instruction
None
Encoding:
*+ ;
Before Instruction
Operands:
Status Affected:
TBLRD
0000
0000
0000
10nn
nn=0 *
=1 *+
=2 *=3 +*
TABLAT
TBLPTR
This instruction is used to read the contents of Program Memory (P.M.). To
address the program memory, a pointer
called Table Pointer (TBLPTR) is used.
The TBLPTR (a 21-bit pointer) points to
each byte in the program memory.
TBLPTR has a 2 Mbyte address range.
TBLPTR[0] = 0: Least Significant
Byte of Program
Memory Word
TBLPTR[0] = 1: Most Significant
Byte of Program
Memory Word
The TBLRD instruction can modify the
value of TBLPTR as follows:
• no change
• post-increment
• post-decrement
• pre-increment
Words:
1
Cycles:
2
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No
operation
No
operation
No
operation
No
operation
No
operation
(Read
Program
Memory)
No
operation
No
operation
(Write
 2001 Microchip Technology Inc.
TABLAT)
Advance Information
DS39541A-page 255
PIC18C601/801
TBLWT
Table Write
TBLWT (Cont.)
Syntax:
[ label ]
Example 1:
TBLWT ( *; *+; *-; +*)
None
Operation:
if TBLWT*,
(TABLAT) → Prog Mem (TBLPTR) or
Holding Register;
TBLPTR - No Change;
if TBLWT*+,
(TABLAT) → Prog Mem (TBLPTR) or
Holding Register;
(TBLPTR) +1 → TBLPTR;
if TBLWT*-,
(TABLAT) → Prog Mem (TBLPTR) or
Holding Register;
(TBLPTR) -1 → TBLPTR;
if TBLWT+*,
(TBLPTR) +1 → TBLPTR;
(TABLAT) → Prog Mem (TBLPTR) or
Holding Register;
None
Encoding:
0000
Description:
*+;
Before Instruction
Operands:
Status Affected:
TBLWT
0000
0000
TABLAT
TBLPTR
MEMORY(00A356h)
=
=
=
55h
00A356h
0FFh
After Instructions (table write completion)
TABLAT
TBLPTR
MEMORY(00A356h)
Example 2:
TBLWT
=
=
=
55h
00A357h
55h
+*;
Before Instruction
TABLAT
TBLPTR
MEMORY(01389Ah)
MEMORY(01389Bh)
=
=
=
=
34h
01389Ah
0FFh
0FFh
After Instruction (table write completion)
TABLAT
TBLPTR
MEMORY(01389Ah)
MEMORY(01389Bh)
=
=
=
=
34h
01389Bh
0FFh
34h
11nn
nn=0 *
=1 *+
=2 *=3 +*
This instruction is used to program the
contents of Program Memory (P.M.).
The TBLPTR (a 21-bit pointer) points to
each byte in the program memory.
TBLPTR has a 2 MByte address range.
The LSb of the TBLPTR selects which
byte of the program memory location to
access.
TBLPTR[0] = 0:Least Significant
Byte of Program
Memory Word
TBLPTR[0] = 1:Most Significant
Byte of Program
Memory Word
The TBLWT instruction can modify the
value of TBLPTR as follows:
• no change
• post-increment
• post-decrement
• pre-increment
Words:
1
Cycles:
2 (many if long write is to on-chip
EPROM program memory)
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
No
operation
No
operation
No
operation
No operation
No
No operation
No
operation
(Read
operation
(Write to Holding
TABLAT)
Register or Memory)
DS39541A-page 256
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
TSTFSZ
Test f, skip if 0
XORLW
Exclusive OR literal with WREG
Syntax:
[ label ] TSTFSZ f [,a]
Syntax:
[ label ] XORLW k
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operands:
0 ≤ k ≤ 255
Operation:
skip if f = 0
Operation:
(WREG) .XOR. k → WREG
Status Affected:
None
Status Affected:
N,Z
Encoding:
Description:
Encoding:
0110
011a
ffff
ffff
If ’f’ = 0, the next instruction, fetched
during the current instruction execution, is discarded and a NOP is
executed, making this a two-cycle
instruction. If ’a’ is 0, the Access
Bank will be selected, overriding the
BSR value. If ’a’ is 1, the Bank will
be selected as per the BSR value.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read
register ’f’
Process
Data
No
operation
If skip:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
HERE
NZERO
ZERO
TSTFSZ
:
:
Description:
1010
kkkk
kkkk
The contents of WREG are
XOR’ed with the 8-bit literal 'k'. The
result is placed in WREG.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Decode
Q3
Read
literal ’k’
Example:
Q4
Process
Data
Write to
WREG
XORLW 0AFh
Before Instruction
WREG
N
Z
=
=
=
0B5h
?
?
After Instruction
WREG
N
Z
=
=
=
1Ah
0
0
Q4
No
operation
Example:
0000
CNT
Before Instruction
PC
=
Address (HERE)
=
=
≠
=
00h,
Address (ZERO)
00h,
Address (NZERO)
After Instruction
If CNT
PC
If CNT
PC
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 257
PIC18C601/801
XORWF
Exclusive OR WREG with f
Syntax:
[ label ] XORWF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(WREG) .XOR. (f) → dest
Status Affected:
N,Z
Encoding:
0001
10da
f [,d [,a]]
ffff
ffff
Description:
Exclusive OR the contents of WREG
with register ’f’. If ’d’ is 0, the result is
stored in WREG. If ’d’ is 1, the result
is stored back in the register ’f’
(default). If ’a’ is 0, the Access Bank
will be selected, overriding the BSR
value. If ’a’ is 1, the Bank will be
selected as per the BSR value.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Decode
Q3
Read
register ’f’
Example:
XORWF
Process
Data
Q4
Write to
destination
REG
Before Instruction
REG
WREG
N
Z
=
=
=
=
0AFh
0B5h
?
?
After Instruction
REG
WREG
N
Z
=
=
=
=
DS39541A-page 258
1Ah
0B5h
0
0
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
21.0
DEVELOPMENT SUPPORT
The PICmicro® microcontrollers are supported with a
full range of hardware and software development tools:
• Integrated Development Environment
- MPLAB® IDE Software
• Assemblers/Compilers/Linkers
- MPASMTM Assembler
- MPLAB C17 and MPLAB C18 C Compilers
- MPLINKTM Object Linker/
MPLIBTM Object Librarian
• Simulators
- MPLAB SIM Software Simulator
• Emulators
- MPLAB ICE 2000 In-Circuit Emulator
- ICEPIC™ In-Circuit Emulator
• In-Circuit Debugger
- MPLAB ICD for PIC16F87X
• Device Programmers
- PRO MATE® II Universal Device Programmer
- PICSTART® Plus Entry-Level Development
Programmer
• Low Cost Demonstration Boards
- PICDEMTM 1 Demonstration Board
- PICDEM 2 Demonstration Board
- PICDEM 3 Demonstration Board
- PICDEM 17 Demonstration Board
- KEELOQ® Demonstration Board
21.1
MPLAB Integrated Development
Environment Software
The MPLAB IDE software brings an ease of software
development previously unseen in the 8-bit microcontroller market. The MPLAB IDE is a Windows®-based
application that contains:
• An interface to debugging tools
- simulator
- programmer (sold separately)
- emulator (sold separately)
- in-circuit debugger (sold separately)
• A full-featured editor
• A project manager
• Customizable toolbar and key mapping
• A status bar
• On-line help
 2001 Microchip Technology Inc.
The MPLAB IDE allows you to:
• Edit your source files (either assembly or ‘C’)
• One touch assemble (or compile) and download
to PICmicro emulator and simulator tools (automatically updates all project information)
• Debug using:
- source files
- absolute listing file
- machine code
The ability to use MPLAB IDE with multiple debugging
tools allows users to easily switch from the costeffective simulator to a full-featured emulator with
minimal retraining.
21.2
MPASM Assembler
The MPASM assembler is a full-featured universal
macro assembler for all PICmicro MCU’s.
The MPASM assembler has a command line interface
and a Windows shell. It can be used as a stand-alone
application on a Windows 3.x or greater system, or it
can be used through MPLAB IDE. The MPASM assembler generates relocatable object files for the MPLINK
object linker, Intel® standard HEX files, MAP files to
detail memory usage and symbol reference, an absolute LST file that contains source lines and generated
machine code, and a COD file for debugging.
The MPASM assembler features include:
• Integration into MPLAB IDE projects.
• User-defined macros to streamline assembly
code.
• Conditional assembly for multi-purpose source
files.
• Directives that allow complete control over the
assembly process.
21.3
MPLAB C17 and MPLAB C18
C Compilers
The MPLAB C17 and MPLAB C18 Code Development
Systems are complete ANSI ‘C’ compilers for
Microchip’s PIC17CXXX and PIC18CXXX family of
microcontrollers, respectively. These compilers provide
powerful integration capabilities and ease of use not
found with other compilers.
For easier source level debugging, the compilers provide symbol information that is compatible with the
MPLAB IDE memory display.
Advance Information
DS39541A-page 259
PIC18C601/801
21.4
MPLINK Object Linker/
MPLIB Object Librarian
21.6
The MPLINK object linker combines relocatable
objects created by the MPASM assembler and the
MPLAB C17 and MPLAB C18 C compilers. It can also
link relocatable objects from pre-compiled libraries,
using directives from a linker script.
The MPLIB object librarian is a librarian for precompiled code to be used with the MPLINK object
linker. When a routine from a library is called from
another source file, only the modules that contain that
routine will be linked in with the application. This allows
large libraries to be used efficiently in many different
applications. The MPLIB object librarian manages the
creation and modification of library files.
The MPLINK object linker features include:
• Integration with MPASM assembler and MPLAB
C17 and MPLAB C18 C compilers.
• Allows all memory areas to be defined as sections
to provide link-time flexibility.
The MPLIB object librarian features include:
• Easier linking because single libraries can be
included instead of many smaller files.
• Helps keep code maintainable by grouping
related modules together.
• Allows libraries to be created and modules to be
added, listed, replaced, deleted or extracted.
21.5
MPLAB SIM Software Simulator
The MPLAB SIM software simulator allows code development in a PC-hosted environment by simulating the
PICmicro series microcontrollers on an instruction
level. On any given instruction, the data areas can be
examined or modified and stimuli can be applied from
a file, or user-defined key press, to any of the pins. The
execution can be performed in single step, execute
until break, or trace mode.
MPLAB ICE High Performance
Universal In-Circuit Emulator with
MPLAB IDE
The MPLAB ICE universal in-circuit emulator is intended
to provide the product development engineer with a
complete microcontroller design tool set for PICmicro
microcontrollers (MCUs). Software control of the
MPLAB ICE in-circuit emulator is provided by the
MPLAB Integrated Development Environment (IDE),
which allows editing, building, downloading and source
debugging from a single environment.
The MPLAB ICE 2000 is a full-featured emulator system with enhanced trace, trigger and data monitoring
features. Interchangeable processor modules allow the
system to be easily reconfigured for emulation of different processors. The universal architecture of the
MPLAB ICE in-circuit emulator allows expansion to
support new PICmicro microcontrollers.
The MPLAB ICE in-circuit emulator system has been
designed as a real-time emulation system, with
advanced features that are generally found on more
expensive development tools. The PC platform and
Microsoft® Windows environment were chosen to best
make these features available to you, the end user.
21.7
ICEPIC In-Circuit Emulator
The ICEPIC low cost, in-circuit emulator is a solution
for the Microchip Technology PIC16C5X, PIC16C6X,
PIC16C7X and PIC16CXXX families of 8-bit OneTime-Programmable (OTP) microcontrollers. The modular system can support different subsets of PIC16C5X
or PIC16CXXX products through the use of interchangeable personality modules, or daughter boards.
The emulator is capable of emulating without target
application circuitry being present.
The MPLAB SIM simulator fully supports symbolic debugging using the MPLAB C17 and the MPLAB C18 C compilers and the MPASM assembler. The software simulator
offers the flexibility to develop and debug code outside of
the laboratory environment, making it an excellent multiproject software development tool.
DS39541A-page 260
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
21.8
MPLAB ICD In-Circuit Debugger
Microchip’s In-Circuit Debugger, MPLAB ICD, is a powerful, low cost, run-time development tool. This tool is
based on the FLASH PIC16F87X and can be used to
develop for this and other PICmicro microcontrollers
from the PIC16CXXX family. The MPLAB ICD utilizes
the in-circuit debugging capability built into the
PIC16F87X. This feature, along with Microchip’s
In-Circuit Serial ProgrammingTM protocol, offers costeffective in-circuit FLASH debugging from the graphical
user interface of the MPLAB Integrated Development
Environment. This enables a designer to develop and
debug source code by watching variables, singlestepping and setting break points. Running at full
speed enables testing hardware in real-time.
21.9
PRO MATE II Universal Device
Programmer
The PRO MATE II universal device programmer is a
full-featured programmer, capable of operating in
stand-alone mode, as well as PC-hosted mode. The
PRO MATE II device programmer is CE compliant.
The PRO MATE II device programmer has programmable VDD and VPP supplies, which allow it to verify
programmed memory at VDD min and VDD max for maximum reliability. It has an LCD display for instructions
and error messages, keys to enter commands and a
modular detachable socket assembly to support various
package types. In stand-alone mode, the PRO MATE II
device programmer can read, verify, or program
PICmicro devices. It can also set code protection in this
mode.
21.10 PICSTART Plus Entry Level
Development Programmer
The PICSTART Plus development programmer is an
easy-to-use, low cost, prototype programmer. It connects to the PC via a COM (RS-232) port. MPLAB
Integrated Development Environment software makes
using the programmer simple and efficient.
The PICSTART Plus development programmer supports all PICmicro devices with up to 40 pins. Larger pin
count devices, such as the PIC16C92X and
PIC17C76X, may be supported with an adapter socket.
The PICSTART Plus development programmer is CE
compliant.
 2001 Microchip Technology Inc.
21.11 PICDEM 1 Low Cost PICmicro
Demonstration Board
The PICDEM 1 demonstration board is a simple board
which demonstrates the capabilities of several of
Microchip’s microcontrollers. The microcontrollers supported are: PIC16C5X (PIC16C54 to PIC16C58A),
PIC16C61, PIC16C62X, PIC16C71, PIC16C8X,
PIC17C42, PIC17C43 and PIC17C44. All necessary
hardware and software is included to run basic demo
programs. The user can program the sample microcontrollers provided with the PICDEM 1 demonstration
board on a PRO MATE II device programmer, or a
PICSTART Plus development programmer, and easily
test firmware. The user can also connect the
PICDEM 1 demonstration board to the MPLAB ICE incircuit emulator and download the firmware to the emulator for testing. A prototype area is available for the
user to build some additional hardware and connect it
to the microcontroller socket(s). Some of the features
include an RS-232 interface, a potentiometer for simulated analog input, push button switches and eight
LEDs connected to PORTB.
21.12 PICDEM 2 Low Cost PIC16CXX
Demonstration Board
The PICDEM 2 demonstration board is a simple demonstration board that supports the PIC16C62,
PIC16C64, PIC16C65, PIC16C73 and PIC16C74
microcontrollers. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample
microcontrollers provided with the PICDEM 2 demonstration board on a PRO MATE II device programmer,
or a PICSTART Plus development programmer, and
easily test firmware. The MPLAB ICE in-circuit emulator may also be used with the PICDEM 2 demonstration
board to test firmware. A prototype area has been provided to the user for adding additional hardware and
connecting it to the microcontroller socket(s). Some of
the features include a RS-232 interface, push button
switches, a potentiometer for simulated analog input, a
serial EEPROM to demonstrate usage of the I2CTM bus
and separate headers for connection to an LCD
module and a keypad.
Advance Information
DS39541A-page 261
PIC18C601/801
21.13 PICDEM 3 Low Cost PIC16CXXX
Demonstration Board
The PICDEM 3 demonstration board is a simple demonstration board that supports the PIC16C923 and
PIC16C924 in the PLCC package. It will also support
future 44-pin PLCC microcontrollers with an LCD Module. All the necessary hardware and software is
included to run the basic demonstration programs. The
user can program the sample microcontrollers provided with the PICDEM 3 demonstration board on a
PRO MATE II device programmer, or a PICSTART Plus
development programmer with an adapter socket, and
easily test firmware. The MPLAB ICE in-circuit emulator may also be used with the PICDEM 3 demonstration
board to test firmware. A prototype area has been provided to the user for adding hardware and connecting it
to the microcontroller socket(s). Some of the features
include a RS-232 interface, push button switches, a
potentiometer for simulated analog input, a thermistor
and separate headers for connection to an external
LCD module and a keypad. Also provided on the
PICDEM 3 demonstration board is a LCD panel, with 4
commons and 12 segments, that is capable of displaying time, temperature and day of the week. The
PICDEM 3 demonstration board provides an additional
RS-232 interface and Windows software for showing
the demultiplexed LCD signals on a PC. A simple serial
interface allows the user to construct a hardware
demultiplexer for the LCD signals.
DS39541A-page 262
21.14 PICDEM 17 Demonstration Board
The PICDEM 17 demonstration board is an evaluation
board that demonstrates the capabilities of several
Microchip microcontrollers, including PIC17C752,
PIC17C756A, PIC17C762 and PIC17C766. All necessary hardware is included to run basic demo programs,
which are supplied on a 3.5-inch disk. A programmed
sample is included and the user may erase it and
program it with the other sample programs using the
PRO MATE II device programmer, or the PICSTART
Plus development programmer, and easily debug and
test the sample code. In addition, the PICDEM 17 demonstration board supports downloading of programs to
and executing out of external FLASH memory on board.
The PICDEM 17 demonstration board is also usable
with the MPLAB ICE in-circuit emulator, or the
PICMASTER emulator and all of the sample programs
can be run and modified using either emulator. Additionally, a generous prototype area is available for user
hardware.
21.15 KEELOQ Evaluation and
Programming Tools
KEELOQ evaluation and programming tools support
Microchip’s HCS Secure Data Products. The HCS evaluation kit includes a LCD display to show changing
codes, a decoder to decode transmissions and a programming interface to program test transmitters.
Advance Information
 2001 Microchip Technology Inc.
Software Tools
Programmers Debugger Emulators
 2001 Microchip Technology Inc.
á
PIC17C7XX
á á
á á
á
á
PIC17C4X
á á
á á
á
á
PIC16C9XX
á
á á
á
á
PIC16F8XX
á
á á
á
á
PIC16C8X
á
á á
á
á
á
PIC16C7XX
á
á á
á
á
á
PIC16C7X
á
á á
á
á
á
PIC16F62X
á
á á
PIC16CXXX
á
á á
á
PIC16C6X
á
á á
á
PIC16C5X
á
á á
á
PIC14000
á
á á
PIC12CXXX
á
á á
á
á
á
á
á
á
á
á
á
á
á
á
Advance Information
MCRFXXX
á á
á
á
á
á
á
á
á
á
MCP2510
á
* Contact the Microchip Technology Inc. web site at www.microchip.com for information on how to use the MPLAB® ICD In-Circuit Debugger (DV164001) with PIC16C62, 63, 64, 65, 72, 73, 74, 76, 77.
** Contact Microchip Technology Inc. for availability date.
† Development tool is available on select devices.
MCP2510 CAN Developer’s Kit
á
13.56 MHz Anticollision
microIDTM Developer’s Kit
á á
125 kHz Anticollision microIDTM
Developer’s Kit
125 kHz microIDTM
Developer’s Kit
microIDTM Programmer’s Kit
KEELOQ® Transponder Kit
KEELOQ® Evaluation Kit
á
á
PICDEMTM 17 Demonstration
Board
á
á
PICDEMTM 14A Demonstration
Board
á
á
PICDEMTM 3 Demonstration
Board
á
†
á
†
24CXX/
25CXX/
93CXX
á
PICDEMTM 2 Demonstration
Board
á
†
HCSXXX
á
PICDEMTM 1 Demonstration
Board
á
**
á
PRO MATE® II
Universal Device Programmer
**
*
á
*
á á á
**
PIC18CXX2
á
PICSTART® Plus Entry Level
Development Programmer
MPLAB® ICD In-Circuit
Debugger
ICEPICTM In-Circuit Emulator
MPLAB® ICE In-Circuit Emulator
MPASMTM Assembler/
MPLINKTM Object Linker
MPLAB® C18 C Compiler
MPLAB® C17 C Compiler
TABLE 21-1:
Demo Boards and Eval Kits
MPLAB® Integrated
Development Environment
PIC18C601/801
DEVELOPMENT TOOLS FROM MICROCHIP
DS39541A-page 263
PIC18C601/801
NOTES:
DS39541A-page 264
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
22.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings(†)
Ambient temperature under bias.............................................................................................................-55°C to +125°C
Storage temperature .............................................................................................................................. -65°C to +150°C
Voltage on any pin with respect to VSS (except VDD, MCLR, and RA4) ......................................... -0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ......................................................................................................... -0.3V to +7.5V
Voltage on MCLR with respect to VSS (Note 2) ......................................................................................... 0V to +13.25V
Voltage on RA4 with respect to VSS ............................................................................................................... 0V to +8.5V
Total power dissipation (Note 1) ...............................................................................................................................1.0W
Maximum current out of VSS pin ...........................................................................................................................300 mA
Maximum current into VDD pin ..............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD)...................................................................................................................... ±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD) .............................................................................................................. ±20 mA
Maximum output current sunk by any I/O pin..........................................................................................................25 mA
Maximum output current sourced by any I/O pin ....................................................................................................25 mA
Maximum current sunk by all ports (combined) ....................................................................................................200 mA
Maximum current sourced by all ports (combined) ...............................................................................................200 mA
Note 1: Power dissipation is calculated as follows:
Pdis = VDD x {IDD - ∑ IOH} + ∑ {(VDD-VOH) x IOH} + ∑(VOl x IOL)
2: Voltage spikes below VSS at the MCLR/VPP pin, inducing currents greater than 80 mA, may cause latch-up.
Thus, a series resistor of 50-100Ω should be used when applying a “low” level to the MCLR/VPP pin, rather
than pulling this pin directly to VSS.
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 265
PIC18C601/801
FIGURE 22-1:
PIC18C601/801 VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL)
6.0 V
5.5 V
5.0 V
PIC18C601/801
Voltage
4.5 V
4.2V
4.0 V
3.5 V
3.0 V
2.5 V
2.0 V
25 MHz
Frequency
FIGURE 22-2:
PIC18C601/801 VOLTAGE-FREQUENCY GRAPH (EXTENDED)
6.0 V
5.5 V
Voltage
5.0 V
PIC18C601/801
4.5 V
4.2V
4.0 V
3.5 V
3.0 V
2.5 V
2.0 V
4 MHz
16 MHz
25 MHz
Frequency
FMAX = (12.0 MHz/V) (VDDAPPMIN - 2.0 V) + 4 MHz where VDDAPPMIN < 3
FMAX = (7.5 MHz/V) (VDDAPPMIN - 3.0 V) + 16 MHz where VDDAPPMIN > 3
Note: VDDAPP is the minimum voltage of the PICmicro® device in the application.
DS39541A-page 266
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
22.1
DC Characteristics
PIC18LC601/801
(Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
PIC18C601/801
(Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Param
No.
D001
Symbol
VDD
Characteristic/
Device
Min
Typ
Max
Units
PIC18LC601/801
2.0
—
5.5
V
PIC18C601/801
4.2
—
5.5
V
Conditions
Supply Voltage
D001
D002
VDR
RAM Data Retention
Voltage(1)
1.5
—
—
V
D003
VPOR
VDD Start Voltage to
ensure internal
Power-on Reset signal
—
—
0.7
V
D004
SVDD
VDD Rise Rate to
ensure internal Poweron Reset signal
0.05
—
—
See section on Power-on Reset
for details
V/ms See section on Power-on Reset
for details
Legend: Rows with industrial-extended data are shaded for improved readability.
Note 1: This is the limit to which VDD can be lowered in SLEEP mode, or during a device RESET, without losing
RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tri-stated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD or VSS, and
all features that add delta current disabled (such as WDT, Timer1 Oscillator, BOR, ...).
4: For RC osc option, current through REXT is not included. The current through the resistor can be estimated
by the formula Ir = VDD/2REXT (mA) with REXT in kOhm.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 267
PIC18C601/801
22.1
DC Characteristics (Continued)
PIC18LC601/801
(Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
PIC18C601/801
(Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Param
No.
D010
Symbol
IDD
Characteristic/
Device
Min
Typ
Max
Units
—
TBD
TBD
mA
RC osc option
FOSC = 4 MHz, VDD = 2.5V
—
TBD
TBD
mA
RC osc options
FOSC = 4 MHz, VDD = 4.2V
—
TBD
TBD
µA
LP osc option
FOSC = 32 kHz, VDD = 2.5V
—
TBD
TBD
µA
LP osc option
FOSC = 32 kHz, VDD = 4.2V
—
TBD
45
mA
EC osc option,
FOSC = 25 MHz, VDD = 5.5V
—
—
45
mA
EC osc option,
FOSC = 25 MHz, VDD = 5.5V
—
—
—
—
TBD
50
mA
mA
—
—
50
mA
—
—
50
mA
—
—
50
mA
HS osc option
FOSC = 25 MHz, VDD = 5.5V
HS + PLL osc option
FOSC = 10 MHz, VDD = 5.5V
—
—
—
—
48
TBD
µA
µA
Timer1 osc option
FOSC = 32 kHz, VDD = 2.5V
FOSC = 32 kHz, VDD = 2.5V, 25°C
—
—
—
—
TBD
TBD
µA
µA
OSCB osc option
FOSC = 32 kHz, VDD = 4.2V
FOSC = 32 kHz, VDD = 4.2V, 25°C
Supply Current(2,4)
PIC18LC601/801
D010
D010A
D010A
D010C
D010C
D013
D013
D014
D014
Conditions
PIC18C601/801
PIC18LC601/801
PIC18C601/801
PIC18LC601/801
PIC18C601/801
PIC18LC601/801
PIC18C601/801
PIC18LC601/801
PIC18C601/801
HS osc options
FOSC = 6 MHz, VDD = 2.5V
FOSC = 25 MHz, VDD = 5.5V
HS + PLL osc option
FOSC = 10 MHz, VDD = 5.5V
Legend: Rows with industrial-extended data are shaded for improved readability.
Note 1: This is the limit to which VDD can be lowered in SLEEP mode, or during a device RESET, without losing
RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tri-stated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD or VSS, and
all features that add delta current disabled (such as WDT, Timer1 Oscillator, BOR, ...).
4: For RC osc option, current through REXT is not included. The current through the resistor can be estimated
by the formula Ir = VDD/2REXT (mA) with REXT in kOhm.
DS39541A-page 268
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
22.1
DC Characteristics (Continued)
PIC18LC601/801
(Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
PIC18C601/801
(Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Param
No.
Min
Typ
Max
Units
—
—
—
TBD
—
—
5
36
TBD
µA
µA
µA
VDD = 2.5V, -40°C to +85°C
VDD = 5.5V, -40°C to +85°C
VDD = 2.5V, 25°C
—
—
TBD
—
TBD
36
µA
µA
VDD = 4.2V, -40°C to +85°C
VDD = 5.5V, -40°C to +85°C
D020A
—
—
TBD
µA
VDD = 4.2V, 25°C
D021B
—
—
TBD
—
TBD
42
µA
VDD = 4.2V, -40°C to +125°C
VDD = 5.5V, -40°C to +125°C
D020
Symbol
IPD
Characteristic/
Device
Power-down Current(3)
PIC18LC601/801
D020
D022
PIC18C601/801
∆IWDT
Module Differential Current
PIC18LC801/601
Watchdog Timer
—
—
—
—
TBD
6.5
—
—
TBD
12
TBD
TBD
µA
µA
µA
µA
VDD = 2.5V
VDD = 3.0V
VDD = 5.5V
VDD = 2.5V, 25°C
PIC18C601/801
Watchdog Timer
—
—
—
—
—
—
TBD
TBD
TBD
µA
µA
µA
VDD = 5.5V, -40°C to +85°C
VDD = 5.5V, -40°C to +125°C
VDD = 4.2V, 25°C
PIC18LC801/601
Low Voltage Detect
—
—
—
—
50
TBD
µA
µA
VDD = 2.5V
VDD = 2.5V, 25°C
PIC18C601/801
Low Voltage Detect
—
—
—
—
—
—
TBD
TBD
TBD
µA
µA
µA
VDD = 4.2V, -40°C to +85°C
VDD = 4.2V, -40°C to +125°C
VDD = 4.2V, 25°C
PIC18LC801/601
Timer1 Oscillator
—
—
—
—
3
TBD
µA
µA
VDD = 2.5V
VDD = 2.5V, 25°C
PIC18C601/801
Timer1 Oscillator
—
—
—
—
—
—
TBD
TBD
TBD
µA
µA
µA
VDD = 4.2V, -40°C to +85°C
VDD = 4.2V, -40°C to +125°C
VDD = 4.2V, 25°C
D022
D022B
∆ILVD
D022B
D025
Conditions
∆IOSCB
D025
Legend: Rows with industrial-extended data are shaded for improved readability.
Note 1: This is the limit to which VDD can be lowered in SLEEP mode, or during a device RESET, without losing
RAM data.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an
impact on the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail to rail; all I/O pins tri-stated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
3: The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD or VSS, and
all features that add delta current disabled (such as WDT, Timer1 Oscillator, BOR, ...).
4: For RC osc option, current through REXT is not included. The current through the resistor can be estimated
by the formula Ir = VDD/2REXT (mA) with REXT in kOhm.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 269
PIC18C601/801
22.2
DC Characteristics:
DC CHARACTERISTICS
PIC18C801 (Industrial, Extended)
PIC18LC601/801 (Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Min
Max
Units
Conditions
Param Symbol
Characteristic/
No.
Device
Input Low Voltage
VIL
I/O ports:
D030
with TTL buffer
VSS
D030A
—
D031
with Schmitt Trigger buffer
VSS
VSS
RC3 and RC4
VSS
D032
MCLR
D032A
OSC1 (in XT, HS and LP modes)
VSS
and T1OSI
VSS
D033
OSC1(in RC mode)(1)
VIH
Input High Voltage
I/O ports:
D040
with TTL buffer
0.25VDD + 0.8V
D040A
2.0
D041
with Schmitt Trigger buffer
0.8VDD
0.7VDD
RC3 and RC4
0.8VDD
D042
MCLR
D042A
OSC1 (in HS and LP modes) and
0.7VDD
T1OSI
0.9VDD
D043
OSC1 (RC mode)(1)
VHYS
Hysteresis of Schmitt Trigger Inputs
D050
TBD
IIL
Input Leakage Current(2,3)
D060
I/O ports
—
0.15VDD
0.8
0.2 VDD
0.3VDD
0.2 VDD
0.3VDD
V
V
V
V
V
V
0.2 VDD
V
VDD
VDD
VDD
VDD
VDD
VDD
V
V
V
V
V
V
VDD
V
TBD
V
±1
µA
VDD < 4.5V
4.5V ≤ VDD ≤ 5.5V
VDD < 4.5V
4.5V ≤ VDD ≤ 5.5V
VSS ≤ VPIN ≤ VDD,
Pin at hi-impedance
Vss ≤ VPIN ≤ VDD
Vss ≤ VPIN ≤ VDD
—
±5
µA
MCLR
OSC1
—
±5
µA
IPU
Weak Pull-up Current
D070 IPURB
PORTB weak pull-up current
50
400
µA VDD = 5V, VPIN = VSS
Note 1: In RC oscillator option, the OSC1/CLKI pin is a Schmitt Trigger input. It is not recommended that the
PICmicro device be driven with an external clock while in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified
levels represent normal operating conditions. Higher leakage current may be measured at different input
voltages.
3: Negative current is defined as current sourced by the pin.
D061
D063
DS39541A-page 270
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
22.2
DC Characteristics:
PIC18C801 (Industrial, Extended)
PIC18LC601/801 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Min
Max
Units
Conditions
DC CHARACTERISTICS
Param Symbol
Characteristic/
No.
Device
VOL
Output Low Voltage
D080
I/O ports
D080A
D083
OSC2/CLKO
(RC mode)
D083A
D084
System Bus mode
D084A
D085
Control Signals
D085A
VOH
D090
Output High Voltage(3)
I/O ports
D090A
D092
OSC2/CLKO
(RC mode)
D092A
D093
System Bus mode
D093A
D094
Control Signals
D094A
VOD
—
0.6
V
—
0.6
V
—
0.6
V
—
0.6
V
—
TBD
V
—
TBD
V
—
TBD
V
—
TBD
V
VDD - 0.7
—
V
VDD - 0.7
—
V
VDD - 0.7
—
V
VDD - 0.7
—
V
TBD
—
V
TBD
—
V
TBD
—
V
TBD
—
V
IOL = 8.5 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 7.0 mA, VDD = 4.5V,
-40°C to +125°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.2 mA, VDD = 4.5V,
-40°C to +125°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.2 mA, VDD = 4.5V,
-40°C to +125°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.2 mA, VDD = 4.5V,
-40°C to +125°C
IOH = -3.0 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -2.5 mA, VDD = 4.5V,
-40°C to +125°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.0 mA, VDD = 4.5V,
-40°C to +125°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.0 mA, VDD = 4.5V,
-40°C to +125°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.0 mA, VDD = 4.5V,
-40°C to +125°C
Open-drain High Voltage
D150
—
7.5
V RA4 pin
Capacitive Loading Specs on Output Pins
D101 CIO
All I/O pins and OSC2
—
50
pF To meet the AC Timing
(in RC mode)
Specifications
D102 CB
SCL, SDA
—
400
pF In I2C mode
Note 1: In RC oscillator option, the OSC1/CLKI pin is a Schmitt Trigger input. It is not recommended that the
PICmicro device be driven with an external clock while in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified
levels represent normal operating conditions. Higher leakage current may be measured at different input
voltages.
3: Negative current is defined as current sourced by the pin.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 271
PIC18C601/801
FIGURE 22-3:
LOW-VOLTAGE DETECT CHARACTERISTICS
VDD
(LVDIF can be
cleared in software)
VLVD
(LVDIF set by hardware)
LVDIF
TABLE 22-1:
LOW VOLTAGE DETECT CHARACTERISTICS
VCC = 2.0V to 5.5V
Commercial (C): TAMB = 0°C to +70°C
Industrial (I):
TAMB = -40°C to +85°C
Param
No.
D420
Characteristic
Symbol
Min
Typ†
Max
Units
Conditions
LVV = 0001
VLVD
2.0
2.06
2.12
V
LVV = 0010
2.2
2.27
2.34
V
LVV = 0011
2.4
2.47
2.54
V
LVV = 0100
2.5
2.58
2.66
V
LVV = 0101
2.7
2.78
2.86
V
LVV = 0110
2.8
2.89
2.98
V
LVV = 0111
3.0
3.1
3.2
V
LVV = 1000
3.3
3.41
3.52
V
LVV = 1001
3.5
3.61
3.72
V
LVV = 1010
3.6
3.72
3.84
V
LVV = 1011
3.8
3.92
4.04
V
LVV = 1100
4.0
4.13
4.26
V
LVV = 1101
4.2
4.33
4.46
V
LVV = 1110
4.5
4.64
4.78
V
D421
LVD Voltage Drift Temperature
TCVOUT
—
15
50
ppm/°C
Coefficient
∆VBG/
D422
Bandgap Voltage Drift with respect to
—
—
50
µV/V
VDD Regulation
∆VDD
D423
Bandgap Reference Voltage Value
VBG
—
1.22
V
Note: Production tested at TAMB = 25°C. Specifications over temperature limits guaranteed by characterization.
LVD Voltage on VDD
Transition High to
Low
DS39541A-page 272
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
22.3
22.3.1
AC (Timing) Characteristics
TIMING PARAMETER SYMBOLOGY
The timing parameter symbols have been created
following one of the following formats:
1. TppS2ppS
2. TppS
T
F
Frequency
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
ck
CLKO
cs
CS
di
SDI
do
SDO
dt
Data-in
io
I/O port
mc
MCLR
Uppercase letters and their meanings:
S
F
Fall
H
High
I
Invalid (Hi-impedance)
L
Low
I2C only
AA
output access
BUF
Bus free
TCC:ST (I2C specifications only)
CC
HD
Hold
ST
DAT
DATA input hold
STA
START condition
 2001 Microchip Technology Inc.
(I2C specifications only)
(I2C specifications only)
3. TCC:ST
4. Ts
T
Time
osc
rd
rw
sc
ss
t0
t1
wr
OSC1
RD
RD or WR
SCK
SS
T0CKI
T1CKI
WR
P
R
V
Z
Period
Rise
Valid
Hi-impedance
High
Low
High
Low
SU
Setup
STO
STOP condition
Advance Information
DS39541A-page 273
PIC18C601/801
22.3.2
TIMING CONDITIONS
The temperature and voltages specified in Table 22-2
apply to all timing specifications, unless otherwise
noted. Figure 22-4 specifies the load conditions for the
timing specifications.
TABLE 22-2:
TEMPERATURE AND VOLTAGE SPECIFICATIONS - AC
AC CHARACTERISTICS
FIGURE 22-4:
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Operating voltage VDD range as described in DC spec Section 22.1.
LC parts operate for industrial temperatures only.
LOAD CONDITIONS FOR DEVICE TIMING SPECIFICATIONS
Load condition 1
Load condition 2
VDD/2
RL
CL
Pin
VSS
CL
Pin
RL = 464Ω
VSS
DS39541A-page 274
CL = 50 pF
for all pins except OSC2/CLKO
and including D and E outputs as ports
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
22.3.3
TIMING DIAGRAMS AND SPECIFICATIONS
FIGURE 22-5:
EXTERNAL CLOCK TIMING
Q4
Q1
Q2
Q3
Q4
Q1
OSC1
1
3
4
3
4
2
CLKOUT
TABLE 22-3:
Param No.
EXTERNAL CLOCK TIMING REQUIREMENTS
Symbol Characteristic
FOSC
1
2
3
4
Note 1:
Typ
Max
Units
DC
—
4
MHz
DC
—
25
MHz
4
—
6.25
MHz
DC
—
25
MHz
DC
—
200
kHz
Oscillator Frequency (Note 1)
DC
—
4
MHz
4
—
25
MHz
4
—
6.25
MHz
5
—
200
kHz
Tosc External CLKI Period (Note 1)
250
—
—
ns
40
—
—
ns
40
—
—
ns
160
—
—
ns
5
—
—
µs
Oscillator Period (Note 1)
250
—
—
ns
40
—
100
ns
160
—
100
ns
5
—
—
µs
TCY
Instruction Cycle Time (Note 1)
160
TCY
DC
ns
TosL, External Clock in (OSC1) High or
2.5
—
—
µs
TosH Low Time
10
—
—
ns
TosR, External Clock in (OSC1) Rise or
—
—
50
ns
TosF Fall Time
—
—
5
ns
Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are based
on characterization data for that particular oscillator type under standard operating conditions, with the device executing code. Exceeding these specified limits may result in an unstable oscillator operation and/or higher than
expected current consumption. All devices are tested to operate at "min." values with an external clock applied to the
OSC1/CLKI pin. When an external clock input is used, the "max." cycle time limit is "DC" (no clock) for all devices.
TABLE 22-4:
External CLKI Frequency
(Note 1)
PLL CLOCK TIMING SPECIFICATION (VDD = 4.2V - 5.5V)
Param
Symbol
No.
7
Min
Characteristic
Min
Max
Units
TPLL
PLL Start-up Time
(Lock Time)
—
2
ms
∆CLK
CLKOUT Stability (Jitter) using PLL
-2
+2
%
 2001 Microchip Technology Inc.
Advance Information
Conditions
DS39541A-page 275
PIC18C601/801
FIGURE 22-6:
CLKOUT AND I/O TIMING
Q1
Q4
Q2
Q3
OSC1
11
10
CLKOUT
13
14
19
12
18
16
I/O Pin
(input)
15
17
I/O Pin
(output)
new value
old value
20, 21
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-5:
Param.
No.
10
11
12
13
14
15
16
17
18
18A
CLKOUT AND I/O TIMING REQUIREMENTS
Symbol
Characteristic
Min
TosH2ckL
TosH2ckH
TckR
TckF
TckL2ioV
TioV2ckH
TckH2ioI
TosH2ioV
TosH2ioI
Typ
Max
OSC1↑ to CLKOUT↓
—
75
200
OSC1↑ to CLKOUT↑
—
75
200
CLKOUT rise time
—
35
100
CLKOUT fall time
—
35
100
CLKOUT ↓ to Port out valid
—
— 0.5TCY + 20
Port in valid before CLKOUT ↑
0.25TCY + 25 —
—
Port in hold after CLKOUT ↑
0
—
—
OSC1↑ (Q1 cycle) to Port out valid
—
50
150
OSC1↑ (Q2 cycle) PIC18C601/801
100
—
—
to Port input invalid PIC18LC601/801
200
—
—
(I/O in hold time)
19
TioV2osH Port input valid to OSC1↑
0
—
—
(I/O in setup time)
20
TioR
Port output rise
PIC18C601/801
—
10
25
time
20A
PIC18LC601/801
—
—
60
21
TioF
Port output fall time PIC18C601/801
—
10
25
21A
PIC18LC601/801
—
—
60
INT pin high or low time
TCY
—
—
22††
TINP
23††
TRBP
RB7:RB4 change INT high or low time
TCY
—
—
††These parameters are asynchronous events, not related to any internal clock edges.
Note 1: Measurements are taken in RC mode, where CLKO pin output is 4 x TOSC.
DS39541A-page 276
Advance Information
Units Conditions
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
(1)
(1)
(1)
(1)
(1)
(1)
(1)
ns
ns
ns
ns
ns
ns
ns
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-7:
PROGRAM MEMORY READ TIMING DIAGRAM
Q1
Q2
Q3
Q4
Q1
Q2
OSC1
A<19:16>
BA0
Address
AD<15:0>
Address
Address
Data from external
150
Address
163
160
162
151
161
155
166
167
168
ALE
164
169
CS1
CS2
or CSIO
171
171A
OE
165
Operating Conditions: 2.0V <VCC <5.5V, -40°C <TA <125°C, unless otherwise stated.
TABLE 22-6:
CLKOUT AND I/O TIMING REQUIREMENTS
Param
No.
Symbol
150
TadV2alL
151
Characteristics
Min
Typ
Max
Units
Address out valid to ALE↓ (address setup time)
0.25TCY-10
—
—
ns
TalL2adl
ALE↓ to address out invalid (address hold time)
5
—
—
ns
155
TalL2oeL
ALE ↓ to OE ↓
10
0.125TCY
—
ns
160
TadZ2oeL
AD high-Z to OE ↓ (bus release to OE)
0
—
—
ns
161
ToeH2adD
OE ↑ to AD driven
0.125TCY-5
—
—
ns
162
TadV2oeH
LS data valid before OE ↑ (data setup time)
20
—
—
ns
163
ToeH2adl
OE ↑ to data in invalid (data hold time)
0
—
—
ns
164
TalH2alL
ALE pulse width
—
TCY
—
ns
165
ToeL2oeH
OE pulse width
0.5TCY-5
0.5TCY
—
ns
166
TalH2alH
ALE↑ to ALE↑ (cycle time)
—
0.25TCY
—
ns
167
Tacc
Address valid to data valid
0.75TCY-25
—
—
ns
168
Toe
OE ↓ to data valid
—
0.5TCY-25
ns
169
TalL2oeH
ALE ↓ to OE ↑
0.625TCY-10
—
0.625TCY+10
ns
171
TalH2csL
Chip select active to ALE ↓
0.25TCY-20
—
—
ns
171A
TubL2oeH
AD valid to chip select active
—
—
10
ns
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 277
PIC18C601/801
FIGURE 22-8:
8-BIT PROGRAM MEMORY FETCH TIMING DIAGRAM
Q1
Q2
Q3
Q4
Q1
Q2
OSC1
A<19:8>
Address
Address
166
150
161
151
AD<7:0>
Data
Data
Address
Address
162
162A
163
BA0
170
170A
ALE
CS1
CS2
or CSIO
OE
Operating Conditions: 2.0V <VCC <5.5V, -40°C <TA <125°C, FOSC max = 25MHz, unless otherwise stated.
TABLE 22-7:
8-BIT PROGRAM MEMORY FETCH TIMING REQUIREMENTS
Param
No.
Symbol
150
TadV2alL
151
TalL2adl
161
ToeH2adD
OE ↑ to AD driven
162
TadV2oeH
162A
Min
Typ
Max
Units
Address out valid to ALE↓ (address setup time)
0.25TCY-10
—
—
ns
ALE↓ to address out invalid (address hold time)
5
—
—
ns
0.125TCY-5
—
—
ns
LS data valid before OE ↑ (data setup time)
20
—
—
ns
TadV2oeH
MS data valid before OE ↑ (data setup time)
0.25TCY+20
—
—
ns
163
ToeH2adl
OE ↑ to data in invalid (data hold time)
0
—
—
ns
166
TalH2alH
ALE↑ to ALE↑ (cycle time)
—
0.25TCY
—
ns
170
TubH2oeH
BA0 = 0 valid before OE ↑
0.25TCY-10
—
—
ns
170A
TubL2oeH
BA0 = 1 valid before OE ↑
0.5TCY-10
—
—
ns
DS39541A-page 278
Characteristics
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-9:
PROGRAM MEMORY WRITE TIMING DIAGRAM
Q1
Q2
Q3
Q4
Q1
Q2
OSC1
A<19:16>
BA0
Address
Address
166
AD<15:0>
Data
Address
Address
153
150
156
151
ALE
CS1, CS2,
or CSIO
154
WRH or
WRL
157A
157
UB or
LB
Operating Conditions: 2.0V <VCC <5.5V, -40°C <TA <125°C unless otherwise stated.
TABLE 22-8:
PROGRAM MEMORY WRITE TIMING REQUIREMENTS
Param
No.
Symbol
150
TadV2alL
151
Characteristics
Min
Typ
Max
Units
Address out valid to ALE↓ (address setup time)
0.25TCY-10
—
—
ns
TalL2adl
ALE↓ to address out invalid (address hold time)
5
—
—
ns
153
TwrH2adl
WRn ↑ to data out invalid (data hold time)
5
—
—
ns
154
TwrL
0.5TCY-5
0.5TCY
—
ns
0.5TCY-10
—
—
ns
0.25TCY
—
—
ns
0.125TCY-5
—
—
ns
WRn pulse width
156
TadV2wrH Data valid before WRn ↑ (data setup time)
157
TbsV2wrL
Byte select valid before WRn ↓ (byte select setup time)
157A
TwrH2bsI
WRn ↑ to byte select invalid (byte select hold time)
166
TalH2alH
ALE↑ to ALE↑ (cycle time)
—
0.25TCY
—
ns
36
TIVRST
Time for Internal Reference Voltage to become stable
—
20
50
µs
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 279
PIC18C601/801
FIGURE 22-10:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Time-out
Internal
Reset
Watchdog
Timer
Reset
31
34
34
I/O Pins
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-9:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET REQUIREMENTS
Param.
Symbol
No.
Characteristic
Min
Typ
Max
Units
30
TmcL
MCLR Pulse Width (low)
2
—
—
µs
31
TWDT
Watchdog Timer Time-out Period
(No Prescaler)
7
18
33
ms
32
TOST
Oscillation Start-up Timer Period
—
—
1024TOSC
—
33
TPWRT
Power up Timer Period
28
72
132
ms
34
TIOZ
I/O Hi-Impedance from MCLR Low
or Watchdog Timer Reset
—
2
—
µs
DS39541A-page 280
Advance Information
Conditions
TOSC = OSC1 period
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-11:
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
T0CKI
41
40
42
T1OSO/T1CKI
46
45
47
48
TMR0 or
TMR1
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-10: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
Symbol
No.
40
Tt0H
41
Tt0L
42
Tt0P
Characteristic
T0CKI High Pulse Width No Prescaler
With Prescaler
T0CKI Low Pulse Width No Prescaler
With Prescaler
T0CKI Period
No Prescaler
With Prescaler
45
Tt1H
T1CKI
High
Time
46
Tt1L
T1CKI
Low
Time
47
Tt1P
T1CKI
input
period
48
Synchronous, no prescaler
Synchronous, PIC18C601/801
with prescaler PIC18LC601/801
Asynchronous PIC18C601/801
PIC18LC601/801
Synchronous, no prescaler
Synchronous, PIC18C601/801
with prescaler PIC18LC601/801
Asynchronous PIC18C601/801
PIC18LC601/801
Synchronous
Asynchronous
Ft1
T1CKI oscillator input frequency range
Tcke2tmrI Delay from external T1CKI clock edge to
timer increment
 2001 Microchip Technology Inc.
Min
Max
Units
0.5TCY + 20
10
0.5TCY + 20
10
TCY + 10
Greater of:
20 nS or TCY + 40
N
0.5TCY + 20
10
25
30
50
0.5TCY + 5
10
25
30
TBD
Greater of:
20 nS or TCY + 40
N
60
DC
2TOSC
—
—
—
—
—
—
ns
ns
ns
ns
ns
ns
—
—
—
—
—
—
—
—
—
TBD
—
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
—
50
7TOSC
ns
kHz
—
Advance Information
Conditions
N = prescale value
(1, 2, 4,..., 256)
N = prescale value
(1, 2, 4, 8)
DS39541A-page 281
PIC18C601/801
FIGURE 22-12:
CAPTURE/COMPARE/PWM TIMINGS (CCP1 AND CCP2)
CCPx
(Capture mode)
50
51
52
CCPx
(Compare or PWM mode)
53
54
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-11: CAPTURE/COMPARE/PWM REQUIREMENTS (CCP1 AND CCP2)
Param.
Symbol
No.
Characteristic
Min
Max
Units
0.5TCY + 20
10
20
0.5TCY + 20
10
20
3TCY + 40
N
—
—
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
ns
ns
ns
25
45
25
45
ns
ns
ns
ns
50
TccL
CCPx input low No Prescaler
time
With
PIC18C601/801
Prescaler PIC18LC601/801
51
TccH
CCPx input high No Prescaler
time
With
PIC18C601/801
Prescaler PIC18LC601/801
52
TccP
CCPx input period
53
TccR
CCPx output fall time
54
TccF
CCPx output fall time
DS39541A-page 282
PIC18C601/801
PIC18LC601/801
PIC18C601/801
PIC18LC601/801
Advance Information
Conditions
N = prescale
value (1, 4 or 16)
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-13:
EXAMPLE SPI MASTER MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
71
72
78
79
79
78
SCK
(CKP = 1)
80
Bit6 - - - - - -1
MSb
SDO
LSb
75, 76
SDI
MSb In
Bit6 - - - -1
LSb In
74
73
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-12: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 0)
Param.
No.
Symbol
Characteristic
Min
Max Units
70
TssL2scH,
TssL2scL
SS↓ to SCK↓ or SCK↑ input
71
TscH
SCK input high time
(Slave mode)
TscL
SCK input low time
(Slave mode)
Single Byte
40
—
ns
73
TdiV2scH,
TdiV2scL
Setup time of SDI data input to SCK edge
100
—
ns
73A
TB2B
Last clock edge of Byte1 to the 1st clock edge of
Byte2
1.5TCY + 40
—
ns
74
TscH2diL,
TscL2diL
Hold time of SDI data input to SCK edge
100
—
ns
75
TdoR
SDO data output rise time
PIC18C601/801
—
25
ns
PIC18LC601/801
—
45
ns
71A
72
72A
TCY
—
ns
1.25TCY + 30
—
ns
Single Byte
40
—
ns
Continuous
1.25TCY + 30
—
ns
Continuous
76
TdoF
SDO data output fall time
78
TscR
SCK output rise time
(Master mode)
—
25
ns
PIC18C601/801
—
25
ns
79
TscF
SCK output fall time (Master mode)
PIC18LC601/801
—
45
ns
—
25
ns
80
TscH2doV,
TscL2doV
SDO data output valid after
SCK edge
PIC18C601/801
PIC18LC601/801
—
50
ns
—
100
ns
Conditions
(Note 1)
(Note 1)
(Note 2)
Note 1: Requires the use of parameter # 73A.
2: Only if parameter #s 71A and 72A are used.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 283
PIC18C601/801
FIGURE 22-14:
EXAMPLE SPI MASTER MODE TIMING (CKE = 1)
SS
81
SCK
(CKP = 0)
71
72
79
73
SCK
(CKP = 1)
80
78
MSb
SDO
Bit6 - - - - - -1
LSb
Bit6 - - - -1
LSb In
75, 76
SDI
MSb In
74
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-13: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 1)
Param.
No.
71
71A
72
72A
73
73A
74
Symbol
TscH
TscL
TdiV2scH,
TdiV2scL
TB2B
75
TscH2diL,
TscL2diL
TdoR
76
78
TdoF
TscR
Characteristic
Min
Continuous
Single Byte
SCK input low time
Continuous
(Slave mode)
Single Byte
Setup time of SDI data input to SCK edge
1.25TCY + 30
40
1.25TCY + 30
40
100
—
—
—
—
—
ns
ns
ns
ns
ns
Last clock edge of Byte1 to the 1st clock edge
of Byte2
Hold time of SDI data input to SCK edge
1.5TCY + 40
—
ns
100
—
ns
—
—
—
—
—
—
—
—
TCY
25
45
25
25
45
25
50
100
—
ns
ns
ns
ns
ns
ns
ns
ns
ns
SCK input high time
(Slave mode)
SDO data output rise time
PIC18C601/801
PIC18LC601/801
SDO data output fall time
SCK output rise time
(Master mode)
PIC18C601/801
PIC18LC601/801
79
TscF
SCK output fall time (Master mode)
80
TscH2doV, SDO data output valid after PIC18C601/801
TscL2doV SCK edge
PIC18LC601/801
81
TdoV2scH, SDO data output setup to SCK edge
TdoV2scL
Note 1: Requires the use of parameter # 73A.
2: Only if parameter #s 71A and 72A are used.
DS39541A-page 284
Max Units
Advance Information
Conditions
(Note 1)
(Note 1)
(Note 2)
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-15:
EXAMPLE SPI SLAVE MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
83
71
72
78
79
79
78
SCK
(CKP = 1)
80
MSb
SDO
Bit6 - - - - - -1
LSb
77
75, 76
SDI
MSb In
Bit6 - - - -1
LSb In
74
73
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-14: EXAMPLE SPI MODE REQUIREMENTS (SLAVE MODE TIMING (CKE = 0))
Param
No.
Symbol
Characteristic
70
TssL2scH, SS↓ to SCK↓ or SCK↑ input
TssL2scL
71
TscH
SCK input high time
(Slave mode)
TscL
SCK input low time
(Slave mode)
71A
72
72A
Min
Continuous
Max Units
TCY
—
ns
1.25TCY + 30
—
ns
Single Byte
40
—
ns
Continuous
1.25TCY + 30
—
ns
40
—
ns
100
—
ns
Single Byte
73
TdiV2scH, Setup time of SDI data input to SCK edge
TdiV2scL
73A
TB2B
Last clock edge of Byte1 to the 1st clock edge of Byte2 1.5TCY + 40
—
ns
74
TscH2diL,
TscL2diL
Hold time of SDI data input to SCK edge
100
—
ns
75
TdoR
SDO data output rise time
—
25
ns
45
ns
76
TdoF
SDO data output fall time
—
25
ns
10
50
ns
—
25
ns
45
ns
—
25
ns
PIC18C601/801
PIC18LC601/801
77
TssH2doZ
SS↑ to SDO output hi-impedance
78
TscR
SCK output rise time
(Master mode)
79
TscF
SCK output fall time (Master mode)
80
TscH2doV, SDO data output valid after SCK PIC18C601/801
TscL2doV edge
PIC18LC601/801
83
PIC18C601/801
PIC18LC601/801
TscH2ssH, SS ↑ after SCK edge
TscL2ssH
—
1.5TCY + 40
50
ns
100
ns
—
ns
Conditions
(Note 1)
(Note 1)
(Note 2)
Note 1: Requires the use of parameter # 73A.
2: Only if parameter #s 71A and 72A are used.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 285
PIC18C601/801
FIGURE 22-16:
EXAMPLE SPI SLAVE MODE TIMING (CKE = 1)
82
SS
SCK
(CKP = 0)
70
83
71
72
SCK
(CKP = 1)
80
MSb
SDO
Bit6 - - - - - -1
LSb
75, 76
SDI
MSb In
77
Bit6 - - - -1
LSb In
74
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-15: EXAMPLE SPI SLAVE MODE REQUIREMENTS (CKE = 1)
Param
No.
70
71
71A
72
72A
73A
74
Symbol
Characteristic
Min
TssL2scH, SS↓ to SCK↓ or SCK↑ input
TssL2scL
TscH
SCK input high time
(Slave mode)
TscL
75
TB2B
TscH2diL,
TscL2diL
TdoR
76
77
78
TdoF
TssH2doZ
TscR
Continuous
Single Byte
SCK input low time
Continuous
(Slave mode)
Single Byte
Last clock edge of Byte1 to the 1st clock edge of Byte2
Hold time of SDI data input to SCK edge
SDO data output rise time
SDO data output fall time
SS↑ to SDO output hi-impedance
SCK output rise time
(Master mode)
PIC18C601/801
PIC18LC601/801
PIC18C601/801
PIC18LC601/801
79
80
TscF
SCK output fall time (Master mode)
TscH2doV, SDO data output valid after SCK
PIC18C601/801
TscL2doV edge
PIC18LC601/801
82
TssL2doV SDO data output valid after SS↓
PIC18C601/801
edge
PIC18LC601/901
83
TscH2ssH, SS ↑ after SCK edge
TscL2ssH
Note 1: Requires the use of parameter # 73A.
2: Only if parameter #s 71A and 72A are used.
DS39541A-page 286
Advance Information
Max Units Conditions
TCY
—
ns
1.25TCY + 30
40
1.25TCY + 30
40
1.5TCY + 40
100
—
—
—
—
—
—
ns
ns
ns
ns
ns
ns
—
—
—
10
—
—
—
—
—
—
—
25
45
25
50
25
45
25
50
100
50
100
—
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
1.5TCY + 40
(Note 1)
(Note 1)
(Note 2)
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-17:
I2C BUS START/STOP BITS TIMING
SCL
91
93
90
92
SDA
STOP
Condition
START
Condition
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-16: I2C BUS START/STOP BITS REQUIREMENTS (SLAVE MODE)
Param.
Symbol
No.
90
91
92
93
Characteristic
TSU:STA
START condition
Setup time
THD:STA START condition
Hold time
TSU:STO STOP condition
Setup time
THD:STO STOP condition
Hold time
FIGURE 22-18:
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
Min
Max
Units
Conditions
4700
600
4000
600
4700
600
4000
600
—
—
—
—
—
—
—
—
ns
Only relevant for Repeated
START condition
ns
After this period, the first
clock pulse is generated
ns
ns
I2C BUS DATA TIMING
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
Note: Refer to Figure 22-4 for load conditions.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 287
PIC18C601/801
TABLE 22-17: I2C BUS DATA REQUIREMENTS (SLAVE MODE)
Param
No.
100
Symbol
THIGH
Characteristic
Clock high time
Min
Max
Units
Conditions
100 kHz mode
4.0
—
µs
PIC18C601/801 must operate
at a minimum of 1.5 MHz
400 kHz mode
0.6
—
µs
PIC18C601/801 must operate
at a minimum of 10 MHz
1.5TCY
—
100 kHz mode
4.7
—
µs
PIC18C601/801 must operate
at a minimum of 1.5 MHz
400 kHz mode
1.3
—
µs
PIC18C601/801 must operate
at a minimum of 10 MHz
SSP Module
101
TLOW
Clock low time
1.5TCY
—
ns
100 kHz mode
—
1000
ns
400 kHz mode
20 + 0.1Cb
300
ns
SSP module
102
TR
103
TF
SDA and SCL rise
time
SDA and SCL fall time 100 kHz mode
—
300
ns
20 + 0.1Cb
300
ns
Cb is specified to be from
10 to 400 pF
100 kHz mode
4.7
—
µs
400 kHz mode
0.6
—
µs
Only relevant for Repeated
START condition
START condition hold 100 kHz mode
time
400 kHz mode
4.0
—
µs
0.6
—
µs
400 kHz mode
TSU:STA
90
91
THD:STA
THD:DAT
106
TSU:DAT
107
TSU:STO
92
109
TAA
110
TBUF
Cb is specified to be from
10 to 400 pF
START condition
setup time
Data input hold time
100 kHz mode
0
—
ns
400 kHz mode
0
0.9
µs
Data input setup time 100 kHz mode
250
—
ns
400 kHz mode
100
—
ns
STOP condition setup 100 kHz mode
time
400 kHz mode
4.7
—
µs
0.6
—
µs
Output valid from
clock
100 kHz mode
—
3500
ns
400 kHz mode
—
—
ns
Bus free time
100 kHz mode
4.7
—
µs
400 kHz mode
1.3
—
µs
—
400
pF
(Note 2)
(Note 1)
Time the bus must be free
before a new transmission can
start
D102
Cb
Note 1:
As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of
the falling edge of SCL to avoid unintended generation of START or STOP conditions.
A fast mode I2C bus device can be used in a standard mode I2C bus system, but the requirement tsu;DAT ≥ 250 ns must
then be met. This will automatically be the case if the device does not stretch the LOW period of the SCL signal. If such a
device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line.
Before the SCL line is released, TR max. + tsu;DAT = 1000 + 250 = 1250 ns (according to the standard mode I2C bus
specification).
2:
DS39541A-page 288
Bus capacitive loading
After this period the first clock
pulse is generated
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
MASTER SSP I2C BUS START/STOP BITS TIMING WAVEFORMS
FIGURE 22-19:
SCL
93
91
90
92
SDA
STOP
Condition
START
Condition
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-18: MASTER SSP I2C BUS START/STOP BITS REQUIREMENTS
Param.
Symbol
No.
90
91
TSU:STA
Characteristic
100 kHz mode
2(TOSC)(BRG + 1)
—
Setup time
400 kHz mode
THD:STA START condition
TSU:STO STOP condition
Setup time
93
Max
START condition
Hold time
92
Min
THD:STO STOP condition
Hold time
2(TOSC)(BRG + 1)
—
(1)
1 MHz mode
2(TOSC)(BRG + 1)
—
100 kHz mode
2(TOSC)(BRG + 1)
—
400 kHz mode
2(TOSC)(BRG + 1)
—
(1)
1 MHz mode
2(TOSC)(BRG + 1)
—
100 kHz mode
2(TOSC)(BRG + 1)
—
400 kHz mode
2(TOSC)(BRG + 1)
—
(1)
1 MHz mode
2(TOSC)(BRG + 1)
—
100 kHz mode
2(TOSC)(BRG + 1)
—
400 kHz mode
2(TOSC)(BRG + 1)
—
1 MHz mode(1) 2(TOSC)(BRG + 1)
—
Units
ns
ns
Conditions
Only relevant for
Repeated START
condition
After this period, the first
clock pulse is generated
ns
ns
Note 1: Maximum pin capacitance = 10 pF for all I2C pins.
FIGURE 22-20:
MASTER SSP I2C BUS DATA TIMING
103
102
100
101
SCL
90
106
91
107
92
SDA
In
109
109
110
SDA
Out
Note: Refer to Figure 22-4 for load conditions.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 289
PIC18C601/801
TABLE 22-19: MASTER SSP I2C BUS DATA REQUIREMENTS
Param
Symbol
No.
100
101
102
103
90
91
106
107
92
109
110
D102
Min
Max
Units
100 kHz mode
400 kHz mode
2(TOSC)(BRG + 1)
2(TOSC)(BRG + 1)
—
—
ms
ms
1 MHz mode(1)
100 kHz mode
400 kHz mode
2(TOSC)(BRG + 1)
2(TOSC)(BRG + 1)
2(TOSC)(BRG + 1)
—
—
—
ms
ms
ms
SDA and SCL
rise time
1 MHz mode(1)
100 kHz mode
400 kHz mode
2(TOSC)(BRG + 1)
—
20 + 0.1Cb
—
1000
300
ms
ns
ns
Cb is specified to be
from 10 to 400 pF
SDA and SCL
fall time
1 MHz mode(1)
100 kHz mode
400 kHz mode
—
—
20 + 0.1Cb
300
300
300
ns
ns
ns
Cb is specified to be
from 10 to 400 pF
TSU:STA
1 MHz mode(1)
START condition 100 kHz mode
setup time
400 kHz mode
—
2(TOSC)(BRG + 1)
2(TOSC)(BRG + 1)
100
—
—
ns
ms
ms
THD:STA
1 MHz mode(1)
START condition 100 kHz mode
hold time
400 kHz mode
2(TOSC)(BRG + 1)
2(TOSC)(BRG + 1)
2(TOSC)(BRG + 1)
—
—
—
ms
ms
ms
THD:DAT
Data input
hold time
1 MHz mode(1)
100 kHz mode
400 kHz mode
2(TOSC)(BRG + 1)
0
0
—
—
0.9
ms
ns
ms
Data input
setup time
1 MHz mode(1)
100 kHz mode
400 kHz mode
TBD
250
100
—
—
—
ns
ns
ns
STOP condition
setup time
1 MHz mode(1)
100 kHz mode
400 kHz mode
TBD
2(TOSC)(BRG + 1)
2(TOSC)(BRG + 1)
—
—
—
ns
ms
ms
1 MHz mode(1)
Output valid from 100 kHz mode
clock
400 kHz mode
2(TOSC)(BRG + 1)
—
—
—
3500
1000
ms
ns
ns
TBUF
Bus free time
1 MHz mode(1)
100 kHz mode
400 kHz mode
—
4.7
1.3
—
—
—
ns
ms
ms
Cb
1 MHz mode(1)
Bus capacitive loading
TBD
—
—
400
ms
pF
THIGH
TLOW
TR
TF
TSU:DAT
TSU:STO
TAA
Characteristic
Clock high time
Clock low time
Conditions
Only relevant for
Repeated START
condition
After this period, the first
clock pulse is generated
(Note 2)
Time the bus must be
free before a new
transmission can start
Note 1: Maximum pin capacitance = 10 pF for all I2C pins.
2: A fast mode I2C bus device can be used in a standard mode I2C bus system, but parameter #107 ≥ 250 ns
must then be met. This will automatically be the case if the device does not stretch the LOW period of the
SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit
to the SDA line. Before the SCL line is released, parameter #102 + parameter
#107 = 1000 + 250 = 1250 ns (for 100 kHz mode).
DS39541A-page 290
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-21:
USART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
RC6/TX/CK
pin
121
121
RC7/RX/DT
pin
120
122
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-20: USART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Param
No.
Symbol
Characteristic
TckH2dtV SYNC XMIT (Master & Slave)
Clock high to data-out valid
120
121
Tckrf
Clock out rise time and fall time
(Master mode)
122
Tdtrf
Data-out rise time and fall time
FIGURE 22-22:
Min
Max
Units
—
—
—
—
—
—
40
100
20
50
20
50
ns
ns
ns
ns
ns
ns
PIC18C601/801
PIC18LC601/801
PIC18C601/801
PIC18LC601/801
PIC18C601/801
PIC18LC601/801
Conditions
USART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
RC6/TX/CK
pin
RC7/RX/DT
pin
125
126
Note: Refer to Figure 22-4 for load conditions.
TABLE 22-21: USART SYNCHRONOUS RECEIVE REQUIREMENTS
Param
No.
Symbol
125
TdtV2ckl
126
TckL2dtl
Characteristic
SYNC RCV (Master & Slave)
Data-hold before CK ↓ (DT hold time)
Data-hold after CK ↓ (DT hold time)
 2001 Microchip Technology Inc.
Min
Max
Units
10
15
—
—
ns
ns
Advance Information
Conditions
DS39541A-page 291
PIC18C601/801
TABLE 22-22: A/D CONVERTER CHARACTERISTICS: PIC18C601/801 (INDUSTRIAL, EXTENDED)
PIC18LC601/801 (INDUSTRIAL)
Param
Symbol
No.
Characteristic
Min
Typ
Max
Units
bit
bit
Conditions
VREF = VDD ≥ 3.0V
VREF = VDD < 3.0V
A01
NR
Resolution
—
—
—
—
10
TBD
A03
EIL
Integral linearity error
—
—
—
—
<±1
TBD
LSb VREF = VDD ≥ 3.0V
LSb VREF = VDD < 3.0V
A04
EDL
Differential linearity error
—
—
—
—
<±1
TBD
LSb VREF = VDD ≥ 3.0V
LSb VREF = VDD < 3.0V
A05
EFS
Full scale error
—
—
—
—
<±1
TBD
LSb VREF = VDD ≥ 3.0V
LSb VREF = VDD < 3.0V
A06
EOFF
Offset error
—
—
—
—
<±1
TBD
LSb VREF = VDD ≥ 3.0V
LSb VREF = VDD < 3.0V
A10
—
Monotonicity
A20
VREF
Reference voltage
(VREFH - VREFL)
VREFH
Reference voltage High
A20A
A21
guaranteed(3)
0
—
—
—
VSS ≤ VAIN ≤ VREF
V
3
—
—
V
AVSS
—
AVDD + 0.3 V
V
For 10-bit resolution
A22
VREFL
Reference voltage Low
AVSS - 0.3 V
—
AVDD
V
A25
VAIN
Analog input voltage
AVSS - 0.3 V
—
VREF + 0.3 V
V
A30
ZAIN
Recommended impedance of
analog voltage source
—
—
10.0
kΩ
A40
IAD
A/D conversion PIC18C601/801
current (VDD) PIC18LC601/801
—
180
—
µA
—
90
—
µA
VREF input current(2)
10
—
1000
µA
During VAIN acquisition.
Based on differential of
VHOLD to VAIN. To
charge CHOLD, see
Section 17.0.
—
—
10
µA
During A/D conversion
cycle.
A50
IREF
Average current
consumption when
A/D is on(1)
Note 1: When A/D is off, it will not consume any current other than minor leakage current. The power-down current
spec includes any such leakage from the A/D module.
VREF current is from RA2/AN2/VREF- and RA3/AN3/VREF+ pins or AVDD and AVSS pins, whichever is
selected as reference input.
2: Vss ≤ VAIN ≤ VREF
3: The A/D conversion result either increases or remains constant as the analog input increases.
DS39541A-page 292
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
FIGURE 22-23:
A/D CONVERSION TIMING
BSF ADCON0, GO
(Note 2)
131
Q4
130
A/D CLK
132
9
A/D DATA
8
7
...
...
2
1
0
NEW_DATA
OLD_DATA
ADRES
TCY
ADIF
GO
DONE
SAMPLING STOPPED
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts.This allows the
SLEEP instruction to be executed.
2: This is a minimal RC delay (typically 100 ns), which also disconnects the holding capacitor from the analog input.
TABLE 22-23: A/D CONVERSION REQUIREMENTS
Param
Symbol
No.
130
TAD
Characteristic
A/D clock period
PIC18C601/801
Min
Max
Units
1.6
20(5)
µs
(5)
PIC18LC601/801
3.0
PIC18C601/801
2.0
20
6.0
PIC18LC601/801
Conditions
TOSC based, VREF ≥ 3.0V
µs
TOSC based, VREF full range
µs
A/D RC mode
A/D RC mode
3.0
9.0
µs
131
TCNV
Conversion time
(not including acquisition time)(1)
11
12
TAD
132
TACQ
Acquisition time(3)
15
10
—
—
µs
µs
-40°C ≤ Temp ≤ 125°C
0°C ≤ Temp ≤ 125°C
135
TSWC
Switching time from convert → sample
—
(Note 4)
1
—
µs
This may be used if the “new”
input voltage has not
changed by more than 1 LSb
(i.e., 5 mV @ 5.12V) from the
last sampled voltage (as
stated on CHOLD).
136
TAMP
Amplifier settling
time(2)
Note 1: ADRES register may be read on the following TCY cycle.
2: See Section 17.0 for minimum conditions, when input voltage has changed more than 1 LSb.
3: The time for the holding capacitor to acquire the “New” input voltage, when the voltage changes full scale
after the conversion (AVDD to AVSS, or AVSS to AVDD). The source impedance (RS) on the input channels is
50Ω.
4: On the next Q4 cycle of the device clock.
5: The time of the A/D clock period is dependent on the device frequency and the TAD clock divider.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 293
PIC18C601/801
NOTES:
DS39541A-page 294
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
23.0
DC AND AC
CHARACTERISTICS GRAPHS
AND TABLES
Graphs and Tables are not available at this time.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 295
PIC18C601/801
NOTES:
DS39541A-page 296
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
24.0
PACKAGING INFORMATION
24.1
Package Marking Information
64-Lead TQFP
Example
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
68-Lead PLCC
PIC18C601-I/PT
0017017
Example
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
XXXXXXXXXXXX
XXXXXXXXXXXX
YYWWNNN
Note:
*
0017017
Example
80-Lead TQFP
Legend:
PIC18C601-I/L
XX...X
YY
WW
NNN
PIC18C801-I/PT
0017017
Customer specific information*
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line thus limiting the number of available characters
for customer specific information.
Standard OTP marking consists of Microchip part number, year code, week code, facility code, mask
rev#, and assembly code. For OTP marking beyond this, certain price adders apply. Please check with
your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 297
PIC18C601/801
Package Marking Information (Cont’d)
84-Lead PLCC
Example
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
DS39541A-page 298
PIC18C801-I/L
0017017
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
64-Lead Plastic Thin Quad Flatpack (PT) 10x10x1 mm Body, 1.0/0.10 mm Lead Form (TQFP)
E
E1
#leads=n1
p
D1
D
2
1
B
n
CH x 45 °
α
A
c
φ
L
β
A2
A1
(F)
Units
Dimension Limits
n
p
Number of Pins
Pitch
Pins per Side
Overall Height
Molded Package Thickness
Standoff §
Foot Length
Footprint (Reference)
Foot Angle
Overall Width
Overall Length
Molded Package Width
Molded Package Length
Lead Thickness
Lead Width
Pin 1 Corner Chamfer
Mold Draft Angle Top
Mold Draft Angle Bottom
n1
A
A2
A1
L
(F)
φ
E
D
E1
D1
c
B
CH
α
β
MIN
.039
.037
.002
.018
0
.463
.463
.390
.390
.005
.007
.025
5
5
INCHES
NOM
64
.020
16
.043
.039
.006
.024
.039
3.5
.472
.472
.394
.394
.007
.009
.035
10
10
MAX
.047
.041
.010
.030
7
.482
.482
.398
.398
.009
.011
.045
15
15
MILLIMETERS*
NOM
64
0.50
16
1.00
1.10
0.95
1.00
0.05
0.15
0.45
0.60
1.00
0
3.5
11.75
12.00
11.75
12.00
9.90
10.00
9.90
10.00
0.13
0.18
0.17
0.22
0.64
0.89
5
10
5
10
MIN
MAX
1.20
1.05
0.25
0.75
7
12.25
12.25
10.10
10.10
0.23
0.27
1.14
15
15
* Controlling Parameter
§ Significant Characteristic
Notes:
Dimensions D1 and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MS-026
Drawing No. C04-085
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 299
PIC18C601/801
68-Lead Plastic Leaded Chip Carrier (L) – Square (PLCC)
E
E1
#leads=n1
D1 D
CH2 x 45 °
n 12
CH1 x 45 °
α
A3
A2
32°
A
c
B1
β
p
B
A1
D2
E2
Units
Dimension Limits
n
p
MIN
INCHES*
NOM
68
.050
17
.173
.153
.028
.029
.045
.005
.990
.990
.954
.954
.920
.920
.011
.029
.020
5
5
MAX
MILLIMETERS
NOM
68
1.27
17
4.19
4.39
3.68
3.87
0.51
0.71
0.61
0.74
1.02
1.14
0.00
0.13
25.02
25.15
25.02
25.15
24.13
24.23
24.13
24.23
22.61
23.37
22.61
23.37
0.20
0.27
0.66
0.74
0.33
0.51
0
5
0
5
MIN
Number of Pins
Pitch
Pins per Side
n1
Overall Height
A
.165
.180
Molded Package Thickness
A2
.145
.160
Standoff §
A1
.020
.035
Side 1 Chamfer Height
A3
.024
.034
Corner Chamfer 1
CH1
.040
.050
Corner Chamfer (others)
CH2
.000
.010
Overall Width
E
.985
.995
Overall Length
D
.985
.995
Molded Package Width
E1
.950
.958
Molded Package Length
D1
.950
.958
Footprint Width
E2
.890
.930
Footprint Length
D2
.890
.930
c
Lead Thickness
.008
.013
Upper Lead Width
B1
.026
.032
Lower Lead Width
B
.013
.021
α
Mold Draft Angle Top
0
10
β
Mold Draft Angle Bottom
0
10
* Controlling Parameter
§ Significant Characteristic
Notes:
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MO-047
Drawing No. C04-049
DS39541A-page 300
Advance Information
MAX
4.57
4.06
0.89
0.86
1.27
0.25
25.27
25.27
24.33
24.33
23.62
23.62
0.33
0.81
0.53
10
10
 2001 Microchip Technology Inc.
PIC18C601/801
80-Lead Plastic Thin Quad Flatpack (PT) 12x12x1 mm Body, 1.0/0.10 mm Lead Form (TQFP)
E
E1
#leads=n1
p
D1
D
2
1
B
n
CH x 45 °
A
α
c
φ
β
L
A2
A1
(F)
Units
Dimension Limits
n
p
Number of Pins
Pitch
Pins per Side
Overall Height
Molded Package Thickness
Standoff §
Foot Length
Footprint (Reference)
Foot Angle
Overall Width
Overall Length
Molded Package Width
Molded Package Length
Lead Thickness
Lead Width
Pin 1 Corner Chamfer
Mold Draft Angle Top
Mold Draft Angle Bottom
n1
A
A2
A1
L
(F)
φ
MIN
.039
.037
.002
.018
E
D
E1
D1
c
B
CH
α
β
0
.541
.541
.463
.463
.004
.007
.025
5
5
INCHES
NOM
80
.020
20
.043
.039
.004
.024
.039
3.5
.551
.551
.472
.472
.006
.009
.035
10
10
MAX
.047
.041
.006
.030
7
.561
.561
.482
.482
.008
.011
.045
15
15
MILLIMETERS*
NOM
80
0.50
20
1.00
1.10
0.95
1.00
0.05
0.10
0.45
0.60
1.00
0
3.5
13.75
14.00
13.75
14.00
11.75
12.00
11.75
12.00
0.09
0.15
0.17
0.22
0.64
0.89
5
10
5
10
MIN
MAX
1.20
1.05
0.15
0.75
7
14.25
14.25
12.25
12.25
0.20
0.27
1.14
15
15
* Controlling Parameter
§ Significant Characteristic
Notes:
Dimensions D1 and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MS-026
Drawing No. C04-092
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 301
PIC18C601/801
84-Lead Plastic Leaded Chip Carrier (L) – Square (PLCC)
E
E1
#leads=n1
D1 D
n 12
CH2 x 45°
CH1 x 45 °
α
A3
A2
32°
A
c
B1
B
β
p
A1
D2
E2
Units
Dimension Limits
n
p
INCHES*
NOM
68
.050
17
.165
.173
.145
.153
.020
.028
.024
.029
.040
.045
.000
.005
.985
.990
.985
.990
.950
.954
.950
.954
.890
.920
.890
.920
.008
.011
.026
.029
.013
.020
0
5
0
5
MIN
MAX
MILLIMETERS
NOM
68
1.27
17
4.19
4.39
3.68
3.87
0.51
0.71
0.61
0.74
1.02
1.14
0.00
0.13
25.02
25.15
25.02
25.15
24.13
24.23
24.13
24.23
22.61
23.37
22.61
23.37
0.20
0.27
0.66
0.74
0.33
0.51
0
5
0
5
MIN
Number of Pins
Pitch
Pins per Side
n1
Overall Height
A
.180
Molded Package Thickness
A2
.160
Standoff §
A1
.035
Side 1 Chamfer Height
A3
.034
Corner Chamfer 1
CH1
.050
Corner Chamfer (others)
CH2
.010
Overall Width
E
.995
Overall Length
D
.995
Molded Package Width
E1
.958
Molded Package Length
D1
.958
Footprint Width
E2
.930
Footprint Length
D2
.930
c
Lead Thickness
.013
Upper Lead Width
B1
.032
Lower Lead Width
B
.021
α
Mold Draft Angle Top
10
β
Mold Draft Angle Bottom
10
* Controlling Parameter
§ Significant Characteristic
Notes:
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed
.010” (0.254mm) per side.
JEDEC Equivalent: MO-047
Drawing No. C04-093
DS39541A-page 302
Advance Information
MAX
4.57
4.06
0.89
0.86
1.27
0.25
25.27
25.27
24.33
24.33
23.62
23.62
0.33
0.81
0.53
10
10
 2001 Microchip Technology Inc.
PIC18C601/801
APPENDIX A:
DATA SHEET
REVISION HISTORY
Revision A
APPENDIX B:
DEVICE
DIFFERENCES
The differences between the PIC18C601/801 devices
listed in this data sheet are shown in Table B-1.
This is a new data sheet.
TABLE B-1:
DEVICE DIFFERENCES
Feature
PIC18C601
PIC18C801
Maximum External
Program Memory
(Bytes)
256K
2M
Data Memory (Bytes)
1.5K
1.5K
A/D Channels
Package
Types
 2001 Microchip Technology Inc.
Advance Information
8
12
TQFP
64-pin
80-pin
PLCC
68-pin
84-pin
DS39541A-page 303
PIC18C601/801
APPENDIX C:
DEVICE MIGRATIONS
This section is intended to describe the functional and
electrical specification differences when migrating
between functionally similar devices (such as from a
PIC16C74A to a PIC16C74B).
Not Applicable
APPENDIX D:
MIGRATING FROM
OTHER PICmicro
DEVICES
This discusses some of the issues in migrating from
other PICmicro devices to the PIC18CXXX family of
devices.
D.1
PIC16CXXX to PIC18CXXX
See application note AN716.
D.2
PIC17CXXX to PIC18CXXX
See application note AN726.
DS39541A-page 304
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
APPENDIX E:
DEVELOPMENT
TOOL VERSION
REQUIREMENTS
This lists the minimum requirements (software/
firmware) of the specified development tool to support
the devices listed in this data sheet.
MPLAB® IDE:
TBD
MPLAB®
SIMULATOR:
TBD
MPLAB®
ICE 3000:
PIC18C601/801 Processor Module:
Part Number TBD
PIC18C601/801 Device Adapter:
Socket
Part Number
64-pin TQFP
TBD
68-pin PLCC
TBD
80-pin TQFP
TBD
84-pin PLCC
TBD
MPLAB® ICD:
®
PRO MATE II:
TBD
TBD
®
PICSTART Plus:
TBD
TM
Assembler:
TBD
MPASM
MPLAB® C18 C Compiler: TBD
Note:
Please read all associated README.TXT
files that are supplied with the development tools. These "read me" files will discuss product support and any known
limitations.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 305
PIC18C601/801
NOTES:
DS39541A-page 306
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
INDEX
A
A/D ................................................................................... 193
A/D Converter Flag (ADIF Bit) ................................. 195
A/D Converter Interrupt, Configuring ....................... 197
ADCON0 Register .......................................... 193, 195
ADCON1 Register .......................................... 193, 194
ADCON2 Register ................................................... 193
ADRES Register ............................................. 193, 195
Analog Port Pins, Configuring ................................. 199
Associated Registers ............................................... 201
Block Diagram ......................................................... 196
Block Diagram, Analog Input Model ........................ 197
Configuring the Module ........................................... 197
Conversion Clock (TAD) ........................................... 199
Conversion Status (GO/DONE Bit) .......................... 195
Conversions ............................................................. 200
Converter Characteristics ............................... 272, 292
Effects of a RESET .................................................. 206
Equations
Acquisition Time .............................................. 198
Minimum Charging Time ................................. 198
Operation During SLEEP ......................................... 206
Sampling Requirements .......................................... 198
Sampling Time ......................................................... 198
Special Event Trigger (CCP) .......................... 144, 200
Timing Diagram ....................................................... 293
Absolute Maximum Ratings ............................................. 265
Access Bank ...................................................................... 58
ADCON0 Register ........................................................... 193
GO/DONE Bit .......................................................... 195
Registers
ADCON2 (A/D Control 2) ................................. 195
ADCON1 Register .................................................. 193, 194
ADCON2 Register ........................................................... 193
ADDLW ............................................................................ 221
ADDWF ............................................................................ 221
ADDWFC ......................................................................... 222
ADRES Register ..................................................... 193, 195
AKS .................................................................................. 167
Analog-to-Digital Converter. See A/D
ANDLW ............................................................................ 222
ANDWF ............................................................................ 223
Assembler
MPASM Assembler ................................................. 259
B
Bank Select Register ......................................................... 58
Baud Rate Generator ....................................................... 164
Associated Registers ............................................... 179
BC .................................................................................... 223
BCF .................................................................................. 224
BF .................................................................................... 167
Block Diagram ................................................................. 119
Block Diagrams
A/D ........................................................................... 196
Baud Rate Generator .............................................. 164
Capture Mode Operation ......................................... 143
Compare Mode Operation ....................................... 144
Interrupt Logic ............................................................ 90
Low Voltage Detect ................................................. 203
MSSP
I2C Mode ......................................................... 159
SPI Mode ......................................................... 153
On-Chip Reset Circuit, Simplified .............................. 29
 2001 Microchip Technology Inc.
Phase Lock Loop ...................................................... 23
PORTA
RA3:RA0 and RA5 Pins .................................. 103
RA4/T0CKI Pin ................................................ 104
PORTB
RB3 Pin ........................................................... 106
RB3:RB0 Port Pins .......................................... 106
RB7:RB4 Port Pins .......................................... 105
PORTC .................................................................... 108
PORTD
I/O Mode ......................................................... 110
System Bus Mode ........................................... 111
PORTD (In I/O Port Mode) ...................................... 124
PORTE
I/O Mode ......................................................... 113
System Bus Mode ........................................... 114
PORTF
RF2:RF0 Pins .................................................. 116
RF5:RF3 Pins .................................................. 117
RF7:RF6 Pins .................................................. 117
PORTG
I/O Mode ......................................................... 119
System Bus Mode ........................................... 120
PORTH
RH3:RH0 Pins (I/O Mode) ............................... 121
RH3:RH0 Pins (System Bus Mode) ................ 122
RH7:RH4 Pins ................................................. 121
PORTJ
I/O Mode ......................................................... 124
System Bus Mode ........................................... 125
Simplified PWM Diagram ........................................ 146
SSP (SPI Mode) ...................................................... 153
Timer0
16-bit Mode ..................................................... 128
8-bit Mode ....................................................... 128
Timer1 ..................................................................... 131
16-bit R/W Mode ............................................. 132
Timer2 ..................................................................... 136
Timer3 ..................................................................... 138
16-bit R/W Mode ............................................. 138
USART
Asynchronous Receive ................................... 185
Asynchronous Transmit .................................. 183
Watchdog Timer ...................................................... 211
BN ................................................................................... 224
BNC ................................................................................. 225
BNN ................................................................................. 225
BNOV .............................................................................. 226
BNZ ................................................................................. 226
BOV ................................................................................. 229
BRA ................................................................................. 227
BRG ................................................................................. 164
BSF ................................................................................. 227
BSR. See Bank Select Register.
BTFSC ............................................................................. 228
BTFSS ............................................................................. 228
BTG ................................................................................. 229
Bus .................................................................................. 176
Bus Collision During a RESTART Condition ................... 175
Bus Collision During a START Condition ........................ 173
Bus Collision During a STOP Condition .......................... 176
BZ .................................................................................... 230
Advance Information
DS39541A-page 307
PIC18C601/801
C
D
CALL ................................................................................ 230
Capture (CCP Module) .................................................... 142
Block Diagram ......................................................... 143
CCP Pin Configuration ............................................. 142
CCPR1H:CCPR1L Registers ................................... 142
Changing Between Capture Prescalers ................... 143
Software Interrupt .................................................... 143
Timer1 Mode Selection ............................................ 142
Capture/Compare/PWM (CCP) ....................................... 141
Capture Mode. See Capture
CCP1 ....................................................................... 142
CCPR1H Register ........................................... 142
CCPR1L Register ............................................ 142
CCP2 ....................................................................... 142
CCPR2H Register ........................................... 142
CCPR2L Register ............................................ 142
Compare Mode. See Compare
Interaction of Two CCP Modules ............................. 142
PWM Mode. See PWM
Registers Associated with Capture
and Compare ........................................... 145
Timer Resources ..................................................... 142
Timing Diagram ....................................................... 282
Chip Select
Chip Select 2 (CS2) ................................................... 71
Chip Select I/O (CSIO) ...................................................... 71
Chip Selects
Chip Select 1 (CS1) ................................................... 71
Clocking Scheme ............................................................... 46
CLRF ............................................................................... 231
CLRWDT ......................................................................... 231
Code Examples ............................................................... 154
Changing Between Capture Prescalers ................... 143
Clearing RAM Using Indirect Addressing .................. 59
Combination Unlock (Macro) ..................................... 51
Combination Unlock (Subroutine) .............................. 50
Fast Register Stack ................................................... 45
Initializing PORTA .................................................... 103
Initializing PORTB .................................................... 105
Initializing PORTC ................................................... 108
Initializing PORTD ................................................... 110
Initializing PORTE .................................................... 113
Initializing PORTF .................................................... 116
Initializing PORTG ................................................... 119
Initializing PORTH ................................................... 121
Initializing PORTJ .................................................... 124
Programming Chip Select Signals ........................... 116
Saving STATUS, WREG and BSR Registers .......... 101
Table Read ................................................................ 75
Table Write ................................................................ 77
COMF .............................................................................. 232
Compare (CCP Module) .................................................. 144
Block Diagram ......................................................... 144
CCP Pin Configuration ............................................. 144
CCPR1H:CCPR1L Registers ................................... 144
Software Interrupt .................................................... 144
Special Event Trigger .................... 133, 139, 144, 200
Timer1 Mode Selection ............................................ 144
Configuration Address Map, Example ............................... 71
Configuration Bits ............................................................ 207
Table ........................................................................ 207
Context Saving During Interrupts ..................................... 101
CPFSEQ .......................................................................... 232
CPFSGT .......................................................................... 233
CPFSLT ........................................................................... 233
Data Memory ..................................................................... 49
General Purpose Registers ....................................... 49
Special Function Registers ........................................ 49
Data Memory Map
Program Bit Not Set .................................................. 51
Program Bit Set ......................................................... 52
DAW ................................................................................ 234
DC and AC Characteristics Graphs and Tables .............. 295
DCFSNZ .......................................................................... 235
DECF ............................................................................... 234
DECFSZ .......................................................................... 235
Development Support ...................................................... 259
Development Tool Version Requirements ....................... 305
Device Differences .......................................................... 303
Device Migrations ............................................................ 304
Direct Addressing .............................................................. 60
DS39541A-page 308
E
Electrical Characteristics ................................................. 265
Errata ................................................................................... 7
External Wait Cycles ......................................................... 72
F
Fast Register Stack ........................................................... 45
Firmware Instructions ...................................................... 215
G
General Call Address Sequence ..................................... 162
General Call Address Support ......................................... 162
GOTO .............................................................................. 236
I
I/O Mode .......................................................................... 119
I/O Ports .......................................................................... 103
I2C (SSP Module) ............................................................ 159
ACK Pulse .......................................................159, 160
Addressing .............................................................. 160
Block Diagram ......................................................... 159
Read/Write Bit Information (R/W Bit) ....................... 160
Reception ................................................................ 160
Serial Clock (RC3/SCK/SCL) .................................. 160
Slave Mode ............................................................. 159
Timing Diagram, Data ............................................. 287
Timing Diagram, START/STOP Bits ....................... 287
Transmission ........................................................... 160
I2C Master Mode Reception ............................................ 167
I2C Master Mode RESTART Condition ........................... 166
I2C Module
Acknowledge Sequence Timing .............................. 170
Baud Rate Generator .............................................. 164
Block Diagram ................................................. 164
BRG Reset due to SDA Collision ............................ 174
BRG Timing ............................................................. 165
Bus Collision
Acknowledge ................................................... 172
RESTART Condition ....................................... 175
RESTART Condition Timing (Case1) .............. 175
RESTART Condition Timing (Case2) .............. 175
START Condition ............................................ 173
START Condition Timing ........................173, 174
STOP Condition .............................................. 176
STOP Condition Timing (Case1) ..................... 176
STOP Condition Timing (Case2) ..................... 176
Transmit Timing .............................................. 172
Bus Collision Timing ................................................ 172
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
Clock Arbitration ...................................................... 171
Clock Arbitration Timing (Master Transmit) ............. 171
General Call Address Support ................................. 162
Master Mode 7-bit Reception Timing ....................... 169
Master Mode Operation ........................................... 164
Master Mode START Condition ............................... 165
Master Mode Transmission ..................................... 167
Master Mode Transmit Sequence ........................... 164
Multi-Master Mode ................................................... 172
Repeated START Condition Timing ........................ 166
STOP Condition Receive or Transmit Timing .......... 170
STOP Condition Timing ........................................... 170
Waveforms for 7-bit Reception ................................ 161
Waveforms for 7-bit Transmission ........................... 161
ICEPIC In-Circuit Emulator .............................................. 260
INCF ................................................................................ 236
INCFSZ ............................................................................ 237
In-Circuit Serial Programming (ICSP) .............................. 207
Indirect Addressing ............................................................ 60
FSR Register ............................................................. 59
INFSNZ ............................................................................ 237
Initialization Conditions for All Registers ............................ 34
Instruction Cycle ................................................................ 46
Instruction Flow/Pipelining ................................................. 47
Instruction Format ............................................................ 217
Instruction Set .................................................................. 215
ADDLW .................................................................... 221
ADDWF ................................................................... 221
ADDWFC ................................................................. 222
ANDLW .................................................................... 222
ANDWF ................................................................... 223
BC ............................................................................ 223
BCF ......................................................................... 224
BN ............................................................................ 224
BNC ......................................................................... 225
BNN ......................................................................... 225
BNOV ...................................................................... 226
BNZ ......................................................................... 226
BOV ......................................................................... 229
BRA ......................................................................... 227
BSF .......................................................................... 227
BTFSC ..................................................................... 228
BTFSS ..................................................................... 228
BTG ......................................................................... 229
BZ ............................................................................ 230
CALL ........................................................................ 230
CLRF ....................................................................... 231
CLRWDT ................................................................. 231
COMF ...................................................................... 232
CPFSEQ .................................................................. 232
CPFSGT .................................................................. 233
CPFSLT ................................................................... 233
DAW ........................................................................ 234
DCFSNZ .................................................................. 235
DECF ....................................................................... 234
DECFSZ .................................................................. 235
GOTO ...................................................................... 236
INCF ........................................................................ 236
INCFSZ .................................................................... 237
INFSNZ .................................................................... 237
IORLW ..................................................................... 238
IORWF ..................................................................... 238
LFSR ....................................................................... 239
MOVF ...................................................................... 239
MOVFF .................................................................... 240
 2001 Microchip Technology Inc.
MOVLB .................................................................... 240
MOVLW ................................................................... 241
MOVWF .................................................................. 241
MULLW ................................................................... 242
MULWF ................................................................... 242
NEGF ...................................................................... 243
NOP ........................................................................ 243
POP ......................................................................... 244
PUSH ...................................................................... 244
RCALL ..................................................................... 245
RESET .................................................................... 245
RETFIE ................................................................... 246
RETLW .................................................................... 246
RETURN ................................................................. 247
RLCF ....................................................................... 247
RLNCF .................................................................... 248
RRCF ...................................................................... 248
RRNCF .................................................................... 249
SETF ....................................................................... 249
SLEEP ..................................................................... 250
SUBFWB .........................................................250, 251
SUBLW ................................................................... 251
SUBWF ................................................................... 252
SUBWFB ................................................................. 253
SWAPF ................................................................... 254
TBLRD .................................................................... 255
TBLWT .................................................................... 256
TSTFSZ ................................................................... 257
XORLW ................................................................... 257
XORWF ................................................................... 258
Instruction Set, Summary ................................................ 218
INT Interrupt (RB0/INT). See Interrupt Sources
INTCON Register
RBIF Bit ................................................................... 105
Inter-Integrated Circuit. See I2C
Interrupt Control Registers ................................................ 91
INTCON Register ...................................................... 91
INTCON2 Register .................................................... 92
INTCON3 Register .................................................... 93
IPR Registers ............................................................ 99
PIE Registers ............................................................ 97
PIR Registers ............................................................ 95
RCON Register ......................................................... 94
Interrupt Sources .......................................................89, 207
A/D Conversion Complete ....................................... 197
Capture Complete (CCP) ........................................ 143
Compare Complete (CCP) ...................................... 144
Interrupt-on-Change (RB7:RB4) ............................. 105
RB0/INT Pin, External ............................................. 101
SSP Receive/Transmit Complete ............................ 149
TMR0 Overflow ....................................................... 129
TMR1 Overflow ...............................................130, 133
TMR2 to PR2 Match ................................................ 136
TMR2 to PR2 Match (PWM) ...........................135, 146
TMR3 Overflow ...............................................137, 139
USART Receive/Transmit Complete ....................... 177
Interrupts, Enable Bits
CCP1 Enable (CCP1IE Bit) ..................................... 143
Interrupts, Flag Bits
A/D Converter Flag (ADIF Bit) ................................. 195
CCP1 Flag (CCP1IF Bit) ........................ 142, 143, 144
Interrupt-on-Change (RB7:RB4) Flag
(RBIF Bit) ................................................ 105
IORLW ............................................................................. 238
IORWF ............................................................................ 238
Advance Information
DS39541A-page 309
PIC18C601/801
K
P
KEELOQ Evaluation and Programming Tools ................... 262
Packaging ........................................................................ 297
Phase Lock Loop
Block Diagram ........................................................... 23
Time-out .................................................................... 30
PICDEM 1 Low Cost PICmicro
Demonstration Board .............................................. 261
PICDEM 17 Demonstration Board .................................. 262
PICDEM 2 Low Cost PIC16CXX
Demonstration Board .............................................. 261
PICDEM 3 Low Cost PIC16CXXX
Demonstration Board .............................................. 262
PICSTART Plus Entry Level
Development Programmer ...................................... 261
Pin Functions
AVDD .......................................................................... 20
AVSS .......................................................................... 20
MCLR/VPP ................................................................. 12
OSC1/CLKI ................................................................ 12
OSC2/CLKO .............................................................. 12
RA0/AN0 ................................................................... 13
RA1/AN1 ................................................................... 13
RA2/AN2/VREF- ......................................................... 13
RA3/AN3/VREF+ ........................................................ 13
RA4/T0CKI ................................................................ 13
RA5/AN4/SS/LVDIN .................................................. 13
RB0/INT0 ................................................................... 14
RB1/INT1 ................................................................... 14
RB2/INT2 ................................................................... 14
RB3/INT3 ................................................................... 14
RB4 ........................................................................... 14
RB5 ........................................................................... 14
RB6 ........................................................................... 14
RB7 ........................................................................... 14
RC0/T1OSO/T1CKI ................................................... 15
RC1/T1OSI ................................................................ 15
RC2/CCP1 ................................................................. 15
RC3/SCK/SCL ........................................................... 15
RC4/SDI/SDA ............................................................ 15
RC5/SDO .................................................................. 15
RC6/TX/CK ................................................................ 15
RC7/RX/DT ............................................................... 15
RD0/AD0 ................................................................... 16
RD0/PSP0 ................................................................. 16
RD1/AD1 ................................................................... 16
RD2/AD2 ................................................................... 16
RD3/AD3 ................................................................... 16
RD4/AD4 ................................................................... 16
RD5/AD5 ................................................................... 16
RD6/AD6 ................................................................... 16
RD7/AD7 ................................................................... 16
RE0/ALE .................................................................... 17
RE1/OE ..................................................................... 17
RE2/CS ........................................................ 17, 18, 19
RE2/WRL .................................................................. 17
RE3/WRH .................................................................. 17
RE4 ........................................................................... 17
RE5 ........................................................................... 17
RE6 ........................................................................... 17
RE7/CCP2 ................................................................. 17
RF0/AN5 .................................................................... 18
RF1/AN6 .................................................................... 18
RF2/AN7 .................................................................... 18
RF3/AN8 .................................................................... 18
RF4/AN9 .................................................................... 18
L
LFSR ................................................................................ 239
Loading the SSPBUF (SSPSR) Registers ....................... 154
Low Voltage Detect .......................................................... 203
Block Diagram ......................................................... 203
LVDCON Register ................................................... 204
LVD. See Low Voltage Detect.
M
MEMCOM. See Memory Control Register
Memory .............................................................................. 39
Memory Control Register (MEMCOM) ............................... 63
Memory Organization ........................................................ 39
Data Memory ............................................................. 49
Program Memory ....................................................... 39
Migrating from other PICmicro Devices ........................... 304
MOVF .............................................................................. 239
MOVFF ............................................................................ 240
MOVLB ............................................................................ 240
MOVLW ........................................................................... 241
MOVWF ........................................................................... 241
MPLAB C17 and MPLAB C18 C Compilers .................... 259
MPLAB ICD In-Circuit Debugger ..................................... 261
MPLAB ICE High Performance Universal
In-Circuit Emulator with MPLAB IDE ....................... 260
MPLAB Integrated Development
Environment Software ............................................. 259
MPLINK Object Linker/MPLIB Object Librarian ............... 260
MULLW ............................................................................ 242
Multi-Master Mode ........................................................... 172
Multiplication Algorithm
16 x 16 Signed ........................................................... 86
16 x 16 Unsigned ....................................................... 86
Multiply Examples
16 x 16 Signed Routine ............................................. 87
16 x 16 Unsigned Routine ......................................... 86
8 x 8 Signed Routine ................................................. 86
8 x 8 Unsigned Routine ............................................. 86
MULWF ............................................................................ 242
N
NEGF ............................................................................... 243
NOP ................................................................................. 243
O
On-Chip Reset Circuit ........................................................ 29
OPTION_REG Register ..................................................... 62
PS2:PS0 Bits ........................................................... 129
PSA Bit .................................................................... 129
T0CS Bit .................................................................. 129
T0SE Bit ................................................................... 129
OSCCON Register ............................................................. 25
Oscillator Configuration ................................................... 207
Oscillator Configurations .................................................... 21
HS .............................................................................. 21
LP .............................................................................. 21
RC ....................................................................... 21, 22
Oscillator, Timer1 ............................................130, 133, 137
Oscillator, Timer3 ............................................................. 139
Oscillator, WDT ................................................................ 210
DS39541A-page 310
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
RF5/AN10 .................................................................. 18
RF6/AN11 .................................................................. 18
RF7 ............................................................................ 18
RG0/CANTX1 ............................................................ 19
RG1/CANTX2 ............................................................ 19
RG2/CANRX .............................................................. 19
RG3 ........................................................................... 19
RG4 ........................................................................... 19
RH1/A17 .................................................................... 19
RH2/A18 .................................................................... 19
RH3/A19 .................................................................... 19
RH4/AN12 ................................................................. 19
RH5/AN13 ................................................................. 19
RH6/AN14 ................................................................. 19
RH7/AN15 ................................................................. 19
RJ0/AD8 .................................................................... 20
RJ1/AD9 .................................................................... 20
RJ2/AD10 .................................................................. 20
RJ3/AD11 .................................................................. 20
RJ4/AD12 .................................................................. 20
RJ5/AD13 .................................................................. 20
RJ6/AD14 .................................................................. 20
RJ7/AD15 .................................................................. 20
VDD ............................................................................ 20
VSS ............................................................................ 20
POP ................................................................................. 244
POR. See Power-on Reset
PORTA
Associated Registers ............................................... 104
Block Diagram
RA3:RA0 and RA5 Pins ................................... 103
RA4/T0CKI Pin ................................................ 104
Functions ................................................................. 104
Initialization .............................................................. 103
PORTA Register ...................................................... 103
TRISA Register ........................................................ 103
PORTB
Associated Registers ............................................... 107
Block Diagram
RB3 Pin ........................................................... 106
RB3:RB0 Port Pins .......................................... 106
RB7:RB4 Port Pins .......................................... 105
Functions ................................................................. 107
Initialization .............................................................. 105
PORTB Register ...................................................... 105
RB0/INT Pin, External ............................................. 101
RB7:RB4 Interrupt-on-Change Flag (RBIF Bit) ....... 105
TRISB Register ........................................................ 105
PORTC
Associated Registers ............................................... 109
Block Diagram ......................................................... 108
Functions ................................................................. 109
Initialization .............................................................. 108
PORTC Register ...................................................... 108
RC3/SCK/SCL Pin ................................................... 160
RC7/RX/DT Pin ....................................................... 179
TRISC Register .............................................. 108, 177
PORTD
Associated Registers ............................................... 112
Block Diagram
I/O Mode .......................................................... 110
System Bus Mode ........................................... 111
Functions ................................................................. 112
Initialization .............................................................. 110
PORTD Register ...................................................... 110
TRISD Register ....................................................... 110
 2001 Microchip Technology Inc.
PORTE
Associated Registers .............................................. 115
Block Diagram
I/O Mode ......................................................... 113
System Bus Mode ........................................... 114
Functions ................................................................. 115
Initialization ............................................................. 113
PORTE Register ..................................................... 113
TRISE Register ....................................................... 113
PORTF
Associated Registers .............................................. 118
Block Diagram
RF2:RF0 Pins .................................................. 116
RF5:RF3 Pins .................................................. 117
RF7:RF6 Pins .................................................. 117
Functions ................................................................. 118
Initialization ............................................................. 116
PORTF Register ...................................................... 116
TRISF ...................................................................... 116
PORTG ............................................................................ 119
Associated Registers .............................................. 120
Block Diagram
System Bus Mode ........................................... 120
Functions ................................................................. 120
Initialization ............................................................. 119
PORTG Register ..................................................... 119
TRISG ..................................................................... 119
PORTH
Associated Registers .............................................. 123
Block Diagram .................................................121, 122
Functions ................................................................. 123
Initialization ............................................................. 121
PORTH Register ..................................................... 121
TRISH ..................................................................... 121
PORTJ
Associated Registers .............................................. 126
Block Diagram
I/O Mode ......................................................... 124
System Bus Mode ........................................... 125
Functions ................................................................. 126
Initialization ............................................................. 124
PORTJ Register ...................................................... 124
TRISJ ...................................................................... 124
Postscaler, WDT
Assignment (PSA Bit) .............................................. 129
Rate Select (PS2:PS0 Bits) ..................................... 129
Switching Between Timer0 and WDT ..................... 129
Power-down Mode. See SLEEP
Power-on Reset (POR) .............................................30, 207
Oscillator Start-up Timer (OST) ........................30, 207
Power-up Timer (PWRT) ...................................30, 207
Time-out Sequence ................................................... 30
Time-out Sequence on Power-up .......................32, 33
Timing Diagram ....................................................... 280
Prescaler, Capture .......................................................... 143
Prescaler, Timer0 ............................................................ 129
Assignment (PSA Bit) .............................................. 129
Rate Select (PS2:PS0 Bits) ..................................... 129
Switching Between Timer0 and WDT ..................... 129
Prescaler, Timer1 ............................................................ 131
Prescaler, Timer2 ............................................................ 146
PRO MATE II Universal Device Programmer .................. 261
Product Identification System .......................................... 317
Advance Information
DS39541A-page 311
PIC18C601/801
Program Counter
PCL Register ............................................................. 46
PCLATH Register ...................................................... 46
Program Memory ............................................................... 39
Boot Loader ............................................................... 43
Memory Map, PIC18C601
Program Bit Not Set ........................................... 40
Program Bit Set ................................................. 41
Memory Map, PIC18C801
Program Bit Not Set ........................................... 40
Program Bit Set ................................................. 42
Program Memory Map
PIC18C601 ................................................................ 40
Program Bit Set ................................................. 41
PIC18C801 ................................................................ 40
Program Bit Set ................................................. 42
Programming, Device Instructions ................................... 215
PUSH ............................................................................... 244
PWM (CCP Module) ........................................................ 146
Block Diagram ......................................................... 146
CCPR1H:CCPR1L Registers ................................... 146
Duty Cycle ............................................................... 146
Example Frequencies/Resolutions .......................... 147
Output Diagram ....................................................... 146
Period ...................................................................... 146
Registers Associated with PWM .............................. 147
Setup for PWM Operation ........................................ 147
TMR2 to PR2 Match ....................................... 135, 146
Q
Q Clock ............................................................................ 146
R
RAM. See Data Memory
RCALL ............................................................................. 245
RCSTA Register
SPEN Bit .................................................................. 177
Reader Response ............................................................ 316
Register File ....................................................................... 49
Register File Summary ...................................................... 54
Registers
ADCON0 (A/D Control 0) .......................................... 193
ADCON1 (A/D Control 1) ......................................... 194
CCP1CON and CCP2CON (CCP Control) .............. 141
CONFIG1H (Configuration Register 1 High) ............ 208
CONFIG2H (Configuration Register 2 High) ............ 209
CONFIG2L (Configuration Register 2 Low) ............. 208
CONFIG4L (Configuration Register 4 Low) ............. 209
CSEL2 (Chip Select 2) ............................................... 70
CSELIO (Chip Select I/O) .......................................... 70
INTCON (Interrupt Control) ........................................ 91
INTCON2 (Interrupt Control 2) ................................... 92
INTCON3 (Interrupt Control 3) ................................... 93
IPR (Interrupt Priority) ................................................ 99
LVDCON (LVD Control) ........................................... 204
MEMCON (Memory Control) ..................................... 63
OSCCON (Oscillator Control) .................................... 25
PIE (Peripheral Interrupt Enable) ............................... 97
PIR (Peripheral Interrupt Request) ............................ 95
PSPCON (PSP Control) ............................................ 50
RCON (Register Control) ........................................... 94
RCON (RESET Control) ..................................... 31, 62
DS39541A-page 312
RCSTA (Receive Status and Control) ..................... 178
SSPCON1 (SSP Control 1) ..................................... 151
SSPCON2 (SSP Control 2) ...................................... 152
SSPSTAT (SSP Status) .......................................... 150
STATUS .................................................................... 61
STKPTR (Stack Pointer) ........................................... 44
T0CON (Timer0 Control) ......................................... 127
T1CON (Timer1 Control) ......................................... 130
T2CON (Timer2 Control) ......................................... 135
T3CON (Timer3 Control) ......................................... 137
TXSTA (Transmit Status and Control) ..................... 177
WDTCON (Watchdog Timer Control) ...................... 210
RESET ............................................................. 29, 207, 245
Timing Diagram ....................................................... 280
RETFIE ............................................................................ 246
RETLW ............................................................................ 246
RETURN ......................................................................... 247
Revision History .............................................................. 303
RH3:RH0 Pins (I/O Mode) ............................................... 121
RH3:RH0 Pins (System Bus Mode) ................................ 122
RH7:RH4 Pins ................................................................. 121
RLCF ............................................................................... 247
RLNCF ............................................................................ 248
RRCF .............................................................................. 248
RRNCF ............................................................................ 249
S
Sales and Support ........................................................... 317
SCI. See USART
SCK ................................................................................. 153
SDI .................................................................................. 153
SDO ................................................................................. 153
Serial Clock, SCK ............................................................ 153
Serial Communication Interface. See USART
Serial Data In, SDI ........................................................... 153
Serial Data Out, SDO ...................................................... 153
Serial Peripheral Interface. See SPI
SETF ............................................................................... 249
Slave Select Synchronization .......................................... 156
Slave Select, SS .............................................................. 153
SLEEP ............................................................ 207, 212, 250
Software Simulator (MPLAB SIM) ................................... 260
Special Event Trigger. See Compare
Special Features of the CPU ........................................... 207
Special Function Register Map ......................................... 53
Special Function Registers ................................................ 49
SPI
Associated Registers ............................................... 158
Master Mode ........................................................... 155
Serial Clock ............................................................. 153
Serial Data In ........................................................... 153
Serial Data Out ........................................................ 153
Slave Select ............................................................ 153
SPI Clock ................................................................. 155
SPI Mode ................................................................. 153
SPI Module
Slave Mode ............................................................. 156
Slave Select Synchronization .................................. 156
Slave Synch Timing ................................................. 156
Slave Timing with CKE = 0 ...................................... 157
Slave Timing with CKE = 1 ...................................... 157
SS .................................................................................... 153
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
SSP .................................................................................. 149
Block Diagram
SPI Mode ......................................................... 153
Block Diagram (SPI Mode) ...................................... 153
I2C Mode. See I2C
SPI Mode ................................................................. 153
SPI Mode. See SPI
SSPBUF .................................................................. 155
SSPCON1 ............................................................... 151
SSPCON2 ............................................................... 152
SSPSR .................................................................... 155
SSPSTAT ................................................................ 150
TMR2 Output for Clock Shift ........................... 135, 136
SSP Module
SPI Master Mode ..................................................... 155
SPI Slave Mode ....................................................... 156
SSPCON1 Register ......................................................... 151
SSPCON2 Register ......................................................... 152
SSPOV ............................................................................ 167
SSPSTAT Register .......................................................... 150
R/W Bit .................................................................... 160
SUBFWB ................................................................ 250, 251
SUBLW ............................................................................ 251
SUBWF ............................................................................ 252
SUBWFB ......................................................................... 253
SWAPF ............................................................................ 254
Synchronous Serial Port. See SSP
T
Table Pointer Register ....................................................... 74
Table Read ........................................................................ 75
Table Read/Write Control Registers .................................. 74
Table Write ........................................................................ 77
16-bit External
16-bit Word Write Mode ..................................... 81
Byte Select Mode .............................................. 82
Byte Write Mode ................................................ 80
8-bit External ............................................................. 78
Table Writes
Long Writes ............................................................... 83
TBLRD ............................................................................. 255
TBLWT ............................................................................. 256
Timer0 .............................................................................. 127
Associated Registers ............................................... 129
Block Diagram
16-bit Mode ...................................................... 128
8-bit Mode ........................................................ 128
Clock Source Edge Select (T0SE Bit) ..................... 129
Clock Source Select (T0CS Bit) .............................. 129
Interrupt ................................................................... 101
Overflow Interrupt .................................................... 129
Prescaler. See Prescaler, Timer0
T0CON Register ...................................................... 127
Timing Diagram ....................................................... 281
Timer1 .............................................................................. 130
Associated Registers ............................................... 134
Block Diagram ......................................................... 131
16-bit R/W Mode .............................................. 132
Oscillator ......................................................... 130, 133
Overflow Interrupt ........................................... 130, 133
 2001 Microchip Technology Inc.
Prescaler. See Prescaler, Timer1
Special Event Trigger (CCP) ...........................133, 144
T1CON Register ...................................................... 130
Timing Diagram ....................................................... 281
TMR1H Register ..................................................... 130
TMR1L Register ...................................................... 130
TMR3L Register ...................................................... 137
Timer2
Associated Registers .............................................. 136
Block Diagram ......................................................... 136
Postscaler. See Postscaler, Timer2
PR2 Register ...................................................135, 146
Prescaler. See Prescaler, Timer2
SSP Clock Shift ...............................................135, 136
T2CON Register ...................................................... 135
TMR2 Register ........................................................ 135
TMR2 to PR2 Match Interrupt ................ 135, 136, 146
Timer3 ............................................................................. 137
Associated Registers .............................................. 139
Block Diagram ......................................................... 138
16-bit R/W Mode ............................................. 138
Oscillator .........................................................137, 139
Overflow Interrupt ............................................137, 139
Special Event Trigger (CCP) ................................... 139
T3CON Register ...................................................... 137
TMR3H Register ..................................................... 137
Timing Diagrams
Acknowledge Sequence Timing .............................. 170
Baud Rate Generator with Clock Arbitration ........... 165
BRG Reset Due to SDA Collision ........................... 174
Bus Collision
START Condition Timing ................................ 173
Bus Collision During a RESTART Condition
(Case 1) .................................................. 175
Bus Collision During a RESTART Condition
(Case 2) .................................................. 175
Bus Collision During a START Condition
(SCL = 0) ................................................. 174
Bus Collision During a STOP Condition .................. 176
Bus Collision for Transmit and Acknowledge .......... 172
I2C Bus Data ........................................................... 289
I2C Master Mode First START Bit Timing ............... 165
I2C Master Mode Reception Timing ........................ 169
I2C Master Mode Transmission Timing ................... 168
Master Mode Transmit Clock Arbitration ................. 171
Repeated START Condition .................................... 166
Slave Synchronization ............................................. 156
Slow Rise Time ......................................................... 33
SPI Mode Timing (Master Mode) SPI Mode
Master Mode Timing Diagram ......................... 155
SPI Mode Timing (Slave Mode with CKE = 0) ........ 157
SPI Mode Timing (Slave Mode with CKE = 1) ........ 157
STOP Condition Receive or Transmit ..................... 170
Time-out Sequence on Power-up ............................. 32
USART Asynchronous Master Transmission .......... 184
USART Asynchronous Reception ........................... 186
USART Synchronous Reception ............................. 189
USART Synchronous Transmission ........................ 188
Wake-up from SLEEP via Interrupt ......................... 213
Advance Information
DS39541A-page 313
PIC18C601/801
Timing Diagrams and Specifications ............................... 275
A/D Conversion ........................................................ 293
Capture/Compare/PWM (CCP) ............................... 282
CLKOUT and I/O ..................................................... 276
External Clock .......................................................... 275
I2C Bus Data ............................................................ 287
I2C Bus START/STOP Bits ...................................... 287
Oscillator Start-up Timer (OST) ............................... 280
Power-up Timer (PWRT) ......................................... 280
RESET ..................................................................... 280
Timer0 and Timer1 .................................................. 281
USART Synchronous Receive
(Master/Slave) ......................................... 291
USART Synchronous Transmission
(Master/Slave) ......................................... 291
Watchdog Timer (WDT) ........................................... 280
TRISE Register ................................................................ 113
TSTFSZ ........................................................................... 257
Two-Word Instructions ....................................................... 48
TXSTA Register ............................................................... 177
BRGH Bit ................................................................. 179
W
Wake-up from SLEEP .............................................207, 212
Timing Diagram ....................................................... 213
Watchdog Timer (WDT) ..........................................207, 210
Associated Registers ............................................... 211
Block Diagram ......................................................... 211
Postscaler. See Postscaler, WDT
Programming Considerations .................................. 210
RC Oscillator ........................................................... 210
Time-out Period ....................................................... 210
Timing Diagram ....................................................... 280
WDTCON Register .................................................. 210
Waveform for General Call Address Sequence .............. 162
WCOL ............................................................. 165, 167, 170
WCOL Status Flag .......................................................... 165
Worldwide Sales and Service .......................................... 318
WWW, On-Line Support ..............................................7, 315
X
XORLW ........................................................................... 257
XORWF ........................................................................... 258
U
Universal Synchronous Asynchronous
Receiver Transmitter. See USART
USART ............................................................................. 177
Asynchronous Mode ................................................ 183
Master Transmission ....................................... 184
Receive Block Diagram ................................... 185
Reception ........................................................ 186
Registers Associated with Reception .............. 186
Registers Associated with Transmission ......... 184
Transmit Block Diagram .................................. 183
Baud Rate Generator (BRG) ................................... 179
Baud Rate Error, Calculating ........................... 179
Baud Rate Formula ......................................... 179
High Baud Rate Select (BRGH Bit) ................. 179
Sampling .......................................................... 179
Serial Port Enable (SPEN Bit) ................................. 177
Synchronous Master Mode ...................................... 187
Reception ........................................................ 189
Registers Associated with Reception .............. 189
Registers Associated with Transmission ......... 187
Timing Diagram,
Synchronous Receive ..................... 291
Timing Diagram,
Synchronous Transmission ............. 291
Transmission ................................................... 188
Synchronous Slave Mode ........................................ 190
Registers Associated with Reception .............. 191
Registers Associated with Transmission ......... 190
DS39541A-page 314
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
ON-LINE SUPPORT
Systems Information and Upgrade Hot Line
Microchip provides on-line support on the Microchip
World Wide Web (WWW) site.
The web site is used by Microchip as a means to make
files and information easily available to customers. To
view the site, the user must have access to the Internet
and a web browser, such as Netscape or Microsoft
Explorer. Files are also available for FTP download
from our FTP site.
The Systems Information and Upgrade Line provides
system users a listing of the latest versions of all of
Microchip’s development systems software products.
Plus, this line provides information on how customers
can receive any currently available upgrade kits.The
Hot Line Numbers are:
1-800-755-2345 for U.S. and most of Canada, and
1-480-792-7302 for the rest of the world.
001024
Connecting to the Microchip Internet Web Site
The Microchip web site is available by using your
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www.microchip.com
The file transfer site is available by using an FTP service to connect to:
ftp://ftp.microchip.com
The web site and file transfer site provide a variety of
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Development Tools, Data Sheets, Application Notes,
User’s Guides, Articles and Sample Programs. A variety of Microchip specific business information is also
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available for consideration is:
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• Conferences for products, Development Systems,
technical information and more
• Listing of seminars and events
 2001 Microchip Technology Inc.
Trademarks: The Microchip name, logo, PIC, PICmicro,
PICMASTER, PICSTART, PRO MATE, KEELOQ, SEEVAL,
MPLAB and The Embedded Control Solutions Company
are registered trademarks of Microchip Technology
Incorporated in the U.S.A. and other countries.
Total Endurance, ICSP, In-Circuit Serial Programming,
FilterLab, MXDEV, microID, FlexROM, fuzzyLAB, MPASM,
MPLINK, MPLIB, PICDEM, ICEPIC and Migratable
Memory are trademarks and SQTP is a service mark of
Microchip in the U.S.A.
All other trademarks mentioned herein are the property of
their respective companies.
Advance Information
DS39541A-page 315
PIC18C601/801
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation
can better serve you, please FAX your comments to the Technical Publications Manager at (480) 792-4150.
Please list the following information, and use this outline to provide us with your comments about this Data Sheet.
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Literature Number: DS39541A
Questions:
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3. Do you find the organization of this data sheet easy to follow? If not, why?
4. What additions to the data sheet do you think would enhance the structure and subject?
5. What deletions from the data sheet could be made without affecting the overall usefulness?
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8. How would you improve our software, systems, and silicon products?
DS39541A-page 316
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
Device
X
Temperature
Range
/XX
XXX
Package
Pattern
Examples:
a)
b)
Device
PIC18C601/801(1), PIC18C601/801T(2):
VDD range, 4.2V to 5.5V
PIC18LC601/801(1), PIC18LC601/801T(2)
VDD range, 2.5V to 5.5V
Temperature Range
I
E
=
=
-40°C to +70°C (Industrial)
-40°C to +125°C (Extended)
Package
PT
L
=
=
TQFP
PLCC
Pattern
QTP, SQTP, ROM Code (factory specified) or
Special Requirements. Blank for OTP and
Windowed devices.
PIC18LC601 - I/L = Industrial temp., PLCC
package, Extended VDD limits, 16-bit data bus.
PIC18LC801 - E/PT = Extended temp., TQFP
package, Extended VDD limits, 16-bit data bus.
Note 1: C =
LC =
2: T =
Standard Voltage Range
Wide Voltage Range
In tape and reel (both PLCC and
TQFP packages)
SALES AND SUPPORT
Data Sheets
Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following:
1.
2.
3.
Your local Microchip sales office
The Microchip Corporate Literature Center U.S. FAX: (480) 792-7277
The Microchip Worldwide Site (www.microchip.com)
Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using.
New Customer Notification System
Register on our web site (www.microchip.com/cn) to receive the most current information on our products.
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 317
PIC18C601/801
NOTES:
DS39541A-page 318
Advance Information
 2001 Microchip Technology Inc.
PIC18C601/801
NOTES:
 2001 Microchip Technology Inc.
Advance Information
DS39541A-page 319
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
Corporate Office
China - Beijing
Singapore
2355 West Chandler Blvd.
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Tel: 480-792-7200 Fax: 480-792-7277
Technical Support: 480-792-7627
Web Address: http://www.microchip.com
Microchip Technology Beijing Office
Unit 915
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Tel: 86-10-85282100 Fax: 86-10-85282104
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Tel: 65-334-8870 Fax: 65-334-8850
China - Shanghai
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Tel: 886-2-2717-7175 Fax: 886-2-2545-0139
Rocky Mountain
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Tel: 480-792-7966 Fax: 480-792-7456
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ASIA/PACIFIC (continued)
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10/01/00
Microchip received QS-9000 quality system
certification for its worldwide headquarters,
design and wafer fabrication facilities in
Chandler and Tempe, Arizona in July 1999. The
Company’s quality system processes and
procedures are QS-9000 compliant for its
PICmicro® 8-bit MCUs, KEELOQ® code hopping
devices, Serial EEPROMs and microperipheral
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All rights reserved. © 2001 Microchip Technology Incorporated. Printed in the USA. 1/01
Printed on recycled paper.
Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by
updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is
assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual
property rights arising from such use or otherwise. Use of Microchip’s products as critical components in life support systems is not authorized except with
express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, except as maybe explicitly expressed herein, under any intellectual property rights. The Microchip logo and name are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. All rights
reserved. All other trademarks mentioned herein are the property of their respective companies.
DS39541A-page 320
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 2001 Microchip Technology Inc.