MICROCHIP PIC12CE519

12CF5XX_GEBook Page 1 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
8-Pin, 8-Bit CMOS Microcontroller with
EEPROM Data Memory
Devices:
Pin Diagram:
High-Performance RISC CPU:
• Only 33 single word instructions to learn
• All instructions are single cycle (1 µs) except for
program branches which are two-cycle
• Operating speed: DC - 4 MHz clock input
DC - 1 µs instruction cycle
•
•
•
•
•
EPROM
Program
RAM
Data
EEPROM
Data
PIC12CE518
512 x 12
25 x 8
16 x 8
PIC12CE519
1024 x 12
41 x 8
16 x 8
12-bit wide instructions
8-bit wide data path
Special function hardware registers
Two-level deep hardware stack
Direct, indirect and relative addressing modes for
data and instructions
Peripheral Features:
• 8-bit real-time clock/counter (TMR0) with 8-bit
programmable prescaler
• 1,000,000 erase/write cycle EEPROM data
memory
• EEPROM data retention > 40 years
VDD
1
GP5/OSC1/CLKIN
2
GP4/OSC2
GP3/MCLR/VPP
3
4
VSS
8
7
6
5
GP0
GP1
GP2/T0CKI
Special Microcontroller Features:
Memory
Device
PDIP, SOIC, Windowed CERDIP
PIC12CE518
PIC12CE519
PIC12CE518 and PIC12CE519 are 8-bit microcontrollers packaged in 8-lead packages. They are based on
the Enhanced PIC16C5X family.
• In-Circuit Serial Programming (ICSP™) of program memory (via two pins)
• Internal 4 MHz RC oscillator with programmable
calibration
• Power-on Reset (POR)
• Device Reset Timer (DRT)
• Watchdog Timer (WDT) with its own on-chip RC
oscillator for reliable operation
• Programmable code-protection
• Power saving SLEEP mode
• Wake-up from SLEEP on pin change
• Internal weak pull-ups on I/O pins
• Internal pull-up on MCLR pin
• Selectable oscillator options:
- INTRC: Internal 4 MHz RC oscillator
- EXTRC: External low-cost RC oscillator
- XT:
Standard crystal/resonator
- LP:
Power saving, low frequency crystal
CMOS Technology:
• Low-power, high-speed CMOS EPROM/
EEPROM technology
• Fully static design
• Wide temperature range:
- Commercial: 0°C to +70°C
- Industrial: -40°C to +85°C
- Extended: -40°C to +125°C
• Wide operating voltage range:
-Commercial: 3.0V to 5.5V
-Industrial: 3.0V to 5.5V
-Extended: 4.5V to 5.5V
• Low power consumption
- < 2 mA typical @ 5V, 4 MHz
- 15 µA typical @ 3V, 32 kHz
- < 1 µA typical standby current
 1997 Microchip Technology Inc.
Preliminary
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PIC12CE5XX
TABLE OF CONTENTS
1.0
General Description..................................................................................................................................................................... 3
2.0
PIC12CE5XX Device Varieties.................................................................................................................................................... 5
3.0
Architectural Overview ................................................................................................................................................................ 7
4.0
Memory Organization ................................................................................................................................................................ 11
5.0
PIC12CE518I/O Port ................................................................................................................................................................. 19
6.0
EEPROM Peripheral Operation................................................................................................................................................. 21
7.0
Timer0 Module and TMR0 Register .......................................................................................................................................... 25
8.0
Special Features of the CPU..................................................................................................................................................... 29
9.0
Instruction Set Summary ........................................................................................................................................................... 41
10.0 Development Support................................................................................................................................................................ 53
11.0 Electrical Characteristics - PIC12CE5XX .................................................................................................................................. 57
12.0 DC and AC Characteristics - PIC12CE5XX .............................................................................................................................. 69
13.0 Packaging Information............................................................................................................................................................... 73
14.0 Appendix A ................................................................................................................................................................................ 77
Index .................................................................................................................................................................................................... 83
PIC12CE5XX Product Identification System........................................................................................................................................ 87
To Our Valued Customers
We constantly strive to improve the quality of all our products and documentation. We have spent an exceptional
amount of time to ensure that these documents are correct. However, we realize that we may have missed a few
things. If you find any information that is missing or appears in error, please use the reader response form in the
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DS40172A-page 2
Preliminary
 1997 Microchip Technology Inc.
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PIC12CE5XX
1.0
GENERAL DESCRIPTION
1.1
The 8-pin PIC12CE5XX from Microchip Technology is
a family of low-cost, high performance, 8-bit, fully static,
EPROM/EEPROM-based CMOS microcontrollers. It
employs a RISC architecture with only 33 single word/
single cycle instructions. All instructions are single
cycle (1 µs) except for program branches which take
two cycles. The PIC12CE5XX delivers performance an
order of magnitude higher than its competitors in the
same price category. The 12-bit wide instructions are
highly symmetrical resulting in 2:1 code compression
over other 8-bit microcontrollers in its class. The easy
to use and easy to remember instruction set reduces
development time significantly.
The PIC12CE5XX products are equipped with special
features that reduce system cost and power requirements. The Power-On Reset (POR) and Device Reset
Timer (DRT) eliminate the need for external reset circuitry. There are four oscillator configurations to choose
from, including INTRC internal oscillator mode and the
power-saving LP (Low Power) oscillator. Power saving
SLEEP mode, Watchdog Timer and code protection
features improve system cost, power and reliability.
Applications
The PIC12CE5XX series fits perfectly in applications
ranging from sensory systems, gas detectors and
security systems to low-power remote transmitters/
receivers. The EPROM programming technology
makes customizing application programs (transmitter
codes, appliance settings, receiver frequencies, etc.)
extremely fast and convenient. While the EEPROM
data memory technology allows for the changing of calibrations factors and security codes, the small footprint
8-pin packages, for through hole or surface mounting,
make this microcontroller series perfect for applications
with space limitations. Low-cost, low-power, high performance, ease of use and I/O flexibility make the
PIC12CE5XX series very versatile even in areas where
no microcontroller use has been considered before
(e.g., timer functions, replacement of “glue” logic and
PLD’s in larger systems, coprocessor applications).
The PIC12CE5XX are available in the cost-effective
One-Time-Programmable (OTP) versions which are
suitable for production in any volume. The customer
can take full advantage of Microchip’s price leadership
in OTP microcontrollers while benefiting from the OTP’s
flexibility.
The PIC12CE5XX products are supported by a full-featured macro assembler, a software simulator, an in-circuit emulator, a ‘C’ compiler, fuzzy logic support tools,
a low-cost development programmer, and a full featured programmer. All the tools are supported on IBM
PC and compatible machines.
 1997 Microchip Technology Inc.
Preliminary
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PIC12CE5XX
TABLE 1-1:
PIC12CXXX FAMILY OF DEVICES
PIC12C508(A) PIC12C509(A) PIC12CE518 PIC12CE519
Clock
Memory
Features
PIC12C672
4
4
4
10
10
EPROM Program
Memory
512 x 12
1024 x 12
512 x 12
1024 x 12
1024 x 14
2048 x 14
RAM Data Memory
(bytes)
25
41
25
41
128
128
16
16
EEPROM Data Memory (bytes)
Peripherals
PIC12C671
Maximum Frequency 4
of Operation (MHz)
TMR0
TMR0
TMR0
TMR0
TMR0
A/D Converter (8-bit) —
Channels
Timer Module(s)
TMR0
—
—
—
4
4
Wake-up from
SLEEP on
pin change
Yes
Yes
Yes
Yes
Yes
Yes
Interrupt Sources
—
—
4
4
I/O Pins
5
5
5
5
5
5
Input Pins
1
1
1
1
1
1
Internal Pull-ups
Yes
Yes
Yes
Yes
Yes
Yes
In-Circuit Serial Pro- Yes
gramming
Yes
Yes
Yes
Yes
Yes
Number of Instruc- 33
tions
33
33
33
35
35
Packages
8-pin DIP,
JW, SOIC
8-pin DIP,
JW, SOIC
8-pin DIP,
JW, SOIC
8-pin DIP,
JW, SOIC
8-pin DIP,
JW, SOIC
8-pin DIP,
JW, SOIC
All PIC12CE5XX devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capability.
All PIC12CE5XX devices use serial programming with data pin GP0 and clock pin GP1.
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Preliminary
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PIC12CE5XX
2.0
PIC12CE5XX DEVICE
VARIETIES
2.3
A variety of packaging options are available.
Depending
on
application
and
production
requirements, the proper device option can be
selected using the information in this section. When
placing orders, please use the PIC12CE5XX Product
Identification System at the back of this data sheet to
specify the correct part number.
2.1
UV Erasable Devices
The UV erasable version, offered in windowed cerdip
package, is optimal for prototype development and
pilot programs.
The UV erasable version can be erased and
reprogrammed to any of the configuration modes.
Note:
Please note that erasing the device will
also erase the pre-programmed internal
calibration value for the internal oscillator.
The calibration value must be saved prior
to erasing the part.
Microchip's PICSTART PLUS and PRO MATE programmers all support programming of the
PIC12CE5XX. Third party programmers also are available; refer to the Microchip Third Party Guide for a list
of sources.
2.2
Quick-Turnaround-Production (QTP)
Devices
Microchip offers a QTP Programming Service for
factory production orders. This service is made
available for users who choose not to program a
medium to high quantity of units and whose code
patterns have stabilized. The devices are identical to
the OTP devices but with all EPROM locations and fuse
options already programmed by the factory. Certain
code and prototype verification procedures do apply
before production shipments are available. Please contact your local Microchip Technology sales office for
more details.
2.4
Serialized Quick-Turnaround
Production (SQTPSM) Devices
Microchip offers a unique programming service where
a few user-defined locations in each device are
programmed with different serial numbers. The serial
numbers may be random, pseudo-random or
sequential.
Serial programming allows each device to have a
unique number which can serve as an entry-code,
password or ID number.
One-Time-Programmable (OTP)
Devices
The availability of OTP devices is especially useful for
customers who need the flexibility for frequent code
updates or small volume applications.
The OTP devices, packaged in plastic packages permit
the user to program them once. In addition to the
program memory, the configuration bits must also be
programmed.
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Preliminary
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PIC12CE5XX
NOTES:
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PIC12CE5XX
3.0
ARCHITECTURAL OVERVIEW
The high performance of the PIC12CE5XX family can
be attributed to a number of architectural features
commonly found in RISC microprocessors. To begin
with, the PIC12CE5XX uses a Harvard architecture in
which program and data are accessed on separate
buses. This improves bandwidth over traditional von
Neumann architecture where program and data are
fetched on the same bus. Separating program and
data memory further allows instructions to be sized
differently than the 8-bit wide data word. Instruction
opcodes are 12-bits wide making it possible to have all
single word instructions. A 12-bit wide program
memory access bus fetches a 12-bit instruction in a
single cycle. A two-stage pipeline overlaps fetch and
execution of instructions. Consequently, all instructions
(33) execute in a single cycle (1µs @ 4MHz) except for
program branches.
The PIC12CE518 addresses 512 x 12 of program
memory, the PIC12CE519 addresses 1K x 12 of
program memory. All program memory is internal.
The PIC12CE5XX can directly or indirectly address its
register files and data memory. All special function
registers including the program counter are mapped in
the data memory. The PIC12CE5XX has a highly
orthogonal (symmetrical) instruction set that makes it
possible to carry out any operation on any register
using any addressing mode. This symmetrical nature
and lack of ‘special optimal situations’ make
programming with the PIC12CE5XX simple yet
efficient. In addition, the learning curve is reduced
significantly.
The PIC12CE5XX device contains an 8-bit ALU and
working register. The ALU is a general purpose
arithmetic unit. It performs arithmetic and Boolean
functions between data in the working register and any
register file.
The ALU is 8-bits wide and capable of addition,
subtraction, shift and logical operations. Unless
otherwise mentioned, arithmetic operations are two's
complement in nature. In two-operand instructions,
typically one operand is the W (working) register. The
other operand is either a file register or an immediate
constant. In single operand instructions, the operand
is either the W register or a file register.
The W register is an 8-bit working register used for
ALU operations. It is not an addressable register.
Depending on the instruction executed, the ALU may
affect the values of the Carry (C), Digit Carry (DC),
and Zero (Z) bits in the STATUS register. The C and
DC bits operate as a borrow and digit borrow out bit,
respectively, in subtraction. See the SUBWF and ADDWF
instructions for examples.
A simplified block diagram is shown in Figure 3-1, with
the corresponding device pins described in Table 3-1.
The PIC12CE5XX contains a 16 X 8 EEPROM
memory array for storing non-volatile information such
as calibration data or security codes. This memory
has an endurance of 1,000,000 erase/write cycles and
a retention of 40+ years.
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Preliminary
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PIC12CE5XX
PIC12CE5XX BLOCK DIAGRAM
12
8
Data Bus
Program Counter
GP0
GP1
GP2/T0CKI
GP3/MCLR/VPP
GP4/OSC2
GP5/OSC1/CLKIN
RAM
25 x 8 or
41 x 8
File
Registers
STACK1
STACK2
Program 12
Bus
RAM Addr
9
Addr MUX
Instruction reg
Direct Addr
5
5-7
Indirect
Addr
FSR reg
STATUS reg
8
3
OSC1/CLKIN
OSC2
Timing
Generation
Internal RC
OSC
16 X 8
EEPROM
Data
Memory
MUX
Device Reset
Timer
Instruction
Decode &
Control
GPIO
SDA
EPROM
512 x 12 or
1024 x 12
Program
Memory
SCL
FIGURE 3-1:
ALU
Power-on
Reset
8
Watchdog
Timer
W reg
Timer0
MCLR
VDD, VSS
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PIC12CE5XX
TABLE 3-1:
PIC12CE5XX PINOUT DESCRIPTION
DIP
Pin #
SOIC
Pin #
I/O/P
Type
GP0
7
7
I/O
TTL/ST Bi-directional I/O port/ serial programming data. Can
be software programmed for internal weak pull-up and
wake-up from SLEEP on pin change. This buffer is a
Schmitt Trigger input when used in serial programming
mode.
GP1
6
6
I/O
TTL/ST Bi-directional I/O port/ serial programming clock. Can
be software programmed for internal weak pull-up and
wake-up from SLEEP on pin change. This buffer is a
Schmitt Trigger input when used in serial programming
mode.
Name
Buffer
Type
Description
GP2/T0CKI
5
5
I/O
ST
Bi-directional I/O port. Can be configured as T0CKI.
GP3/MCLR/VPP
4
4
I
TTL
Input port/master clear (reset) input/programming voltage input. When configured as MCLR, this pin is an
active low reset to the device. Voltage on MCLR/VPP
must not exceed VDD during normal device operation.
Can be software programmed for internal weak pull-up
and wake-up from SLEEP on pin change. Weak pullup always on if configured as MCLR
GP4/OSC2
3
3
I/O
TTL
Bi-directional I/O port/oscillator crystal output. Connections to crystal or resonator in crystal oscillator
mode (XT and LP modes only, GPIO in other modes).
GP5/OSC1/CLKIN
2
2
I/O
TTL/ST Bidirectional IO port/oscillator crystal input/external
clock source input (GPIO in Internal RC mode only,
OSC1 in all other oscillator modes). TTL input when
GPIO, ST input in external RC oscillator mode.
VDD
1
1
P
—
Positive supply for logic and I/O pins
VSS
8
8
P
—
Ground reference for logic and I/O pins
Legend: I = input, O = output, I/O = input/output, P = power, — = not used, TTL = TTL input,
ST = Schmitt Trigger input
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Preliminary
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PIC12CE5XX
3.1
Clocking Scheme/Instruction Cycle
3.2
The clock input (OSC1/CLKIN pin) is internally divided
by four to generate four non-overlapping quadrature
clocks namely Q1, Q2, Q3 and Q4. Internally, the
program counter is incremented every Q1, and the
instruction is fetched from program memory and
latched into instruction register in Q4. It is decoded
and executed during the following Q1 through Q4. The
clocks and instruction execution flow is shown in
Figure 3-2 and Example 3-1.
Instruction Flow/Pipelining
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)
then two cycles are required to complete the
instruction (Example 3-1).
A fetch cycle begins with the program counter (PC)
incrementing in Q1.
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).
FIGURE 3-2:
CLOCK/INSTRUCTION CYCLE
Q1
Q2
Q3
Q4
Q2
Q1
Q3
Q4
Q1
Q2
Q3
Q4
OSC1
Q1
Q2
Internal
phase
clock
Q3
Q4
PC
PC
PC+1
Fetch INST (PC)
Execute INST (PC-1)
EXAMPLE 3-1:
PC+2
Fetch INST (PC+1)
Execute INST (PC)
Fetch INST (PC+2)
Execute INST (PC+1)
INSTRUCTION PIPELINE FLOW
1. MOVLW 03H
2. MOVWF GPIO
3. CALL
SUB_1
4. BSF
GPIO, BIT1
Fetch 1
Execute 1
Fetch 2
Execute 2
Fetch 3
Execute 3
Fetch 4
Flush
Fetch SUB_1 Execute 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.
DS40172A-page 10
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PIC12CE5XX
4.0
MEMORY ORGANIZATION
FIGURE 4-1:
PIC12CE5XX memory is organized into program memory and data memory. For devices with more than 512
bytes of program memory, a paging scheme is used.
Program memory pages are accessed using one STATUS register bit. For the PIC12CE519 with a data
memory register file of more than 32 registers, a banking scheme is used. Data memory banks are accessed
using the File Select Register (FSR).
PROGRAM MEMORY MAP
AND STACK FOR THE
PIC12CE5XX
PC<11:0>
12
CALL, RETLW
Stack Level 1
Stack Level 2
Reset Vector (note 1)
The PIC12CE5XX devices have a 12-bit Program
Counter (PC) capable of addressing a 2K x 12
program memory space.
On-chip Program
Memory
Only the first 512 x 12 (0000h-01FFh) for the
PIC12CE518 and 1K x 12 (0000h-03FFh) for the
PIC12CE519 are physically implemented. Refer to
Figure 4-1. Accessing a location above these
boundaries will cause a wrap-around within the first
512 x 12 space (PIC12CE518) or 1K x 12 space
(PIC12CE519). The effective reset vector is at 000h,
(see Figure 4-1). Location 01FFh (PIC12CE518) or
location 03FFh (PIC12CE519), the hardwired reset
vector location, contains the internal clock oscillator
calibration value. This value is set at Microchip and
should never be overwritten.
Upon reset, the
MOVLW XX is executed, the PC wraps to location
0000h, thus making 0000h the effective reset vector.
User Memory
Space
Program Memory Organization
4.1
512 Word (PIC12CE518)
0000h
01FFh
0200h
On-chip Program
Memory
1024 Word (PIC12CE519)
03FFh
0400h
7FFh
Note 1: Address 0000h becomes the
effective reset vector. Location
01FFh (PIC12CE518) or location
03FFh (PIC12CE519) contains the
MOVLW XX INTRC oscillator
calibration value.
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PIC12CE5XX
4.2
Data Memory Organization
FIGURE 4-2:
Data memory is composed of registers, or bytes of
RAM. Therefore, data memory for a device is specified
by its register file. The register file is divided into two
functional groups: special function registers and
general purpose registers.
PIC12CE518 REGISTER FILE
MAP
File Address
The special function registers include the TMR0
register, the Program Counter (PC), the Status
Register, the I/O registers (ports), and the File Select
Register (FSR). In addition, special purpose registers
are used to control the I/O port configuration and
prescaler options.
The general purpose registers are used for data and
control information under command of the instructions.
00h
INDF(1)
01h
TMR0
02h
PCL
03h
STATUS
04h
FSR
05h
OSCCAL
06h
GPIO
07h
For the PIC12CE518, the register file is composed of 7
special function registers and 25 general purpose
registers (Figure 4-2).
General
Purpose
Registers
For the PIC12CE519, the register file is composed of 7
special function registers, 25 general purpose
registers, and 16 general purpose registers that may
be addressed using a banking scheme (Figure 4-3).
4.2.1
1Fh
GENERAL PURPOSE REGISTER FILE
Note 1:
The general purpose register file is accessed either
directly or indirectly through the file select register
FSR (Section 4.8).
FIGURE 4-3:
Not a physical register. See Indirect
Data Addressing, Section 4.8.
PIC12CE519 REGISTER FILE MAP
FSR<6:5>
00
01
File Address
00h
INDF(1)
01h
TMR0
02h
PCL
03h
STATUS
04h
FSR
05h
OSCCAL
06h
GPIO
20h
Addresses map
back to
addresses
in Bank 0.
07h
General
Purpose
Registers
2Fh
0Fh
30h
10h
General
Purpose
Registers
General
Purpose
Registers
3Fh
1Fh
Bank 0
Note 1:
DS40172A-page 12
Bank 1
Not a physical register. See Indirect
Data Addressing, Section 4.8.
Preliminary
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PIC12CE5XX
4.2.2
The special registers can be classified into two sets.
The special function registers associated with the
“core” functions are described in this section. Those
related to the operation of the peripheral features are
described in the section for each peripheral feature.
SPECIAL FUNCTION REGISTERS
The Special Function Registers (SFRs) are registers
used by the CPU and peripheral functions to control
the operation of the device (Table 4-1).
TABLE 4-1:
Address
N/A
SPECIAL FUNCTION REGISTER (SFR) SUMMARY
Name
TRIS
Bit 7
Bit 6
—
—
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1 Bit 0
I/O control registers
Value on
Power-On
Reset
Value on
MCLR and
WDT Reset
Value on
Wake-up on
Pin Change
--11 1111
--11 1111
--11 1111
1111 1111
1111 1111
1111 1111
N/A
OPTION
Contains control bits to configure Timer0, Timer0/WDT
prescaler, wake-up on change, and weak pull-ups
00h
INDF
Uses contents of FSR to address data memory (not a physical
register)
xxxx xxxx
uuuu uuuu
uuuu uuuu
01h
TMR0
8-bit real-time clock/counter
xxxx xxxx
uuuu uuuu
uuuu uuuu
02h(1)
PCL
Low order 8 bits of PC
1111 1111
1111 1111
1111 1111
03h
STATUS
GPWUF
0001 1xxx
000q quuu
100q quuu
04h
FSR
(12CE518) Indirect data memory address pointer
111x xxxx
111u uuuu
111u uuuu
04h
FSR
(12CE519) Indirect data memory address pointer
110x xxxx
11uu uuuu
11uu uuuu
—
PA0
TO
PD
Z
DC
C
OSCCAL
(12CE518/
12CE519)
05h
06h
GPIO
CAL7
CAL6 CAL5 CAL4 CALFST CALSLW
SCL
SDA
GP5
GP4
GP3
GP2
—
—
0111 00--
uuuu uu--
uuuu uu--
GP1 GP0 11xx xxxx
11uu uuuu
11uu uuuu
Legend: Shaded boxes = unimplemented or unused, — = unimplemented, read as '0' (if applicable)
x = unknown, u = unchanged, q = see the tables in Section 8.7 for possible values.
Note 1: The upper byte of the Program Counter is not directly accessible. See Section 4.6
for an explanation of how to access these bits.
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PIC12CE5XX
4.2.3
For example, CLRF STATUS will clear the upper three
bits and set the Z bit. This leaves the STATUS register
as 000u u1uu (where u = unchanged).
EEPROM DATA MEMORY
The PIC12CE518 and PIC12CE519 each have 16
bytes of EEPROM data memory. The EEPROM data
memory supports a bi-directional 2-wire bus and data
transmission protocol.
Refer to Section 6.0 on
EEPROM Peripherals.
4.3
It is recommended, therefore, that only BCF, BSF and
MOVWF instructions be used to alter the STATUS
register because these instructions do not affect the Z,
DC or C bits from the STATUS register. For other
instructions, which do affect STATUS bits, see
Instruction Set Summary.
STATUS Register
This register contains the arithmetic status of the ALU,
the RESET status, and the page preselect bit for
program memories larger than 512 words.
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 or C bits, then the write to these three bits is
disabled. These bits are set or cleared according to
the device logic. Furthermore, the TO and PD bits are
not writable. Therefore, the result of an instruction with
the STATUS register as destination may be different
than intended.
FIGURE 4-4:
R/W-0
GPWUF
bit7
STATUS REGISTER (ADDRESS:03h)
R/W-0
—
R/W-0
PA0
R-1
TO
R-1
PD
R/W-x
Z
R/W-x
DC
6
5
4
3
2
1
R/W-x
C
bit0
R = Readable bit
W = Writable bit
- n = Value at POR reset
bit 7:
GPWUF: GPIO reset bit
1 = Reset due to wake-up from SLEEP on pin change
0 = After power up or other reset
bit 6:
Unimplemented
bit 5:
PA0: Program page preselect bits
1 = Page 1 (200h - 3FFh) - PIC12CE519
0 = Page 0 (000h - 1FFh) - PIC12CE518 and PIC12CE519
Each page is 512 bytes.
Using the PA0 bit as a general purpose read/write bit in devices which do not use it for program
page preselect is not recommended since this may affect upward compatibility with future products.
bit 4:
TO: Time-out bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction
0 = A WDT time-out occurred
bit 3:
PD: Power-down bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction
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 ADDWF and SUBWF instructions)
ADDWF
1 = A carry from the 4th low order bit of the result occurred
0 = A carry from the 4th low order bit of the result did not occur
SUBWF
1 = A borrow from the 4th low order bit of the result did not occur
0 = A borrow from the 4th low order bit of the result occurred
bit 0:
C: Carry/borrow bit (for ADDWF, SUBWF and RRF, RLF instructions)
ADDWF
SUBWF
1 = A carry occurred
1 = A borrow did not occur
0 = A carry did not occur
0 = A borrow occurred
DS40172A-page 14
Preliminary
RRF or RLF
Load bit with LSB or MSB, respectively
 1997 Microchip Technology Inc.
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PIC12CE5XX
4.4
OPTION Register
The OPTION register is a 8-bit wide, write-only
register which contains various control bits to
configure the Timer0/WDT prescaler and Timer0.
By executing the OPTION instruction, the contents of
the W register will be transferred to the OPTION
register. A RESET sets the OPTION<7:0> bits.
FIGURE 4-5:
W-1
GPWU
bit7
Note:
If TRIS bit is set to ‘0’, the wake-up on
change and pull-up functions are disabled
for that pin; i.e., note that TRIS overrides
OPTION control of GPPU and GPWU.
Note:
If the T0CS bit is set to ‘1’, GP2 is forced to
be an input even if TRIS GP2 = ‘0’.
OPTION REGISTER
W-1
GPPU
6
W-1
T0CS
5
W-1
T0SE
4
W-1
PSA
3
W-1
PS2
2
bit 7:
GPWU: Enable wake-up on pin change (GP0, GP1, GP3)
1 = Disabled
0 = Enabled
bit 6:
GPPU: Enable weak pull-ups (GP0, GP1, GP3)
1 = Disabled
0 = Enabled
bit 5:
T0CS: Timer0 clock source select bit
1 = Transition on T0CKI pin
0 = Transition on internal instruction cycle clock, Fosc/4
bit 4:
T0SE: Timer0 source edge select bit
1 = Increment on high to low transition on the T0CKI pin
0 = Increment on low to high transition on the T0CKI pin
bit 3:
PSA: Prescaler assignment bit
1 = Prescaler assigned to the WDT
0 = Prescaler assigned to Timer0
bit 2-0:
PS2:PS0: Prescaler rate select bits
Bit Value
Timer0 Rate
WDT Rate
000
001
010
011
100
101
110
111
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
1:1
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
 1997 Microchip Technology Inc.
W-1
PS1
1
Preliminary
W-1
PS0
bit0
W = Writable bit
U = Unimplemented bit
- n = Value at POR reset
Reference Table 4-1 for
other resets.
DS40172A-page 15
12CF5XX_GEBook Page 16 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
4.5
OSCCAL Register
The Oscillator Calibration (OSCCAL) register is used to
calibrate the internal 4 MHz oscillator. It contains four
bits for fine calibration and two other bits to either
increase or decrease frequency.
FIGURE 4-6:
OSCCAL REGISTER (ADDRESS 8Fh)
R/W-0
R/W-1
R/W-1
R/W-1
R/W-0
R/W-0
U-0
U-0
CAL3
CAL2
CAL1
CAL0
CALFST
CALSLW
—
—
bit7
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit 7-4: CAL<3:0>: Fine calibration
bit 3:
CALFST: Calibration Fast
1 = Increase frequency
0 = No change
bit 2:
CALSLW: Calibration Slow
1 = Decrease frequency
0 = No change
bit 1-0: Unimplemented: Read as '0'
Note:
If CALFST = 1 and CALSLW = 1, CALFST has precedence.
DS40172A-page 16
Preliminary
 1997 Microchip Technology Inc.
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PIC12CE5XX
4.6
Program Counter
4.6.1
EFFECTS OF RESET
As a program instruction is executed, the Program
Counter (PC) will contain the address of the next
program instruction to be executed. The PC value is
increased by one every instruction cycle, unless an
instruction changes the PC.
The Program Counter is set upon a RESET, which
means that the PC addresses the last location in the
last page i.e., the oscillator calibration instruction. After
executing MOVLW XX, the PC will roll over to location
00h, and begin executing user code.
For a GOTO instruction, bits 8:0 of the PC are provided
by the GOTO instruction word. The PC Latch (PCL) is
mapped to PC<7:0>. Bit 5 of the STATUS register
provides page information to bit 9 of the PC (Figure 47).
The STATUS register page preselect bits are cleared
upon a RESET, which means that page 0 is preselected.
For a CALL instruction, or any instruction where the
PCL is the destination, bits 7:0 of the PC again are
provided by the instruction word. However, PC<8>
does not come from the instruction word, but is always
cleared (Figure 4-7).
Instructions where the PCL is the destination, or
Modify PCL instructions, include MOVWF PC, ADDWF
PC, and BSF PC,5.
Note:
Because PC<8> is cleared in the CALL
instruction, or any Modify PCL instruction,
all subroutine calls or computed jumps are
limited to the first 256 locations of any program memory page (512 words long).
FIGURE 4-7:
LOADING OF PC
BRANCH INSTRUCTIONS PIC12CE518/CE519
GOTO Instruction
11 10
9
8 7
0
PC
Therefore, upon a RESET, a GOTO instruction will
automatically cause the program to jump to page 0
until the value of the page bits is altered.
4.7
Stack
PIC12CE5XX devices have a 12-bit wide hardware
push/pop stack.
A CALL instruction will push the current value of stack
1 into stack 2 and then push the current program
counter value, incremented by one, into stack level 1. If
more than two sequential CALL’s are executed, only
the most recent two return addresses are stored.
A RETLW instruction will pop the contents of stack level
1 into the program counter and then copy stack level 2
contents into level 1. If more than two sequential
RETLW’s are executed, the stack will be filled with the
address previously stored in level 2. Note that the
W register will be loaded with the literal value specified
in the instruction. This is particularly useful for the
implementation of data look-up tables within the
program memory.
PCL
Instruction Word
PA0
7
0
STATUS
CALL or Modify PCL Instruction
11 10
9
8 7
0
PC
PCL
Instruction Word
Reset to ‘0’
PA0
7
0
STATUS
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 17
12CF5XX_GEBook Page 18 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
4.8
Indirect Data Addressing; INDF and
FSR Registers
EXAMPLE 4-2:
The INDF register is not a physical register.
Addressing INDF actually addresses the register
whose address is contained in the FSR register (FSR
is a pointer). This is indirect addressing.
EXAMPLE 4-1:
INDIRECT ADDRESSING
NEXT
movlw
movwf
clrf
incf
btfsc
goto
HOW TO CLEAR RAM
USING INDIRECT
ADDRESSING
0x10
FSR
INDF
FSR,F
FSR,4
NEXT
;initialize pointer
; to RAM
;clear INDF register
;inc pointer
;all done?
;NO, clear next
CONTINUE
•
•
•
•
Register file 07 contains the value 10h
Register file 08 contains the value 0Ah
Load the value 07 into the FSR register
A read of the INDF register will return the value
of 10h
• Increment the value of the FSR register by one
(FSR = 08)
• A read of the INDR register now will return the
value of 0Ah.
:
;YES, continue
The FSR is a 5-bit wide register. It is used in
conjunction with the INDF register to indirectly address
the data memory area.
The FSR<4:0> bits are used to select data memory
addresses 00h to 1Fh.
PIC12CE518: Does not use banking. FSR<6:5> are
unimplemented and read as '1's.
Reading INDF itself indirectly (FSR = 0) will produce
00h. Writing to the INDF register indirectly results in a
no-operation (although STATUS bits may be affected).
PIC12CE519: Uses FSR<5>. Selects between bank 0
and bank 1. FSR<6> is unimplemented, read as '1’ .
A simple program to clear RAM locations 10h-1Fh
using indirect addressing is shown in Example 4-2.
FIGURE 4-8:
DIRECT/INDIRECT ADDRESSING
Direct Addressing
(FSR)
6 5
4
bank select
location select
Indirect Addressing
(opcode)
0
6
5
4
bank
00
(FSR)
0
location select
01
00h
Addresses
map back to
addresses
in Bank 0.
Data
Memory(1)
0Fh
10h
1Fh
Bank 0
3Fh
Bank 1(2)
Note 1: For register map detail see Section 4.2.
Note 2: PIC12CE519 only
DS40172A-page 18
Preliminary
 1997 Microchip Technology Inc.
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PIC12CE5XX
5.0
PIC12CE518 I/O PORT
5.3
As with any other register, the I/O register can be
written and read under program control. However,
read instructions (e.g., MOVF GPIO,W) always read the
I/O pins independent of the pin’s input/output modes.
On RESET, all GPIO ports are defined as input (inputs
are at hi-impedance) since the I/O control registers are
all set.
5.1
The equivalent circuit for an I/O port pin is shown in
Figure 5-1. All port pins, except GP3 which is input
only, may be used for both input and output
operations. For input operations these ports are nonlatching. Any input must be present until read by an
input instruction (e.g., MOVF GPIO,W). The outputs are
latched and remain unchanged until the output latch is
rewritten. To use a port pin as output, the
corresponding direction control bit in TRIS must be
cleared (= 0). For use as an input, the corresponding
TRIS bit must be set. Any I/O pin (except GP3) can be
programmed individually as input or output.
GPIO
GPIO is an 8-bit I/O register. Only the low order 6 bits
are used (GP5:GP0) for pin control. Bits 6 and 7 (SDA
and SCL) are used by the EEPROM peripheral. Refer
to Section 6.0 and Appendix A for use of SDA and
SCL. Please note that GP3 is an input only pin. The
configuration word can set several I/O’s to alternate
functions. When acting as alternate functions the pins
will read as ‘0’ during port read. Pins GP0, GP1, and
GP3 can be configured with weak pull-ups and also
with wake-up on change. The wake-up on change and
weak pull-up functions are not pin selectable. If pin 4 is
configured as MCLR, weak pull-up is always on and
wake-up on change for this pin is not enabled.
5.2
FIGURE 5-1:
EQUIVALENT CIRCUIT
FOR A SINGLE I/O PIN
Data
Bus
D
VDD
Q
CK
P
N
W
Reg
TRIS Register
Q
Data
Latch
WR
Port
The output driver control register is loaded with the
contents of the W register by executing the TRIS f
instruction. A '1' from a TRIS register bit puts the
corresponding output driver in a hi-impedance mode.
A '0' puts the contents of the output data latch on the
selected pins, enabling the output buffer. The
exceptions are GP3 which is input only and GP2 which
may be controlled by the option register, see Figure 45.
Note:
I/O Interfacing
D
Q
TRIS
Latch
TRIS ‘f’
I/O
pin(1)
VSS
Q
CK
Reset
A read of the ports reads the pins, not the
output data latches. That is, if an output
driver on a pin is enabled and driven high,
but the external system is holding it low, a
read of the port will indicate that the pin is
low.
RD Port
Note 1: I/O pins have protection diodes to VDD and VSS.
The TRIS registers are “write-only” and are set (output
drivers disabled) upon RESET.
TABLE 5-1:
Address
SUMMARY OF PORT REGISTERS
Name
Bit 3
Bit 2
Bit 1 Bit 0
Value on
Wake-up on
Pin Change
Bit 6
—
—
--11 1111
--11 1111
--11 1111
N/A
OPTION
GPWU
GPPU
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111
1111 1111
1111 1111
03H
STATUS
GPWUF
—
PA0
TO
PD
Z
DC
C
0001 1xxx
000q quuu
100q quuu
06h
GPIO
SCL
SDA
GP5
GP4
GP3
GP2
GP1
GP0 11xx xxxx
11uu uuuu
11uu uuuu
TRIS
Bit 4
Value on
MCLR and
WDT Reset
Bit 7
N/A
Bit 5
Value on
Power-On
Reset
I/O control registers
Legend: Shaded cells not used by Port Registers, read as ‘0’, — = unimplemented, read as '0', x = unknown, u = unchanged,
q = see tables in Section 8.7 for possible values.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 19
12CF5XX_GEBook Page 20 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
5.4
I/O Programming Considerations
5.4.1
BI-DIRECTIONAL I/O PORTS
EXAMPLE 5-1:
Some instructions operate internally as read followed
by write operations. The BCF and BSF instructions, for
example, read the entire port into the CPU, execute
the bit operation and re-write the result. Caution must
be used when these instructions are applied to a port
where one or more pins are used as input/outputs. For
example, a BSF operation on bit5 of GPIO will cause all
eight bits of GPIO to be read into the CPU, bit5 to be
set and the GPIO value to be written to the output
latches. If another bit of GPIO is used as a bidirectional I/O pin (say bit0) and it is defined as an
input at this time, the input signal present on the pin
itself would be read into the CPU and rewritten to the
data latch of this particular pin, overwriting the
previous content. As long as the pin stays in the input
mode, no problem occurs. However, if bit0 is switched
into output mode later on, the content of the data latch
may now be unknown.
Example 5-1 shows the effect of two sequential readmodify-write instructions (e.g., BCF, BSF, etc.) on an I/
O port.
A pin actively outputting a high or a low should not be
driven from external devices at the same time in order
to change the level on this pin (“wired-or”, “wired-and”).
The resulting high output currents may damage the
chip.
FIGURE 5-2:
READ-MODIFY-WRITE
INSTRUCTIONS ON AN
I/O PORT
;Initial GPIO Settings
; GPIO<5:3> Inputs
; GPIO<2:0> Outputs
;
;
GPIO latch GPIO pins
;
---------- ---------BCF
GPIO, 5
;--01 -ppp
--11 pppp
BCF
GPIO, 4
;--10 -ppp
--11 pppp
MOVLW 007h
;
TRIS GPIO
;--10 -ppp
--11 pppp
;
;Note that the user may have expected the pin
;values to be --00 pppp. The 2nd BCF caused
;GP5 to be latched as the pin value (High).
5.4.2
SUCCESSIVE OPERATIONS ON I/O
PORTS
The actual write to an I/O port happens at the end of
an instruction cycle, whereas for reading, the data
must be valid at the beginning of the instruction cycle
(Figure 5-2). Therefore, care must be exercised if a
write followed by a read operation is carried out on the
same I/O port. The sequence of instructions should
allow the pin voltage to stabilize (load dependent)
before the next instruction, which causes that file to be
read into the CPU, is executed. Otherwise, the
previous state of that pin may be read into the CPU
rather than the new state. When in doubt, it is better to
separate these instructions with a NOP or another
instruction not accessing this I/O port.
SUCCESSIVE I/O OPERATION
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC
Instruction
fetched
MOVWF GPIO
PC + 1
MOVF GPIO,W
PC + 2
PC + 3
NOP
NOP
where: TCY = instruction cycle.
GP5:GP0
Port pin
written here
Instruction
executed
DS40172A-page 20
This example shows a write to GPIO followed
by a read from GPIO.
Data setup time = (0.25 TCY – TPD)
MOVWF GPIO
(Write to
GPIO)
TPD = propagation delay
Therefore, at higher clock frequencies, a
write followed by a read may be problematic.
Port pin
sampled here
MOVF GPIO,W
(Read
GPIO)
NOP
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 21 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
6.0
EEPROM PERIPHERAL
OPERATION
The PIC12CE518 and PIC12CE519 each have 16
bytes of EEPROM data memory. The EEPROM memory has an endurance of 1,000,000 erase/write cycles
and a data retention of greater than 40 years. The
EEPROM data memory supports a bi-directional 2-wire
bus and data transmission protocol. These two-wires
are serial data (SDA) and serial clock (SCL), that are
mapped to bit6 and bit7, respectively, of the GPIO register (SFR 06h). Unlike the GP0-GP5 that are connected to the I/O pins, SDA and SCL are only
connected to the internal EEPROM peripheral. For
most applications, all that is required is calls to the following functions:
; Byte_Write: Byte write routine
;
Inputs: EEPROM Address
EEADDR
;
EEPROM Data
EEDATA
;
Outputs:
Return 01 in W if OK, else
return 00 in W
;
; Read_Current: Read EEPROM at address
currently held by EE device.
;
Inputs: NONE
;
Outputs:
EEPROM Data
EEDATA
;
Return 01 in W if OK, else
return 00 in W
;
; Read_Random: Read EEPROM byte at supplied
address
;
Inputs: EEPROM Address
EEADDR
;
Outputs:
EEPROM Data
EEDATA
;
Return 01 in W if OK,
else return 00 in W
The code for these functions is listed in Appendix A,
and is accessed by either including the source code
EEPROM.INC or by linking EEPROM.ASM.
6.0.1
SERIAL DATA
SDA is a bi-directional pin used to transfer addresses
and data into and data out of the device.
For normal data transfer SDA is allowed to change only
during SCL low. Changes during SCL high are
reserved for indicating the START and STOP conditions.
6.0.2
SERIAL CLOCK
This SCL input is used to synchronize the data transfer
from and to the device.
6.1
BUS CHARACTERISTICS
The following bus protocol is to be used with the
EEPROM data memory.
During data transfer, the data line must remain stable
whenever the clock line is HIGH. Changes in the data
line while the clock line is HIGH will be interpreted as a
START or STOP condition.
Accordingly, the following bus conditions have been
defined (Figure 6-1).
6.1.1
BUS NOT BUSY (A)
Both data and clock lines remain HIGH.
6.1.2
START DATA TRANSFER (B)
A HIGH to LOW transition of the SDA line while the
clock (SCL) is HIGH determines a START condition. All
commands must be preceded by a START condition.
6.1.3
STOP DATA TRANSFER (C)
A LOW to HIGH transition of the SDA line while the
clock (SCL) is HIGH determines a STOP condition. All
operations must be ended with a STOP condition.
6.1.4
DATA VALID (D)
The state of the data line represents valid data when,
after a START condition, the data line is stable for the
duration of the HIGH period of the clock signal.
The data on the line must be changed during the LOW
period of the clock signal. There is one bit of data per
clock pulse.
Each data transfer is initiated with a START condition
and terminated with a STOP condition. The number of
the data bytes transferred between the START and
STOP conditions is determined by the master device
and is theoretically unlimited.
6.1.5
ACKNOWLEDGE
Each receiving device, when addressed, is obliged to
generate an acknowledge after the reception of each
byte. The master device must generate an extra clock
pulse which is associated with this acknowledge bit.
Note:
Acknowledge bits are generated if an internal programming cycle is in progress.
The device that acknowledges has to pull down the
SDA line during the acknowledge clock pulse in such a
way that the SDA line is stable LOW during the HIGH
period of the acknowledge related clock pulse. Of
course, setup and hold times must be taken into
account. A master must signal an end of data to the
slave by not generating an acknowledge bit on the last
byte that has been clocked out of the slave. In this case,
the slave must leave the data line HIGH to enable the
master to generate the STOP condition (Figure 6-2).
• Data transfer may be initiated only when the bus
is not busy.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 21
12CF5XX_GEBook Page 22 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 6-1:
SCL
(A)
DATA TRANSFER SEQUENCE ON THE SERIAL BUS
(B)
(C)
(D)
START
CONDITION
ADDRESS OR
ACKNOWLEDGE
VALID
(C)
(A)
SDA
FIGURE 6-2:
STOP
CONDITION
DATA
ALLOWED
TO CHANGE
ACKNOWLEDGE TIMING
Acknowledge
Bit
1
SCL
2
SDA
3
4
5
6
7
8
9
1
Device Addressing
Receiver must release the SDA line at this point
so the Transmitter can continue sending data.
FIGURE 6-3:
The last bit of the control byte determines the operation
to be performed. When set to a one a read operation is
selected, and when set to a zero a write operation is
selected. (Figure 6-3). The bus is monitored for its corresponding slave address all the time. It generates an
acknowledge bit if the slave address was true and it is
not in a programming mode.
CONTROL BYTE FORMAT
Read/Write Bit
After generating a START condition, the bus master
transmits a control byte consisting of a slave address
and a Read/Write bit that indicates what type of operation is to be performed. The slave address consists of a
4-bit device code (1010) followed by three don't care
bits.
DS40172A-page 22
3
Data from transmitter
Data from transmitter
Transmitter must release the SDA line at this point
allowing the Receiver to pull the SDA line low to
acknowledge the previous eight bits of data.
6.2
2
Don’t Care
Bits
Device Select
Bits
S
1
0
1
0
X
X
X R/W ACK
Slave Address
Start Bit
Preliminary
Acknowledge Bit
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 23 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
6.3
WRITE OPERATIONS
6.4
6.3.1
BYTE WRITE
Since the device will not acknowledge during a write
cycle, this can be used to determine when the cycle is
complete (this feature can be used to maximize bus
throughput). Once the stop condition for a write command has been issued from the master, the device initiates the internally timed write cycle. ACK polling can
be initiated immediately. This involves the master sending a start condition followed by the control byte for a
write command (R/W = 0). If the device is still busy with
the write cycle, then no ACK will be returned. If no ACK
is returned, then the start bit and control byte must be
re-sent. If the cycle is complete, then the device will
return the ACK and the master can then proceed with
the next read or write command. See Figure 6-4 for
flow diagram.
Following the start signal from the master, the device
code (4 bits), the don't care bits (3 bits), and the R/W
bit (which is a logic low) are placed onto the bus by the
master transmitter. This indicates to the addressed
slave receiver that a byte with a word address will follow
after it has generated an acknowledge bit during the
ninth clock cycle. Therefore, the next byte transmitted
by the master is the word address and will be written
into the address pointer. Only the lower four address
bits are used by the device, and the upper four bits are
don’t cares. The address byte is acknowledgeable and
the master device will then transmit the data word to be
written into the addressed memory location. The memory acknowledges again and the master generates a
stop condition. This initiates the internal write cycle,
and during this time will not generate acknowledge signals (Figure 6-5). After a byte write command, the internal address counter will not be incremented and will
point to the same address location that was just written.
If a stop bit is transmitted to the device at any point in
the write command sequence before the entire
sequence is complete, then the command will abort
and no data will be written. If more than 8 data bits are
transmitted before the stop bit is sent, then the device
will clear the previously loaded byte and begin loading
the data buffer again. If more than one data byte is
transmitted to the device and a stop bit is sent before a
full eight data bits have been transmitted, then the write
command will abort and no data will be written. The
EEPROM memory employs a VCC threshold detector
circuit which disables the internal erase/write logic if
the VCC is below minimum VDD.
ACKNOWLEDGE POLLING
FIGURE 6-4:
ACKNOWLEDGE POLLING
FLOW
Send
Write Command
Send Stop
Condition to
Initiate Write Cycle
Send Start
Send Control Byte
with R/W = 0
Did Device
Acknowledge
(ACK = 0)?
NO
YES
Next
Operation
FIGURE 6-5:
BYTE WRITE
BUS ACTIVITY
MASTER
S
T
A
R
T
SDA LINE
S
CONTROL
BYTE
1
0
1
0
BUS ACTIVITY
X
X
WORD
ADDRESS
X
X
0
X
X
S
T
O
P
DATA
P
X
A
C
K
A
C
K
A
C
K
X = Don’t Care Bit
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 23
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PIC12CE5XX
6.5
READ OPERATIONs
device as part of a write operation. After the word
address is sent, the master generates a start condition
following the acknowledge. This terminates the write
operation, but not before the internal address pointer is
set. Then the master issues the control byte again but
with the R/W bit set to a one. It will then issue an
acknowledge and transmits the eight bit data word. The
master will not acknowledge the transfer but does generate a stop condition and the device discontinues
transmission (Figure 6-7). After this command, the
internal address counter will point to the address location following the one that was just read.
Read operations are initiated in the same way as write
operations with the exception that the R/W bit of the
slave address is set to one. There are three basic types
of read operations: current address read, random read,
and sequential read.
6.5.1
CURRENT ADDRESS READ
It contains an address counter that maintains the
address of the last word accessed, internally incremented by one. Therefore, if the previous read access
was to address n, the next current address read operation would access data from address n + 1. Upon
receipt of the slave address with the R/W bit set to one,
the device issues an acknowledge and transmits the
eight bit data word. The master will not acknowledge
the transfer but does generate a stop condition and the
device discontinues transmission (Figure 6-6).
6.5.2
6.5.3
Sequential reads are initiated in the same way as a random read except that after the device transmits the first
data byte, the master issues an acknowledge as
opposed to a stop condition in a random read. This
directs the device to transmit the next sequentially
addressed 8-bit word (Figure 6-8).
RANDOM READ
To provide sequential reads, it contains an internal
address pointer which is incremented by one at the
completion of each read operation. This address
pointer allows the entire memory contents to be serially
read during one operation.
Random read operations allow the master to access
any memory location in a random manner. To perform
this type of read operation, first the word address must
be set. This is done by sending the word address to the
FIGURE 6-6:
SEQUENTIAL READ
CURRENT ADDRESS READ
BUS ACTIVITY
MASTER
S
T
A
R
T
SDA LINE
S 1 0 1 0 X XX 1
S
T
O
P
CONTROL
BYTE
P
A
C
K
BUS ACTIVITY
N
O
A
C
K
DATA
X = Don’t Care Bit
FIGURE 6-7:
RANDOM READ
BUS ACTIVITY
MASTER
S
T
A
R
T
CONTROL
BYTE
X X X X
S 1 0 1 0 X X X 0
SDA LINE
S
T
O
P
CONTROL
BYTE
P
S 1 0 1 0 X X X 1
A
C
K
A
C
K
BUS ACTIVITY
S
T
A
R
T
WORD
ADDRESS (n)
A
C
K
A
C
K
X = Don’t Care Bit
FIGURE 6-8:
BUS ACTIVITY
MASTER
DATA (n)
N
O
SEQUENTIAL READ
CONTROL
BYTE
DATA n
DATA n + 1
DATA n + 2
S
T
O
P
DATA n + X
P
SDA LINE
BUS ACTIVITY
DS40172A-page 24
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C
K
A
C
K
A
C
K
Preliminary
A
C
K
N
O
A
C
K
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 25 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
7.0
TIMER0 MODULE AND
TMR0 REGISTER
Counter mode is selected by setting the T0CS bit
(OPTION<5>). In this mode, Timer0 will increment
either on every rising or falling edge of pin T0CKI. The
T0SE bit (OPTION<4>) determines the source edge.
Clearing the T0SE bit selects the rising edge.
Restrictions on the external clock input are discussed
in detail in Section 7.1.
The Timer0 module has the following features:
• 8-bit timer/counter register, TMR0
- Readable and writable
• 8-bit software programmable prescaler
• Internal or external clock select
- Edge select for external clock
Figure 7-1 is a simplified block diagram of the Timer0
module.
Timer mode is selected by clearing the T0CS bit
(OPTION<5>). In timer mode, the Timer0 module will
increment every instruction cycle (without prescaler). If
TMR0 register is written, the increment is inhibited for
the following two cycles (Figure 7-2 and Figure 7-3).
The user can work around this by writing an adjusted
value to the TMR0 register.
FIGURE 7-1:
The prescaler may be used by either the Timer0
module or the Watchdog Timer, but not both. The
prescaler assignment is controlled in software by the
control bit PSA (OPTION<3>). Clearing the PSA bit
will assign the prescaler to Timer0. The prescaler is
not readable or writable. When the prescaler is
assigned to the Timer0 module, prescale values of 1:2,
1:4,..., 1:256 are selectable. Section 7.2 details the
operation of the prescaler.
A summary of registers associated with the Timer0
module is found in Table 7-1.
TIMER0 BLOCK DIAGRAM
Data bus
GP2/T0CKI
Pin
FOSC/4
0
PSout
1
1
Programmable
Prescaler(2)
0
T0SE
8
Sync with
Internal
Clocks
TMR0 reg
PSout
(2 cycle delay) Sync
3
T0CS(1)
PS2, PS1, PS0(1)
PSA(1)
Note 1: Bits T0CS, T0SE, PSA, PS2, PS1 and PS0 are located in the OPTION register.
2: The prescaler is shared with the Watchdog Timer (Figure 7-5).
 1997 Microchip Technology Inc.
Preliminary
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PIC12CE5XX
FIGURE 7-2:
TIMER0 TIMING: INTERNAL CLOCK/NO PRESCALE
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
PC
(Program
Counter)
PC-1
Instruction
Fetch
PC
PC+1
MOVWF TMR0
MOVF TMR0,W
T0
Timer0
T0+1
Instruction
Executed
FIGURE 7-3:
PC+4
T0+2
NT0
NT0
Write TMR0
executed
Read TMR0
reads NT0
Read TMR0
reads NT0
PC+5
MOVF TMR0,W
NT0
NT0+1
Read TMR0
reads NT0 + 1
Read TMR0
reads NT0
PC+6
MOVF TMR0,W
NT0+2
Read TMR0
reads NT0 + 2
TIMER0 TIMING: INTERNAL CLOCK/PRESCALE 1:2
PC-1
Instruction
Fetch
PC
PC+1
MOVWF TMR0
MOVF TMR0,W
Instruction
Execute
PC+4
PC+5
MOVF TMR0,W
Read TMR0
reads NT0
Read TMR0
reads NT0
PC+6
MOVF TMR0,W
NT0+1
Read TMR0
reads NT0
Read TMR0
reads NT0
T0
Read TMR0
reads NT0 + 1
REGISTERS ASSOCIATED WITH TIMER0
Name
TMR0
PC+3
MOVF TMR0,W
NT0
Write TMR0
executed
TABLE 7-1:
PC+2
MOVF TMR0,W
T0+1
T0
Timer0
01h
PC+3
MOVF TMR0,W
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
PC
(Program
Counter)
Address
PC+2
MOVF TMR0,W
Bit 7
Bit 6
Bit 5
Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Timer0 - 8-bit real-time clock/counter
N/A
OPTION GPWU GPPU T0CS T0SE PSA PS2
N/A
TRIS
I/O control registers
Value on
Power-On
Reset
Value on
Value on
MCLR and Wake-up on
WDT Reset Pin Change
xxxx xxxx uuuu uuuu uuuu uuuu
PS1
PS0 1111 1111 1111 1111 1111 1111
--11 1111 --11 1111 --11 1111
Legend: Shaded cells not used by Timer0, - = unimplemented, x = unknown, u = unchanged,
DS40172A-page 26
Preliminary
 1997 Microchip Technology Inc.
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PIC12CE5XX
7.1
Using Timer0 with an External Clock
When a prescaler is used, the external clock input is
divided by the asynchronous ripple counter-type
prescaler so that the prescaler output is symmetrical.
For the external clock to meet the sampling
requirement, the ripple counter must be taken into
account. Therefore, it is necessary for T0CKI to have a
period of at least 4TOSC (and a small RC delay of
40 ns) divided by the prescaler value. The only
requirement on T0CKI high and low time is that they
do not violate the minimum pulse width requirement of
10 ns. Refer to parameters 40, 41 and 42 in the
electrical specification of the desired device.
When an external clock input is used for Timer0, it
must meet certain requirements. The external clock
requirement is due to internal phase clock (TOSC)
synchronization. Also, there is a delay in the actual
incrementing of Timer0 after synchronization.
7.1.1
EXTERNAL CLOCK SYNCHRONIZATION
When no prescaler is used, the external clock input is
the same as the prescaler output. The synchronization
of T0CKI with the internal phase clocks is
accomplished by sampling the prescaler output on the
Q2 and Q4 cycles of the internal phase clocks
(Figure 7-4). Therefore, it is necessary for T0CKI to be
high for at least 2TOSC (and a small RC delay of 20 ns)
and low for at least 2TOSC (and a small RC delay of
20 ns). Refer to the electrical specification of the
desired device.
7.1.2
TIMER0 INCREMENT DELAY
Since the prescaler output is synchronized with the
internal clocks, there is a small delay from the time the
external clock edge occurs to the time the Timer0
module is actually incremented. Figure 7-4 shows the
delay from the external clock edge to the timer
incrementing.
7.1.3
OPTION REGISTER EFFECT ON GP2 TRIS
If the option register is set to read TIMER0 from the pin,
the port is forced to an input regardless of the TRIS register setting.
FIGURE 7-4:
TIMER0 TIMING WITH EXTERNAL CLOCK
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4
External Clock Input or
Prescaler Output (2)
Q1 Q2 Q3 Q4
Small pulse
misses sampling
(1)
External Clock/Prescaler
Output After Sampling
(3)
Increment Timer0 (Q4)
Timer0
T0
T0 + 1
T0 + 2
Note 1: Delay from clock input change to Timer0 increment is 3Tosc to 7Tosc. (Duration of Q = Tosc).
Therefore, the error in measuring the interval between two edges on Timer0 input = ± 4Tosc max.
2: External clock if no prescaler selected, Prescaler output otherwise.
3: The arrows indicate the points in time where sampling occurs.
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Preliminary
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PIC12CE5XX
7.2
Prescaler
EXAMPLE 7-1:
An 8-bit counter is available as a prescaler for the
Timer0 module, or as a postscaler for the Watchdog
Timer (WDT), respectively (Section 8.6). For simplicity,
this counter is being referred to as “prescaler”
throughout this data sheet. Note that the prescaler
may be used by either the Timer0 module or the WDT,
but not both. Thus, a prescaler assignment for the
Timer0 module means that there is no prescaler for
the WDT, and vice-versa.
1.CLRWDT
;Clear WDT
2.CLRF
TMR0
;Clear TMR0 & Prescaler
3.MOVLW '00xx1111’b; ;These 3 lines (5, 6, 7)
4.OPTION
; are required only if
; desired
5.CLRWDT
;PS<2:0> are 000 or 001
6.MOVLW '00xx1xxx’b ;Set Postscaler to
7.OPTION
; desired WDT rate
To change prescaler from the WDT to the Timer0
module, use the sequence shown in Example 7-2. This
sequence must be used even if the WDT is disabled. A
CLRWDT instruction should be executed before switching
the prescaler.
The PSA and PS2:PS0 bits (OPTION<3:0>)
determine prescaler assignment and prescale ratio.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g., CLRF 1, MOVWF 1,
BSF 1,x, etc.) will clear the prescaler. When assigned
to WDT, a CLRWDT instruction will clear the prescaler
along with the WDT. The prescaler is neither readable
nor writable. On a RESET, the prescaler contains all
'0's.
7.2.1
EXAMPLE 7-2:
CHANGING PRESCALER
(WDT→TIMER0)
CLRWDT
MOVLW
'xxxx0xxx'
SWITCHING PRESCALER ASSIGNMENT
;Clear WDT and
;prescaler
;Select TMR0, new
;prescale value and
;clock source
OPTION
The prescaler assignment is fully under software control
(i.e., it can be changed “on the fly” during program
execution). To avoid an unintended device RESET, the
following instruction sequence (Example 7-1) must be
executed when changing the prescaler assignment from
Timer0 to the WDT.
FIGURE 7-5:
CHANGING PRESCALER
(TIMER0→WDT)
BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER
TCY ( = Fosc/4)
Data Bus
0
GP2/T0CKI
Pin
1
8
M
U
X
1
M
U
X
0
T0SE
T0CS
0
Watchdog
Timer
1
M
U
X
Sync
2
Cycles
TMR0 reg
PSA
8-bit Prescaler
8
8 - to - 1MUX
PS2:PS0
PSA
WDT Enable bit
1
0
MUX
PSA
WDT
Time-Out
Note: T0CS, T0SE, PSA, PS2:PS0 are bits in the OPTION register.
DS40172A-page 28
Preliminary
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PIC12CE5XX
8.0
SPECIAL FEATURES OF THE
CPU
The PIC12CE5XX has a Watchdog Timer which can
be shut off only through configuration bit WDTE. It
runs off of its own RC oscillator for added reliability. If
using XT or LP selectable oscillator options, there is
always an 18 ms (nominal) delay provided by the
Device Reset Timer (DRT), intended to keep the chip
in reset until the crystal oscillator is stable. If using
INTRC or EXTRC there is an 18 ms delay only on VDD
power-up. With this timer on-chip, most applications
need no external reset circuitry.
What sets a microcontroller apart from other
processors are special circuits to deal with the needs
of real-time applications. The PIC12CE5XX family of
microcontrollers has a host of such features intended
to maximize system reliability, minimize cost through
elimination of external components, provide power
saving operating modes and offer code protection.
These features are:
The SLEEP mode is designed to offer a very low
current power-down mode. The user can wake-up
from SLEEP through a change on input pins or
through a Watchdog Timer time-out. Several oscillator
options are also made available to allow the part to fit
the application, including an internal 4 MHz oscillator.
The EXTRC oscillator option saves system cost while
the LP crystal option saves power. A set of
configuration bits are used to select various options.
• Oscillator selection
• Reset
- Power-On Reset (POR)
- Device Reset Timer (DRT)
- Wake-up from SLEEP on pin change
• Watchdog Timer (WDT)
• SLEEP
• Code protection
• ID locations
• In-circuit Serial Programming
FIGURE 8-1:
8.1
Configuration Bits
The PIC12CE5XX configuration word consists of 5
bits. Configuration bits can be programmed to select
various device configurations. Two bits are for the
selection of the oscillator type, one bit is the Watchdog
Timer enable bit, and one bit is the MCLR enable bit.
One bit is the code protection bit (Figure 8-1).
CONFIGURATION WORD FOR PIC12CE5XX
—
—
—
—
—
—
—
MCLRE
CP
bit11
10
9
8
7
6
5
4
3
WDTE FOSC1 FOSC0
2
1
bit0
Register:
Address(1):
CONFIG
FFFh
bit 11-5: Unimplemented
bit 4:
MCLRE: MCLR enable bit.
1 = MCLR pin enabled
0 = MCLR tied to VDD, (Internally)
bit 3:
CP: Code protection bit.
1 = Code protection off
0 = Code protection on
bit 2:
WDTE: Watchdog timer enable bit
1 = WDT enabled
0 = WDT disabled
bit 1-0:
FOSC1:FOSC0: Oscillator selection bits
11 = EXTRC - external RC oscillator
10 = INTRC - internal RC oscillator
01 = XT oscillator
00 = LP oscillator
Note 1: Refer to the PIC12C5XX Programming Specifications to determine how to access the
configuration word. This register is not user addressable during device operation. Refer to
In-Circuit Serial Programming™ Guide.
 1997 Microchip Technology Inc.
Preliminary
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PIC12CE5XX
8.2
Oscillator Configurations
8.2.1
OSCILLATOR TYPES
TABLE 8-1:
The PIC12CE5XX can be operated in four different
oscillator modes. The user can program two
configuration bits (FOSC1:FOSC0) to select one of
these four modes:
•
•
•
•
LP:
XT:
INTRC:
EXTRC:
8.2.2
Low Power Crystal
Crystal/Resonator
Internal 4 MHz Oscillator
External Resistor/Capacitor
Osc
Type
CRYSTAL OPERATION (OR
CERAMIC RESONATOR) (XT
OR LP OSC
CONFIGURATION)
C1(1)
OSC1
Cap. Range
C1
Cap. Range
C2
XT
4.0 MHz
30 pF
30 pF
These values are for design guidance only. Since
each resonator has its own characteristics, the user
should consult the resonator manufacturer for
appropriate values of external components.
CRYSTAL OSCILLATOR / CERAMIC
RESONATORS
FIGURE 8-2:
Resonator
Freq
TABLE 8-2:
In XT or LP modes, a crystal or ceramic resonator is
connected to the GP5/OSC1/CLKIN and GP4/OSC2
pins to establish oscillation (Figure 8-2). The
PIC12CE5XX oscillator design requires the use of a
parallel cut crystal. Use of a series cut crystal may
give a frequency out of the crystal manufacturers
specifications. When in XT or LP modes, the device
can have an external clock source drive the GP5/
OSC1/CLKIN pin (Figure 8-3).
CAPACITOR SELECTION
FOR CERAMIC RESONATORS
- PIC12CE5XX
Osc
Type
CAPACITOR SELECTION
FOR CRYSTAL OSCILLATOR
- PIC12CE5XX
Resonator
Freq
Cap.Range
C1
Cap. Range
C2
15 pF
15 pF
32 kHz(1)
200 kHz
47-68 pF
47-68 pF
1 MHz
15 pF
15 pF
4 MHz
15 pF
15 pF
Note 1: For VDD > 4.5V, C1 = C2 ≈ 30 pF is
recommended.
These values are for design guidance only. Rs may
be required in XT mode to avoid overdriving crystals
with low drive level specification. Since each crystal
has its own characteristics, the user should consult
the crystal manufacturer for appropriate values of
external components.
LP
XT
PIC12CE5XX
SLEEP
XTAL
RS(2)
RF(3)
OSC2
To internal
logic
C2(1)
Note 1: See Capacitor Selection tables for
recommended values of C1 and C2.
2: A series resistor (RS) may be required for
AT strip cut crystals.
3: RF varies with the crystal chosen
(approx. value = 10 MΩ).
FIGURE 8-3:
EXTERNAL CLOCK INPUT
OPERATION (XT OR LP OSC
CONFIGURATION)
OSC1
PIC12CE5XX
Clock from
ext. system
Open
DS40172A-page 30
OSC2
Preliminary
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PIC12CE5XX
8.2.3
EXTERNAL CRYSTAL OSCILLATOR
CIRCUIT
8.2.4
Either a prepackaged oscillator or a simple oscillator
circuit with TTL gates can be used as an external
crystal oscillator circuit. Prepackaged oscillators
provide a wide operating range and better stability. A
well-designed crystal oscillator will provide good
performance with TTL gates. Two types of crystal
oscillator circuits can be used: one with parallel
resonance, or one with series resonance.
Figure 8-4 shows implementation of a parallel
resonant oscillator circuit. The circuit is designed to
use the fundamental frequency of the crystal. The
74AS04 inverter performs the 180-degree phase shift
that a parallel oscillator requires. The 4.7 kΩ resistor
provides the negative feedback for stability. The 10 kΩ
potentiometers bias the 74AS04 in the linear region.
This circuit could be used for external oscillator
designs.
FIGURE 8-4:
EXTERNAL PARALLEL
RESONANT CRYSTAL
OSCILLATOR CIRCUIT
+5V
To Other
Devices
10k
74AS04
4.7k
74AS04
PIC12CE5XX
10k
10k
20 pF
Figure 8-5 shows a series resonant oscillator circuit.
This circuit is also designed to use the fundamental
frequency of the crystal. The inverter performs a 180degree phase shift in a series resonant oscillator
circuit. The 330 Ω resistors provide the negative
feedback to bias the inverters in their linear region.
FIGURE 8-5:
74AS04
74AS04
74AS04
Although the oscillator will operate with no external
capacitor (Cext = 0 pF), we recommend using values
above 20 pF for noise and stability reasons. With no or
small external capacitance, the oscillation frequency
can vary dramatically due to changes in external
capacitances, such as PCB trace capacitance or
package lead frame capacitance.
Also, see the Electrical Specifications sections for
variation of oscillator frequency due to VDD for given
Rext/Cext values as well as frequency variation due to
operating temperature for given R, C, and VDD values.
FIGURE 8-6:
EXTERNAL RC OSCILLATOR
MODE
VDD
OSC1
To Other
Devices
330
Figure 8-6 shows how the R/C combination is
connected to the PIC12CE5XX. For Rext values below
2.2 kΩ, the oscillator operation may become unstable,
or stop completely. For very high Rext values
(e.g., 1 MΩ) the oscillator becomes sensitive to noise,
humidity and leakage. Thus, we recommend keeping
Rext between 3 kΩ and 100 kΩ.
Rext
EXTERNAL SERIES
RESONANT CRYSTAL
OSCILLATOR CIRCUIT
330
For timing insensitive applications, the RC device
option 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.
The Electrical Specifications sections show RC
frequency variation from part to part due to normal
process variation. The variation is larger for larger R
(since leakage current variation will affect RC
frequency more for large R) and for smaller C (since
variation of input capacitance will affect RC frequency
more).
CLKIN
XTAL
20 pF
EXTERNAL RC OSCILLATOR
Cext
PIC12CE5XX
Internal
clock
N
PIC12CE5XX
VSS
CLKIN
0.1 µF
XTAL
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Preliminary
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PIC12CE5XX
8.2.5
INTERNAL 4 MHz RC OSCILLATOR
The internal RC oscillator provides a fixed 4 MHz (nominal) system clock at VDD = 5V and 25°C, see “Electrical Specifications” section for information on variation
over voltage and temperature..
resumption of normal operation. The exceptions to this
are TO, PD, and GPWUF bits. They are set or cleared
differently in different reset situations. These bits are
used in software to determine the nature of reset. See
Table 8-3 for a full description of reset states of all
registers.
In addition, a calibration instruction is programmed into
the top of memory which contains the calibration value
for the internal RC oscillator. This value is programmed
as a MOVLW XX instruction where XX is the calibration
value, and is placed at the reset vector. This will load
the W register with the calibration value upon reset and
the PC will then roll over to the users program at
address 0x000. The user then has the option of writing
the value to the OSCCAL Register (05h) or ignoring it.
OSCCAL, when written to with the calibration value, will
“trim” the internal oscillator to remove process variation
from the oscillator frequency. .
Note:
Please note that erasing the device will
also erase the pre-programmed internal
calibration value for the internal oscillator.
The calibration value must be saved prior
to erasing the part.
For the PIC12CE518 and PIC12CE519, bits <7:4>,
CAL3-CAL0 are used for fine calibration while bit 3,
CALFST, and bit 2,CALSLW are used for more coarse
adjustment. Adjusting CAL3-0 from 0000 to 1111
yields a higher clock speed. Set CALFST = 1 for
greater increase in frequency or set CALSLW = 1 for
greater decrease in frequency. Note that bits 1 and 0
of OSCCAL are unimplemented and should be written
as 0 when modifying OSCALL for compatibility with
future devices.
For the PIC12CE518 and PIC12CE519, the upper 4
bits of the register are used to allow for future, longer bit
length calibration schemes. Writing a larger value in
this location yields a higher clock speed.
8.3
RESET
The device differentiates between various kinds of
reset:
a) Power on reset (POR)
b) MCLR reset during normal operation
c) MCLR reset during SLEEP
d) WDT time-out reset during normal operation
e) WDT time-out reset during SLEEP
f) Wake-up from SLEEP on pin change
Some registers are not reset in any way; they are
unknown on POR and unchanged in any other reset.
Most other registers are reset to “reset state” on poweron reset (POR), on MCLR, WDT or wake-up on pin
change reset during normal operation. They are not
affected by a WDT reset during SLEEP or MCLR reset
during SLEEP, since these resets are viewed as
DS40172A-page 32
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 33 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
TABLE 8-3:
RESET CONDITIONS FOR REGISTERS
Register
Address
Power-on Reset
MCLR Reset
WDT time-out
Wake-up on Pin Change
qqqq uuuu (1)
W
—
qqqq xxxx (1)
INDF
00h
xxxx xxxx
uuuu uuuu
TMR0
01h
xxxx xxxx
uuuu uuuu
PC
02h
1111 1111
1111 1111
STATUS
03h
0001 1xxx
?00? ?uuu (2)
FSR (12CF518)
04h
111x xxxx
111u uuuu
FSR (12CF519)
04h
110x xxxx
11uu uuuu
OSCCAL
05h
0111 00--
uuuu uu--
GPIO
06h
11xx xxxx
11uu uuuu
OPTION
—
1111 1111
1111 1111
TRIS
—
--11 1111
--11 1111
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, ? = value depends on condition.
Note 1:
Bits <7:4> of W register contain oscillator calibration values due to MOVLW XX instruction at top of memory.
Note 2:
See Table 8-7 for reset value for specific conditions
TABLE 8-4:
RESET CONDITION FOR SPECIAL REGISTERS
STATUS Addr: 03h
PCL Addr: 02h
Power on reset
0001 1xxx
1111 1111
MCLR reset during normal operation
000u uuuu
1111 1111
MCLR reset during SLEEP
0001 0uuuu
1111 1111
WDT reset during SLEEP
0000 0uuu
1111 1111
WDT reset normal operation
0000 1uuu
1111 1111
Wake-up from SLEEP on pin change
1001 0uuu
1111 1111
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 33
12CF5XX_GEBook Page 34 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
8.3.1
MCLR ENABLE
This configuration bit when unprogrammed (left in the
‘1’ state) enables the external MCLR function. When
programmed, the MCLR function is tied to the internal
VDD, and the pin is assigned to be a GPIO. See
Figure 8-7.
FIGURE 8-7:
MCLR SELECT
A power-up example where MCLR is held low is
shown in Figure 8-9. VDD is allowed to rise and
stabilize before bringing MCLR high. The chip will
actually come out of reset TDRT msec after MCLR
goes high.
MCLRE
WEAK
PULL-UP
GP3/MCLR/VPP
8.4
The Power-On Reset circuit and the Device Reset
Timer (Section 8.5) circuit are closely related. On
power-up, the reset latch is set and the DRT is reset.
The DRT timer begins counting once it detects MCLR
to be high. After the time-out period, which is typically
18 ms, it will reset the reset latch and thus end the onchip reset signal.
INTERNAL MCLR
Power-On Reset (POR)
The PIC12CE5XX family incorporates on-chip PowerOn Reset (POR) circuitry which provides an internal
chip reset for most power-up situations.
A Power-on Reset pulse is generated on-chip when
VDD rise is detected (in the range of 1.5V - 2.1V). To
take advantage of the internal POR, program the GP3/
MCLR/VPP pin as MCLR and tie directly to VDD or program the pin as GP3. An internal weak pull-up resistor
is implemented using a transistor. Refer to Table 11-7
for the pull-up resistor ranges. This will eliminate external RC components usually needed to create a Poweron Reset. A maximum rise time for VDD is specified.
See Electrical Specifications for details.
When the device starts normal operation (exits the
reset condition), device operating parameters (voltage,
frequency, temperature, ...) must be met to ensure
operation. If these conditions are not met, the device
must be held in reset until the operating parameters are
met.
In Figure 8-10, the on-chip Power-On Reset feature is
being used (MCLR and VDD are tied together or the
pin is programmed to be GP3.). The VDD is stable
before the start-up timer times out and there is no
problem in getting a proper reset. However, Figure 811 depicts a problem situation where VDD rises too
slowly. The time between when the DRT senses that
MCLR is high and when MCLR (and VDD) actually
reach their full value, is too long. In this situation, when
the start-up timer times out, VDD has not reached the
VDD (min) value and the chip is, therefore, not
guaranteed to function correctly. For such situations,
we recommend that external RC circuits be used to
achieve longer POR delay times (Figure 8-10).
Note:
When the device starts normal operation
(exits the reset condition), device operating parameters (voltage, frequency, temperature, etc.) must be meet to ensure
operation. If these conditions are not met,
the device must be held in reset until the
operating conditions are met.
For additional information refer to Application Notes
“Power-Up Considerations” - AN522 and “Power-up
Trouble Shooting” - AN607.
A simplified block diagram of the on-chip Power-On
Reset circuit is shown in Figure 8-8.
DS40172A-page 34
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 35 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 8-8:
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
Power-Up
Detect
POR (Power-On Reset)
VDD
Pin Change
Wake-up on
pin change
SLEEP
GP3/MCLR/VPP
WDT Time-out
MCLRE
RESET
8-bit Asynch
Ripple Counter
(Start-Up Timer)
On-Chip
DRT OSC
S
Q
R
Q
CHIP RESET
FIGURE 8-9:
TIME-OUT SEQUENCE ON POWER-UP (MCLR PULLED LOW)
VDD
MCLR
INTERNAL POR
TDRT
DRT TIME-OUT
INTERNAL RESET
FIGURE 8-10: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD): FAST VDD RISE TIME
VDD
MCLR
INTERNAL POR
TDRT
DRT TIME-OUT
INTERNAL RESET
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 35
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PIC12CE5XX
FIGURE 8-11: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD): SLOW VDD RISE TIME
V1
VDD
MCLR
INTERNAL POR
TDRT
DRT TIME-OUT
INTERNAL RESET
When VDD rises slowly, the TDRT time-out expires long before VDD has reached its final value. In
this example, the chip will reset properly if, and only if, V1 ≥ VDD min.
8.5
Device Reset Timer (DRT)
TABLE 8-5:
In the PIC12CE5XX, the DRT runs any time the device
is powered up. DRT runs from RESET and varies
based on oscillator selection (see Table 8-5.)
The Device Reset Timer (DRT) provides a fixed 18 ms
nominal time-out on reset. The DRT operates on an
internal RC oscillator. The processor is kept in RESET
as long as the DRT is active. The DRT delay allows
VDD to rise above VDD min., and for the oscillator to
stabilize.
Oscillator
Configuration
DRT (DEVICE RESET TIMER
PERIOD)
POR Reset
Subsequent
Resets
IntRC &
ExtRC
18 ms (typical)
300 µs
(typical)
XT & LP
18 ms (typical)
18 ms (typical)
Oscillator circuits based on crystals or ceramic
resonators require a certain time after power-up to
establish a stable oscillation. The on-chip DRT keeps
the device in a RESET condition for approximately 18
ms after MCLR has reached a logic high level. Thus,
programming GP3/MCLR/VPP as MCLR and using an
external RC network connected to the MCLR input is
not required in most cases, allowing for savings in
cost-sensitive and/or space restricted applications, as
well as allowing the use of the GP3/MCLR/VPP pin as
a general purpose input.
8.6
The Device Reset time delay will vary from chip to chip
due to VDD, temperature, and process variation. See
AC parameters for details.
The TO bit (STATUS<4>) will be cleared upon a
Watchdog Timer reset.
The DRT will also be triggered upon a Watchdog Timer
time-out (only in XT and LP modes). This is
particularly important for applications using the WDT
to wake from SLEEP mode automatically.
DS40172A-page 36
Watchdog Timer (WDT)
The Watchdog Timer (WDT) is a free running on-chip
RC oscillator which does not require any external
components. This RC oscillator is separate from the
external RC oscillator of the GP5/OSC1/CLKIN pin
and the internal 4 MHz oscillator. That means that the
WDT will run even if the main processor clock has
been stopped, for example, by execution of a SLEEP
instruction. During normal operation or SLEEP, a WDT
reset or wake-up reset generates a device RESET.
The WDT can be permanently disabled by
programming the configuration bit WDTE as a '0'
(Section 8.1). Refer to the PIC12CE5XX Programming
Specifications to determine how to access the
configuration word.
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 37 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
8.6.1
8.6.2
WDT PERIOD
WDT PROGRAMMING CONSIDERATIONS
The CLRWDT instruction clears the WDT and the
postscaler, if assigned to the WDT, and prevents it
from timing out and generating a device RESET.
The WDT has a nominal time-out period of 18 ms,
(with no prescaler). If a longer time-out period is
desired, a prescaler with a division ratio of up to 1:128
can be assigned to the WDT (under software control)
by writing to the OPTION register. Thus, a time-out
period of a nominal 2.3 seconds can be realized.
These periods vary with temperature, VDD and part-topart process variations (see DC specs).
The SLEEP instruction resets the WDT and the
postscaler, if assigned to the WDT. This gives the
maximum SLEEP time before a WDT wake-up reset.
Under worst case conditions (VDD = Min., Temperature
= Max., max. WDT prescaler), it may take several
seconds before a WDT time-out occurs.
FIGURE 8-12: WATCHDOG TIMER BLOCK DIAGRAM
From Timer0 Clock Source
(Figure 7-5)
0
1
Watchdog
Timer
M
U
Postscaler
Postscaler
X
8 - to - 1 MUX
PS2:PS0
PSA
WDT Enable
Configuration Bit
To Timer0 (Figure 7-4)
1
0
PSA
MUX
Note: T0CS, T0SE, PSA, PS2:PS0
are bits in the OPTION register.
WDT
Time-out
TABLE 8-6:
Address
N/A
SUMMARY OF REGISTERS ASSOCIATED WITH THE WATCHDOG TIMER
Name
OPTION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1 Bit 0
GPWU
GPPU
T0CS
T0SE
PSA
PS2
PS1
PS0
Value on
Power-On
Reset
Value on
MCLR and
WDT Reset
Value on
Wake-up on
Pin Change
1111 1111
1111 1111
1111 1111
Legend: Shaded boxes = Not used by Watchdog Timer, — = unimplemented, read as '0', u = unchanged
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 37
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PIC12CE5XX
8.7
Time-Out Sequence, Power Down,
and Wake-up from SLEEP Status Bits
(TO/PD/GPWUF)
The TO, PD, and GPWUF bits in the STATUS register
can be tested to determine if a RESET condition has
been caused by a power-up condition, a MCLR or
Watchdog Timer (WDT) reset, or a MCLR or WDT
reset.
TABLE 8-7:
GPWUF TO
PD
0
0
0
0
1
0
1
0
0
1
1
0
u
u
1
1
0
Legend:
To reset PIC12CE5XX devices when a brown-out
occurs, external brown-out protection circuits may be
built, as shown in Figure 8-13 and Figure 8-14.
VDD
VDD
33k
10k
Event
GPWUF
TO
PD
0
1
1
0
0
u
SLEEP instruction
CLRWDT
instruction
Wake-up from
SLEEP on pin
change
u
1
0
u
1
1
1
1
0
MCLR
This circuit will activate reset when VDD goes below Vz +
0.7V (where Vz = Zener voltage).
*Refer to Figure 8-7 and Table 11-7 for internal weak pullup on MCLR.
FIGURE 8-14: BROWN-OUT PROTECTION
CIRCUIT 2
VDD
EVENTS AFFECTING TO/PD
STATUS BITS
Power-up
WDT Time-out
Q1
40k* PIC12CE5XX
These STATUS bits are only affected by events listed
in Table 8-8.
VDD
R1
Remarks
Q1
MCLR
R2
No effect
on PD
Legend: u = unchanged
A WDT time-out will occur regardless of the status of the
TO bit. A SLEEP instruction will be executed, regardless of
the status of the PD bit. Table 8-7 reflects the status of TO
and PD after the corresponding event.
Table 8-4 lists the reset conditions for the special
function registers, while Table 8-3 lists the reset
conditions for all the registers.
DS40172A-page 38
A brown-out is a condition where device power (VDD)
dips below its minimum value, but not to zero, and then
recovers. The device should be reset in the event of a
brown-out.
RESET caused by
WDT wake-up from
SLEEP
WDT time-out (not from
SLEEP)
MCLR wake-up from
SLEEP
Power-up
MCLR not during SLEEP
Wake-up from SLEEP on
pin change
Legend: u = unchanged
Note 1: The TO, PD, and GPWUF bits maintain their status (u) until a reset
occurs. A low-pulse on the MCLR
input does not change the TO, PD,
and GPWUF status bits.
TABLE 8-8:
Reset on Brown-Out
FIGURE 8-13: BROWN-OUT PROTECTION
CIRCUIT 1
TO/PD/GPWUF STATUS
AFTER RESET
0
8.8
40k
PIC12CE5XX
This brown-out circuit is less expensive, although
less accurate. Transistor Q1 turns off when VDD
is below a certain level such that:
VDD •
R1
R1 + R2
= 0.7V
*Refer to Figure 8-7 and Table 11-7 for internal weak
pull-up on MCLR.
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 39 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
8.9
Power-Down Mode (SLEEP)
8.10
A device may be powered down (SLEEP) and later
powered up (Wake-up from SLEEP).
8.9.1
SLEEP
The Power-Down mode is entered by executing a
SLEEP instruction.
If enabled, the Watchdog Timer will be cleared but
keeps running, the TO bit (STATUS<4>) is set, the PD
bit (STATUS<3>) is cleared and the oscillator driver is
turned off. The I/O ports maintain the status they had
before the SLEEP instruction was executed (driving
high, driving low, or hi-impedance).
It should be noted that a RESET generated by a WDT
time-out does not drive the MCLR pin low.
For lowest current consumption while powered down,
the T0CKI input should be at VDD or VSS and the GP3/
MCLR/VPP pin must be at a logic high level if MCLR is
enabled.
8.9.2
Program Verification/Code Protection
If the code protection bit has not been programmed,
the on-chip program memory can be read out for
verification purposes.
The first 64 locations can be read regardless of the
code protection bit setting.
Note:
8.11
The location containing the pre-programmed internal RC oscillator calibration
value is never code protected.
ID Locations
Four memory locations are designated as ID locations
where the user can store checksum or other codeidentification numbers. These locations are not
accessible during normal execution but are readable
and writable during program/verify.
Use only the lower 4 bits of the ID locations and
always program the upper 8 bits as '0's.
WAKE-UP FROM SLEEP
The device can wake-up from SLEEP through one of
the following events:
1.
2.
3.
An external reset input on GP3/MCLR/VPP pin,
when configured as MCLR.
A Watchdog Timer time-out reset (if WDT was
enabled).
A change on input pin GP0, GP1, or GP3/
MCLR/VPP when wake-up on change is
enabled.
These events cause a device reset. The TO, PD, and
GPWUF bits can be used to determine the cause of
device reset. The TO bit is cleared if a WDT time-out
occurred (and caused wake-up). The PD bit, which is
set on power-up, is cleared when SLEEP is invoked.
The GPWUF bit indicates a change in state while in
SLEEP at pins GP0, GP1, or GP3 (since the last time
there was a file or bit operation on GP port).
Caution: Right before entering SLEEP, read the
input pins. When in SLEEP, wake up
occurs when the values at the pins change
from the state they were in at the last
reading. If a wake-up on change occurs
and the pins are not read before
reentering SLEEP, a wake up will occur
immediately even if no pins change while
in SLEEP mode.
The WDT is cleared when the device wakes from
sleep, regardless of the wake-up source.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 39
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PIC12CE5XX
8.12
In-Circuit Serial Programming™
The PIC12CE5XX microcontrollers program memory
can be serially programmed while in the end application circuit. This is simply done with two lines for clock
and data, and three other lines for power, ground, and
the programming voltage. This allows customers to
manufacture boards with unprogrammed devices, and
then program the microcontroller just before shipping
the product. This also allows the most recent firmware
or a custom firmware to be programmed.
FIGURE 8-15: TYPICAL IN-CIRCUIT SERIAL
PROGRAMMING
CONNECTION
External
Connector
Signals
The device is placed into a program/verify mode by
holding the GP1 and GP0 pins low while raising the
MCLR (VPP) pin from VIL to VIHH (see programming
specification). GP1 becomes the programming clock
and GP0 becomes the programming data. Both GP1
and GP0 are Schmitt Trigger inputs in this mode.
After reset, a 6-bit command is then supplied to the
device. Depending on the command, 14-bits of program data are then supplied to or from the device,
depending if the command was a load or a read. For
complete details of serial programming, please refer to
the PIC12CE5XX Programming Specifications in the
In-Circuit Serial Programming Guide.
To Normal
Connections
PIC12CE5XX
+5V
VDD
0V
VSS
VPP
MCLR/VPP
CLK
GP1
Data I/O
GP0
VDD
To Normal
Connections
A typical in-circuit serial programming connection is
shown in Figure 8-15.
DS40172A-page 40
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 41 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
9.0
INSTRUCTION SET SUMMARY
Each PIC12CE5XX instruction is a 12-bit word divided
into an OPCODE, which specifies the instruction type,
and one or more operands which further specify the
operation of the instruction. The PIC12CE5XX
instruction set summary in Table 9-2 groups the
instructions into byte-oriented, bit-oriented, and literal
and control operations. Table 9-1 shows the opcode
field descriptions.
For byte-oriented instructions, 'f' represents a file
register designator and 'd' represents a destination
designator. The file register designator is used to
specify which one of the 32 file registers is to be used
by the instruction.
The destination designator specifies where the result
of the operation is to be placed. If 'd' is '0', the result is
placed in the W register. If 'd' is '1', the result is placed
in the file register specified in the instruction.
All instructions are executed within a single instruction
cycle, unless a conditional test is true or the program
counter is changed as a result of an instruction. In this
case, the execution takes 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.
Figure 9-1 shows the three general formats that the
instructions can have. All examples in the figure use the
following format to represent a hexadecimal number:
0xhhh
where 'h' signifies a hexadecimal digit.
FIGURE 9-1:
Byte-oriented file register operations
11
For bit-oriented instructions, 'b' represents a bit field
designator which selects the number of the bit affected
by the operation, while 'f' represents the number of the
file in which the bit is located.
For literal and control operations, 'k' represents an
8 or 9-bit constant or literal value.
TABLE 9-1:
OPCODE
Register file address (0x00 to 0x7F)
Working register (accumulator)
b
Bit address within an 8-bit file register
k
Literal field, constant data or label
x
Don't care location (= 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.
d
Destination select;
d = 0 (store result in W)
d = 1 (store result in file register 'f')
Default is d = 1
Top of Stack
PC
Program Counter
WDT
Watchdog Timer Counter
TO
Time-Out bit
PD
Power-Down bit
dest
[ ]
Options
Contents
→
Assigned to
<>
Register bit field
italics
8 7
5 4
b (BIT #)
f (FILE #)
0
Literal and control operations (except GOTO)
11
8
7
OPCODE
0
k (literal)
k = 8-bit immediate value
Literal and control operations - GOTO instruction
11
9
8
OPCODE
0
k (literal)
k = 9-bit immediate value
Destination, either the W register or the specified
register file location
( )
∈
0
f (FILE #)
b = 3-bit bit address
f = 5-bit file register address
W
Label name
4
Bit-oriented file register operations
11
f
TOS
5
d
d = 0 for destination W
d = 1 for destination f
f = 5-bit file register address
Description
label
6
OPCODE
OPCODE FIELD
DESCRIPTIONS
Field
GENERAL FORMAT FOR
INSTRUCTIONS
In the set of
User defined term (font is courier)
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 41
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PIC12CE5XX
TABLE 9-2:
INSTRUCTION SET SUMMARY
Mnemonic,
Operands
ADDWF
ANDWF
CLRF
CLRW
COMF
DECF
DECFSZ
INCF
INCFSZ
IORWF
MOVF
MOVWF
NOP
RLF
RRF
SUBWF
SWAPF
XORWF
f,d
f,d
f
–
f, d
f, d
f, d
f, d
f, d
f, d
f, d
f
–
f, d
f, d
f, d
f, d
f, d
12-Bit Opcode
Description
Cycles MSb
Add W and f
AND W with f
Clear f
Clear W
Complement f
Decrement f
Decrement f, Skip if 0
Increment f
Increment f, Skip if 0
Inclusive OR W with f
Move f
Move W to f
No Operation
Rotate left f through Carry
Rotate right f through Carry
Subtract W from f
Swap f
Exclusive OR W with f
LSb
Status
Affected Notes
1
1
1
1
1
1
1(2)
1
1(2)
1
1
1
1
1
1
1
1
1
0001
0001
0000
0000
0010
0000
0010
0010
0011
0001
0010
0000
0000
0011
0011
0000
0011
0001
11df
01df
011f
0100
01df
11df
11df
10df
11df
00df
00df
001f
0000
01df
00df
10df
10df
10df
ffff
ffff
ffff
0000
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
0000
ffff
ffff
ffff
ffff
ffff
C,DC,Z
Z
Z
Z
Z
Z
None
Z
None
Z
Z
None
None
C
C
C,DC,Z
None
Z
1,2,4
2,4
4
1
1
1 (2)
1 (2)
0100
0101
0110
0111
bbbf
bbbf
bbbf
bbbf
ffff
ffff
ffff
ffff
None
None
None
None
2,4
2,4
1
2
1
2
1
1
1
2
1
1
1
1110
1001
0000
101k
1101
1100
0000
1000
0000
0000
1111
kkkk
kkkk
0000
kkkk
kkkk
kkkk
0000
kkkk
0000
0000
kkkk
kkkk
kkkk
0100
kkkk
kkkk
kkkk
0010
kkkk
0011
0fff
kkkk
Z
None
TO, PD
None
Z
None
None
None
TO, PD
None
Z
2,4
2,4
2,4
2,4
2,4
2,4
1,4
2,4
2,4
1,2,4
2,4
2,4
BIT-ORIENTED FILE REGISTER OPERATIONS
BCF
BSF
BTFSC
BTFSS
f, b
f, b
f, b
f, b
Bit Clear f
Bit Set f
Bit Test f, Skip if Clear
Bit Test f, Skip if Set
LITERAL AND CONTROL OPERATIONS
ANDLW
CALL
CLRWDT
GOTO
IORLW
MOVLW
OPTION
RETLW
SLEEP
TRIS
XORLW
k
k
k
k
k
k
–
k
–
f
k
AND literal with W
Call subroutine
Clear Watchdog Timer
Unconditional branch
Inclusive OR Literal with W
Move Literal to W
Load OPTION register
Return, place Literal in W
Go into standby mode
Load TRIS register
Exclusive OR Literal to W
1
3
Note 1: The 9th bit of the program counter will be forced to a '0' by any instruction that writes to the PC except for GOTO.
(Section 4-5)
2: When an I/O register is modified as a function of itself (e.g. MOVF GPIO, 1), 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'.
3: The instruction TRIS f, where f = 6 causes the contents of the W register to be written to the tristate latches of
GPIO. A '1' forces the pin to a hi-impedance state and disables the output buffers.
4: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared
(if assigned to TMR0).
DS40172A-page 42
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 43 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
ADDWF
Add W and f
Syntax:
[ label ] ADDWF
ANDWF
AND W with f
Syntax:
Operands:
[ label ] ANDWF
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(W) + (f) → (dest)
Operation:
(W) .AND. (f) → (dest)
f,d
Status Affected: C, DC, Z
Encoding:
0001
Description:
Status Affected: Z
11df
Encoding:
ffff
0001
Add the contents of the W register and
register 'f'. If 'd' is 0 the result is stored
in the W register. If 'd' is '1' the result is
stored back in register 'f'.
Description:
Words:
1
Words:
1
Cycles:
1
Cycles:
1
Example:
ADDWF
Example:
ANDWF
FSR, 0
Before Instruction
W
=
FSR =
01df
FSR,
W =
FSR =
0x17
0xC2
After Instruction
W
=
FSR =
W
=
FSR =
0xD9
0xC2
ANDLW
And literal with W
Syntax:
[ label ] ANDLW
Operands:
0 ≤ k ≤ 255
Operation:
(W).AND. (k) → (W)
0x17
0x02
BCF
Bit Clear f
Syntax:
[ label ] BCF
Operands:
0 ≤ f ≤ 31
0≤b≤7
Status Affected: Z
Operation:
0 → (f<b>)
Encoding:
Status Affected: None
kkkk
k
kkkk
The contents of the W register are
AND’ed with the eight-bit literal 'k'. The
result is placed in the W register.
Words:
1
Cycles:
1
Example:
ANDLW
Encoding:
Description:
=
1
Cycles:
1
Example:
BCF
0x5F
=
bbbf
ffff
FLAG_REG,
7
Before Instruction
FLAG_REG = 0xC7
0xA3
After Instruction
After Instruction
W
0100
f,b
Bit 'b' in register 'f' is cleared.
Words:
Before Instruction
W
1
Before Instruction
0x17
0xC2
1110
ffff
The contents of the W register are
AND’ed with register 'f'. If 'd' is 0 the
result is stored in the W register. If 'd' is
'1' the result is stored back in register 'f'.
After Instruction
Description:
f,d
FLAG_REG = 0x47
0x03
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 43
12CF5XX_GEBook Page 44 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
BSF
Bit Set f
Syntax:
[ label ] BSF
BTFSS
Bit Test f, Skip if Set
Syntax:
Operands:
[ label ] BTFSS f,b
0 ≤ f ≤ 31
0≤b≤7
Operands:
0 ≤ f ≤ 31
0≤b<7
Operation:
1 → (f<b>)
Operation:
skip if (f<b>) = 1
f,b
Status Affected: None
Encoding:
Status Affected: None
0101
bbbf
Encoding:
ffff
Description:
Bit 'b' in register 'f' is set.
Words:
1
Cycles:
1
Example:
BSF
FLAG_REG,
Description:
7
Before Instruction
FLAG_REG = 0x0A
After Instruction
FLAG_REG = 0x8A
0111
Words:
1
Cycles:
1(2)
Example:
HERE
FALSE
TRUE
BTFSC
Bit Test f, Skip if Clear
Syntax:
[ label ] BTFSC f,b
Operands:
0 ≤ f ≤ 31
0≤b≤7
Before Instruction
skip if (f<b>) = 0
After Instruction
Operation:
•
•
PC
Status Affected: None
Encoding:
Description:
0110
bbbf
bbbf
ffff
If bit 'b' in register 'f' is 0 then the next
instruction is skipped.
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 an NOP is
executed instead, making this a 2 cycle
instruction.
If FLAG<1>
PC
if FLAG<1>
PC
BTFSS
GOTO
•
FLAG,1
PROCESS_CODE
=
address (HERE)
=
=
=
=
0,
address (FALSE);
1,
address (TRUE)
If bit 'b' is 0 then the next instruction
fetched during the current instruction
execution is discarded, and an NOP is
executed instead, making this a 2 cycle
instruction.
Words:
1
Cycles:
1(2)
Example:
HERE
FALSE
TRUE
BTFSC
GOTO
FLAG,1
PROCESS_CODE
•
•
•
Before Instruction
PC
=
address (HERE)
=
=
=
=
0,
address (TRUE);
1,
address(FALSE)
After Instruction
if FLAG<1>
PC
if FLAG<1>
PC
DS40172A-page 44
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 45 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
CALL
Subroutine Call
CLRW
Syntax:
[ label ] CALL k
Syntax:
[ label ] CLRW
Operands:
0 ≤ k ≤ 255
Operands:
None
Operation:
(PC) + 1→ Top of Stack;
k → PC<7:0>;
(STATUS<6:5>) → PC<10:9>;
0 → PC<8>
Operation:
00h → (W);
1→Z
Status Affected: Z
Encoding:
Status Affected: None
Encoding:
Description:
1001
kkkk
kkkk
Cycles:
2
Example:
Words:
1
Cycles:
1
Example:
CLRW
HERE
CALL
W
address (HERE)
address (THERE)
address (HERE + 1)
CLRF
Clear f
Syntax:
[ label ] CLRF
Operands:
0 ≤ f ≤ 31
Operation:
00h → (f);
1→Z
f
0000
1
1
Example:
CLRF
Clear Watchdog Timer
[ label ] CLRWDT
Operands:
None
Operation:
00h → WDT;
0 → WDT prescaler (if assigned);
1 → TO;
1 → PD
Encoding:
Description:
011f
ffff
1
Cycles:
1
Example:
0x5A
=
=
0x00
1
 1997 Microchip Technology Inc.
0000
0100
CLRWDT
Before Instruction
FLAG_REG
=
0000
The CLRWDT instruction resets the
WDT. It also resets the prescaler, if the
prescaler is assigned to the WDT and
not Timer0. Status bits TO and PD are
set.
Words:
WDT counter =
?
After Instruction
WDT counter
WDT prescale
TO
PD
After Instruction
FLAG_REG
Z
0x00
1
Syntax:
Before Instruction
FLAG_REG
=
=
Status Affected: TO, PD
The contents of register 'f' are cleared
and the Z bit is set.
Cycles:
0x5A
CLRWDT
Status Affected: Z
Words:
=
THERE
After Instruction
Description:
0000
Before Instruction
W
Z
Before Instruction
Encoding:
0100
The W register is cleared. Zero bit (Z)
is set.
After Instruction
1
PC =
TOS =
0000
Description:
Subroutine call. First, return address
(PC+1) is pushed onto the stack. The
eight bit immediate address is loaded
into PC bits <7:0>. The upper bits
PC<10:9> are loaded from STATUS<6:5>, PC<8> is cleared. CALL is a
two cycle instruction.
Words:
PC =
Clear W
Preliminary
=
=
=
=
0x00
0
1
1
DS40172A-page 45
12CF5XX_GEBook Page 46 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
COMF
Complement f
Syntax:
[ label ] COMF
DECFSZ
Decrement f, Skip if 0
Syntax:
[ label ] DECFSZ f,d
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(f) → (dest)
Operation:
(f) – 1 → d;
f,d
Status Affected: Z
Encoding:
0010
01df
Encoding:
ffff
Description:
The contents of register 'f' are complemented. If 'd' is 0 the result is stored in
the W register. If 'd' is 1 the result is
stored back in register 'f'.
Words:
1
Cycles:
1
Example:
COMF
=
0x13
After Instruction
REG1
W
=
=
Description:
REG1,0
Before Instruction
REG1
Decrement f
Syntax:
[ label ] DECF f,d
0 ≤ f ≤ 31
d ∈ [0,1]
1
Cycles:
1(2)
Example:
HERE
Operation:
(f) – 1 → (dest)
PC
CNT
if CNT
PC
if CNT
PC
1
Cycles:
1
Example:
DECF
Before Instruction
CNT
Z
=
=
=
=
DECFSZ
GOTO
CONTINUE •
•
•
CNT, 1
LOOP
=
address (HERE)
CNT,
=
=
=
≠
=
CNT - 1;
0,
address (CONTINUE);
0,
address (HERE+1)
ffff
GOTO
Unconditional Branch
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 511
Operation:
k → PC<8:0>;
STATUS<6:5> → PC<10:9>
1
GOTO k
Status Affected: None
0x01
0
Encoding:
Description:
After Instruction
CNT
Z
11df
Decrement register 'f'. If 'd' is 0 the
result is stored in the W register. If 'd' is
1 the result is stored back in register 'f'.
Words:
ffff
Before Instruction
Status Affected: Z
0000
11df
After Instruction
Operands:
Encoding:
0010
The contents of register 'f' are decremented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
If the result is 0, the next instruction,
which is already fetched, is discarded
and an NOP is executed instead making it a two cycle instruction.
Words:
0x13
0xEC
DECF
Description:
skip if result = 0
Status Affected: None
0x00
1
101k
kkkk
kkkk
GOTO is an unconditional branch. The
9-bit immediate value is loaded into PC
bits <8:0>. The upper bits of PC are
loaded from STATUS<6:5>. GOTO is a
two cycle instruction.
Words:
1
Cycles:
2
Example:
GOTO THERE
After Instruction
PC =
DS40172A-page 46
Preliminary
address (THERE)
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 47 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
INCF
Increment f
IORLW
Inclusive OR literal with W
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ k ≤ 255
Operation:
(f) + 1 → (dest)
(W) .OR. (k) → (W)
Operation:
INCF f,d
Status Affected: Z
Status Affected: Z
Encoding:
Description:
10df
ffff
1
Cycles:
1
INCF
CNT,
=
=
kkkk
kkkk
The contents of the W register are
OR’ed with the eight bit literal 'k'. The
result is placed in the W register.
Words:
1
Cycles:
1
Example:
IORLW
0x35
Before Instruction
1
W
Before Instruction
CNT
Z
1101
Description:
The contents of register 'f' are incremented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
Words:
Example:
Encoding:
0010
IORLW k
=
0x9A
After Instruction
0xFF
0
W
Z
=
=
0xBF
0
After Instruction
CNT
Z
=
=
0x00
1
INCFSZ
Increment f, Skip if 0
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
0011
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(W).OR. (f) → (dest)
IORWF
f,d
Status Affected: Z
Encoding:
Status Affected: None
Description:
Inclusive OR W with f
Syntax:
INCFSZ f,d
(f) + 1 → (dest), skip if result = 0
Encoding:
IORWF
11df
00df
ffff
Inclusive OR the W register with register 'f'. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
Words:
1
Cycles:
1
Example:
IORWF
ffff
The contents of register 'f' are incremented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
If the result is 0, then the next instruction, which is already fetched, is discarded and an NOP is executed
instead making it a two cycle instruction.
0001
Description:
RESULT, 0
Before Instruction
RESULT =
W
=
0x13
0x91
After Instruction
Words:
1
Cycles:
1(2)
Example:
HERE
INCFSZ
GOTO
CONTINUE •
•
•
CNT,
LOOP
1
RESULT =
W
=
Z
=
0x13
0x93
0
Before Instruction
PC
=
address (HERE)
After Instruction
CNT
if CNT
PC
if CNT
PC
=
=
=
≠
=
CNT + 1;
0,
address (CONTINUE);
0,
address (HERE +1)
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 47
12CF5XX_GEBook Page 48 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
MOVF
Move f
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(f) → (dest)
MOVF f,d
0010
Description:
Move W to f
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
Operation:
(W) → (f)
Encoding:
00df
ffff
Description:
The contents of register 'f' is moved to
destination 'd'. If 'd' is 0, destination is
the W register. If 'd' is 1, the destination
is file register 'f'. 'd' is 1 is useful to test
a file register since status flag Z is
affected.
1
Cycles:
1
Example:
0000
001f
MOVF
1
Cycles:
1
Example:
MOVWF
TEMP_REG
W
FSR,
TEMP_REG
=
=
0xFF
0x4F
=
=
0x4F
0x4F
After Instruction
0
TEMP_REG
W
value in FSR register
NOP
No Operation
MOVLW
Move Literal to W
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
None
Operands:
0 ≤ k ≤ 255
Operation:
No operation
Operation:
k → (W)
Status Affected: None
MOVLW k
Status Affected: None
Encoding:
ffff
Move data from the W register to register 'f'.
Words:
After Instruction
=
f
Before Instruction
Words:
W
MOVWF
Status Affected: None
Status Affected: Z
Encoding:
MOVWF
1100
Encoding:
kkkk
kkkk
0000
NOP
0000
Description:
No operation.
1
Description:
The eight bit literal 'k' is loaded into the
W register. The don’t cares will assemble as 0s.
Words:
Cycles:
1
Words:
1
Example:
NOP
Cycles:
1
Example:
MOVLW
0000
0x5A
After Instruction
W
=
DS40172A-page 48
0x5A
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 49 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
OPTION
Load OPTION Register
RLF
Rotate Left f through Carry
Syntax:
[ label ]
Syntax:
[ label ] RLF
Operands:
None
Operands:
Operation:
(W) → OPTION
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
See description below
OPTION
Status Affected: None
Encoding:
0000
Description:
0000
0010
Status Affected: C
The content of the W register is loaded
into the OPTION register.
Words:
1
Cycles:
1
Example
Encoding:
Description:
OPTION
0011
=
0x07
RETLW
Return with Literal in W
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operation:
k → (W);
TOS → PC
Words:
1
Cycles:
1
Example:
RLF
Encoding:
1000
RETLW k
kkkk
REG1
C
REG1
W
C
1
Cycles:
2
Example:
CALL TABLE ;W contains
;table offset
;value.
•
;W now has table
•
;value.
•
ADDWF PC
;W = offset
RETLW k1
;Begin table
RETLW k2
;
•
•
•
RETLW kn
; End of table
W
=
=
=
=
=
1110 0110
1100 1100
1
RRF
Rotate Right f through Carry
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
See description below
RRF f,d
Status Affected: C
Encoding:
Description:
0011
00df
ffff
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 the
W register. If 'd' is 1 the result is placed
back in register 'f'.
C
Words:
1
Cycles:
1
Example:
RRF
register 'f'
REG1,0
Before Instruction
0x07
REG1
C
After Instruction
W
1110 0110
0
kkkk
Words:
Before Instruction
=
=
After Instruction
The W register is loaded with the eight
bit literal 'k'. The program counter is
loaded from the top of the stack (the
return address). This is a two cycle
instruction.
TABLE
REG1,0
Before Instruction
Status Affected: None
Description:
ffff
register 'f'
C
0x07
After Instruction
OPTION =
01df
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 the
W register. If 'd' is 1 the result is stored
back in register 'f'.
Before Instruction
W
f,d
value of k8
=
=
1110 0110
0
After Instruction
REG1
W
C
 1997 Microchip Technology Inc.
Preliminary
=
=
=
1110 0110
0111 0011
0
DS40172A-page 49
12CF5XX_GEBook Page 50 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
SLEEP
Enter SLEEP Mode
SUBWF
Subtract W from f
Syntax:
[label]
Syntax:
[label]
Operands:
None
Operands:
Operation:
00h → WDT;
0 → WDT prescaler;
1 → TO;
0 → PD
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(f) – (W) → (dest)
SLEEP
Status Affected: C, DC, Z
Encoding:
Status Affected: TO, PD, GPWUF
Encoding:
Description:
0000
0000
Description:
0011
Time-out status bit (TO) is set. The
power down status bit (PD) is cleared.
GPWUF is unaffected.
The WDT and its prescaler are
cleared.
The processor is put into SLEEP mode
with the oscillator stopped. See section on SLEEP for more details.
Words:
1
Cycles:
1
Example:
SLEEP
SUBWF f,d
0000
10df
ffff
Subtract (2’s complement method) the
W register from register 'f'. If 'd' is 0 the
result is stored in the W register. If 'd' is
1 the result is stored back in register 'f'.
Words:
1
Cycles:
1
Example 1:
SUBWF
REG1, 1
Before Instruction
REG1
W
C
=
=
=
3
2
?
After Instruction
REG1
W
C
=
=
=
1
2
1
; result is positive
Example 2:
Before Instruction
REG1
W
C
=
=
=
2
2
?
After Instruction
REG1
W
C
=
=
=
0
2
1
; result is zero
Example 3:
Before Instruction
REG1
W
C
=
=
=
1
2
?
After Instruction
REG1
W
C
DS40172A-page 50
Preliminary
=
=
=
FF
2
0
; result is negative
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 51 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
SWAPF
Swap Nibbles in f
XORLW
Exclusive OR literal with W
Syntax:
[ label ] SWAPF f,d
Syntax:
[label]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ k ≤ 255
(f<3:0>) → (dest<7:4>);
(f<7:4>) → (dest<3:0>)
Operation:
Operation:
(W) .XOR. k → (W)
Status Affected: Z
Encoding:
Status Affected: None
Encoding:
0011
Description:
10df
1111
Description:
ffff
kkkk
kkkk
The contents of the W register are
XOR’ed with the eight bit literal 'k'. The
result is placed in the W register.
The upper and lower nibbles of register
'f' are exchanged. If 'd' is 0 the result is
placed in W register. If 'd' is 1 the result
is placed in register 'f'.
Words:
1
Cycles:
1
Words:
1
Example:
XORLW
Cycles:
1
Example
SWAPF
0xAF
Before Instruction
REG1,
W
0
=
=
0xB5
After Instruction
Before Instruction
REG1
XORLW k
W
0xA5
=
0x1A
After Instruction
REG1
W
TRIS
=
=
0xA5
0X5A
XORWF
Exclusive OR W with f
Syntax:
[ label ] XORWF
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(W) .XOR. (f) → (dest)
Load TRIS Register
Syntax:
[ label ] TRIS
Operands:
f=6
Operation:
(W) → TRIS register f
f
Status Affected: Z
Encoding:
Status Affected: None
Encoding:
0000
Description:
Description:
0000
0fff
TRIS register 'f' (f = 6) is loaded with the
contents of the W register
0001
1
Words:
1
Cycles:
1
Cycles:
1
Example
XORWF
TRIS
GPIO
Before Instruction
W
=
TRIS
=
ffff
REG,1
Before Instruction
0XA5
REG
W
After Instruction
Note:
10df
Exclusive OR the contents of the W
register with register 'f'. If 'd' is 0 the
result is stored in the W register. If 'd' is
1 the result is stored back in register 'f'.
Words:
Example
f,d
0xAF
0xB5
After Instruction
0XA5
REG
W
f = 6 for PIC12C5XX only.
 1997 Microchip Technology Inc.
=
=
Preliminary
=
=
0x1A
0xB5
DS40172A-page 51
12CF5XX_GEBook Page 52 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
NOTES:
DS40172A-page 52
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 53 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
10.0
DEVELOPMENT SUPPORT
10.1
Development Tools
10.3
The PICmicrο microcontrollers are supported with a
full range of hardware and software development tools:
• PICMASTER/PICMASTER CE Real-Time
In-Circuit Emulator
• ICEPIC Low-Cost PIC16C5X and PIC16CXXX
In-Circuit Emulator
• PRO MATE II Universal Programmer
• PICSTART Plus Entry-Level Prototype
Programmer
• PICDEM-1 Low-Cost Demonstration Board
• PICDEM-2 Low-Cost Demonstration Board
• PICDEM-3 Low-Cost Demonstration Board
• MPASM Assembler
• MPLAB SIM Software Simulator
• MPLAB-C (C Compiler)
• Fuzzy Logic Development System
(fuzzyTECH−MP)
10.2
ICEPIC: Low-Cost PICmicro™
In-Circuit Emulator
ICEPIC is a low-cost in-circuit emulator solution for the
Microchip PIC12CXXX, PIC16C5X and PIC16CXXX
families of 8-bit OTP microcontrollers.
ICEPIC is designed to operate on PC-compatible
machines ranging from 286-AT through Pentium
based machines under Windows 3.x environment.
ICEPIC features real time, non-intrusive emulation.
10.4
PRO MATE II: Universal Programmer
The PRO MATE II Universal Programmer is a full-featured programmer capable of operating in stand-alone
mode as well as PC-hosted mode.
The PRO MATE II has programmable VDD and VPP
supplies which allows it to verify programmed memory
at VDD min and VDD max for maximum reliability. It has
an LCD display for displaying error messages, keys to
enter commands and a modular detachable socket
assembly to support various package types. In standalone mode the PRO MATE II can read, verify or program
PIC12CXXX,
PIC14C000,
PIC16C5X,
PIC16CXXX and PIC17CXX devices. It can also set
configuration and code-protect bits in this mode.
PICMASTER: High Performance
Universal In-Circuit Emulator with
MPLAB IDE
The PICMASTER Universal In-Circuit Emulator is
intended to provide the product development engineer
with a complete microcontroller design tool set for all
microcontrollers in the PIC12CXXX, PIC14C000,
PIC16C5X, PIC16CXXX and PIC17CXX families.
PICMASTER is supplied with the MPLAB Integrated
Development Environment (IDE), which allows editing,
“make” and download, and source debugging from a
single environment.
Interchangeable target probes allow the system to be
easily reconfigured for emulation of different processors. The universal architecture of the PICMASTER
allows expansion to support all new Microchip microcontrollers.
10.5
PICSTART Plus Entry Level
Development System
The PICSTART programmer is an easy-to-use, lowcost prototype programmer. It connects to the PC via
one of the COM (RS-232) ports. MPLAB Integrated
Development Environment software makes using the
programmer simple and efficient. PICSTART Plus is
not recommended for production programming.
PICSTART Plus supports all PIC12CXXX, PIC14C000,
PIC16C5X, PIC16CXXX and PIC17CXX devices with
up to 40 pins. Larger pin count devices such as the
PIC16C923 and PIC16C924 may be supported with an
adapter socket.
The PICMASTER 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 compatible 386
(and higher) machine platform and Microsoft Windows
3.x environment were chosen to best make these features available to you, the end user.
A CE compliant version of PICMASTER is available for
European Union (EU) countries.
 1997 Microchip Technology Inc.
Preliminary
DS40172A - page 53
12CF5XX_GEBook Page 54 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
10.6
PICDEM-1 Low-Cost PICmicro
Demonstration Board
The PICDEM-1 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 users can
program the sample microcontrollers provided with
the PICDEM-1 board, on a PRO MATE II or
PICSTART-Plus programmer, and easily test firmware. The user can also connect the PICDEM-1
board to the PICMASTER emulator and download
the firmware to the emulator for testing. Additional 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.
10.7
PICDEM-2 Low-Cost PIC16CXX
Demonstration Board
The PICDEM-2 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 board, on a PRO MATE II programmer or PICSTART-Plus, and easily test firmware.
The PICMASTER emulator may also be used with the
PICDEM-2 board to test firmware. Additional 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 I2C bus and separate headers for connection to an LCD module and a keypad.
10.8
PICDEM-3 Low-Cost PIC16CXXX
Demonstration Board
The PICDEM-3 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 a 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 board, on a PRO MATE II programmer or PICSTART Plus with an adapter socket, and
easily test firmware. The PICMASTER emulator may
also be used with the PICDEM-3 board to test firmware. Additional prototype area has been provided to
the user for adding hardware and connecting it to the
microcontroller socket(s). Some of the features include
DS40172A - page 54
an 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
board is an LCD panel, with 4 commons and 12 segments, that is capable of displaying time, temperature
and day of the week. The PICDEM-3 provides an additional RS-232 interface and Windows 3.1 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.
10.9
MPLAB™ Integrated Development
Environment Software
The MPLAB IDE Software brings an ease of software
development previously unseen in the 8-bit microcontroller market. MPLAB is a windows based application
which contains:
• A full featured editor
• Three operating modes
- editor
- emulator
- simulator
• A project manager
• Customizable tool bar and key mapping
• A status bar with project information
• Extensive on-line help
MPLAB allows you to:
• Edit your source files (either assembly or ‘C’)
• One touch assemble (or compile) and download
to PICmicro tools (automatically updates all
project information)
• Debug using:
- source files
- absolute listing file
• Transfer data dynamically via DDE (soon to be
replaced by OLE)
• Run up to four emulators on the same PC
The ability to use MPLAB with Microchip’s simulator
allows a consistent platform and the ability to easily
switch from the low cost simulator to the full featured
emulator with minimal retraining due to development
tools.
10.10
Assembler (MPASM)
The MPASM Universal Macro Assembler is a PChosted symbolic assembler. It supports all microcontroller series including the PIC12C5XX, PIC14000,
PIC16C5X, PIC16CXXX, and PIC17CXX families.
MPASM offers full featured Macro capabilities, conditional assembly, and several source and listing formats.
It generates various object code formats to support
Microchip's development tools as well as third party
programmers.
MPASM allows full symbolic debugging from
PICMASTER, Microchip’s Universal Emulator System.
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 55 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
MPASM has the following features to assist in developing software for specific use applications.
• Provides translation of Assembler source code to
object code for all Microchip microcontrollers.
• Macro assembly capability.
• Produces all the files (Object, Listing, Symbol,
and special) required for symbolic debug with
Microchip’s emulator systems.
• Supports Hex (default), Decimal and Octal source
and listing formats.
MPASM provides a rich directive language to support
programming of the PICmicro. Directives are helpful in
making the development of your assemble source code
shorter and more maintainable.
10.11
Software Simulator (MPLAB-SIM)
The MPLAB-SIM Software Simulator allows code
development in a PC host environment. It allows the
user to simulate the PICmicro series microcontrollers
on an instruction level. On any given instruction, the
user may examine or modify any of the data areas or
provide external stimulus to any of the pins. The input/
output radix can be set by the user and the execution
can be performed in; single step, execute until break, or
in a trace mode.
MPLAB-SIM fully supports symbolic debugging using
MPLAB-C and MPASM. The Software Simulator offers
the low cost flexibility to develop and debug code outside of the laboratory environment making it an excellent multi-project software development tool.
10.12
C Compiler (MPLAB-C)
10.14
MP-DriveWay – Application Code
Generator
MP-DriveWay is an easy-to-use Windows-based Application Code Generator. With MP-DriveWay you can
visually configure all the peripherals in a PICmicro
device and, with a click of the mouse, generate all the
initialization and many functional code modules in C
language. The output is fully compatible with Microchip’s MPLAB-C C compiler. The code produced is
highly modular and allows easy integration of your own
code. MP-DriveWay is intelligent enough to maintain
your code through subsequent code generation.
10.15
SEEVAL Evaluation and
Programming System
The SEEVAL SEEPROM Designer’s Kit supports all
Microchip 2-wire and 3-wire Serial EEPROMs. The kit
includes everything necessary to read, write, erase or
program special features of any Microchip SEEPROM
product including Smart Serials and secure serials.
The Total Endurance Disk is included to aid in tradeoff analysis and reliability calculations. The total kit can
significantly reduce time-to-market and result in an
optimized system.
10.16
KEELOQ Evaluation and
Programming Tools
KEELOQ evaluation and programming tools support
Microchips HCS Secure Data Products. The HCS evaluation kit includes an LCD display to show changing
codes, a decoder to decode transmissions, and a programming interface to program test transmitters.
The MPLAB-C Code Development System is a
complete ‘C’ compiler and integrated development
environment for Microchip’s PICmicro™ family of
microcontrollers. The compiler provides powerful integration capabilities and ease of use not found with
other compilers.
For easier source level debugging, the compiler provides symbol information that is compatible with the
MPLAB IDE memory display.
10.13
Fuzzy Logic Development System
(fuzzyTECH-MP)
fuzzyTECH-MP fuzzy logic development tool is available in two versions - a low cost introductory version,
MP Explorer, for designers to gain a comprehensive
working knowledge of fuzzy logic system design; and a
full-featured version, fuzzyTECH-MP, edition for implementing more complex systems.
Both versions include Microchip’s fuzzyLAB demonstration board for hands-on experience with fuzzy logic
systems implementation.
 1997 Microchip Technology Inc.
Preliminary
DS40172A - page 55
Emulator Products
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
PIC17C75X
✔
✔
✔
MPLAB
Integrated
Development
Environment
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
MPLAB C
Compiler
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
fuzzyTECH-MP
Explorer/Edition
Fuzzy Logic
Dev. Tool
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
MP-DriveWay
Applications
Code Generator
24CXX
25CXX
93CXX
✔
PICSTART
Lite Ultra Low-Cost
Dev. Kit
✔
✔
✔
✔
PRO MATE II
Universal
Programmer
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
KEELOQ
Programmer
PICDEM-2
PICDEM-3
KEELOQ
Evaluation Kit
✔
✔
SEEVAL
Designers Kit
Demo Boards
 1997 Microchip Technology Inc.
PICSTART
Plus Low-Cost
Universal Dev. Kit
PICDEM-1
HCS200
HCS300
HCS301
✔
Total Endurance
Software Model
Programmers
Preliminary
Software Tools
✔
✔
PIC16C6X PIC16C7XX PIC16C8X PIC16C9XX PIC17C4X
✔
✔
✔
✔
✔
✔
✔
✔
✔
12CF5XX_GEBook Page 56 Tuesday, October 21, 1997 8:23 AM
PIC16CXXX
PIC12CE5XX
PIC16C5X
DEVELOPMENT TOOLS FROM MICROCHIP
ICEPIC Low-Cost
In-Circuit Emulator
PIC14000
TABLE 10-1:
DS40172A - page 56
PICMASTER/
PICMASTER-CE
In-Circuit Emulator
PIC12CXXX
12CF5XX_GEBook Page 57 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
11.0
ELECTRICAL CHARACTERISTICS - PIC12CE5XX
Absolute Maximum Ratings†
Ambient Temperature under bias ........................................................................................................... –40˚C to +125˚C
Storage Temperature.............................................................................................................................. –65˚C to +150˚C
Voltage on VDD with respect to VSS .................................................................................................................0 to +7.0 V
Voltage on MCLR with respect to VSS...............................................................................................................0 to +14 V
Voltage on all other pins with respect to VSS ................................................................................–0.6 V to (VDD + 0.6 V)
Total Power Dissipation(1) ....................................................................................................................................700 mW
Max. Current out of VSS pin...................................................................................................................................200 mA
Max. Current into VDD pin......................................................................................................................................150 mA
Input Clamp Current, IIK (VI < 0 or VI > VDD) ....................................................................................................................±20 mA
Output Clamp Current, IOK (VO < 0 or VO > VDD) ............................................................................................................±20 mA
Max. Output Current sunk by any I/O pin ................................................................................................................25 mA
Max. Output Current sourced by any I/O pin...........................................................................................................25 mA
Max. Output Current sourced by I/O port (GPIO)..................................................................................................100 mA
Max. Output Current sunk by I/O port (GPIO )......................................................................................................100 mA
Note 1: Power Dissipation is calculated as follows: PDIS = VDD x {IDD - ∑ IOH} + ∑ {(VDD-VOH) x IOH} + ∑(VOL x IOL)
†NOTICE:
Stresses above those listed under "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.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 57
12CF5XX_GEBook Page 58 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
11.1
DC CHARACTERISTICS:
Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial)
–40°C ≤ TA ≤ +85°C (industrial)
–40°C ≤ TA ≤ +125°C (extended)
DC Characteristics
Power Supply Pins
Characteristic
Supply Voltage
PIC12CE518/519 (Commercial)
PIC12CE518/519 (Industrial)
PIC12CE518/519 (Extended)
Sym
Min
VDD
Typ(1)
Max
Units
Conditions
3.0
5.5
V
4.5
5.5
V
FOSC = DC to 4 MHz (Commercial/
Industrial)
FOSC = DC to 4 MHz (Extended)
RAM Data Retention
Voltage(2)
VDR
1.5*
V
Device in SLEEP mode
VDD Start Voltage to ensure
Power-on Reset
VPOR
VSS
V
See section on Power-on Reset for details
VDD Rise Rate to ensure
Power-on Reset
SVDD
0.05*
V/ms
See section on Power-on Reset for details
Supply Current(3)
No read/write to EEPROM
peripheral
IDD
—
1.8
2.4
mA
—
1.8
2.4
mA
—
15
27
µA
—
19
35
µA
—
19
35
µA
XT and EXTRC options (Note 4)
FOSC = 4 MHz, VDD = 5.5V
INTRC Option
FOSC = 4 MHz, VDD = 5.5V
LP OPTION, Commercial Temperature
FOSC = 32 kHz, VDD = 3.0V, WDT disabled
LP OPTION, Industrial Temperature
FOSC = 32 kHz, VDD = 3.0V, WDT disabled
LP OPTION, Extended Temperature
FOSC = 32 kHz, VDD = 4.5V, WDT disabled
—
1.9
2.6
mA
—
1.9
2.6
mA
Supply Current(3)
During read/write to
EEPROM peripheral
IDD
XT and EXTRC options (Note 4)
FOSC = 4 MHz, VDD = 5.5V,
SCL = 400 kHz
INTRC Option
FOSC = 4 MHz, VDD = 5.5V
SCL = 400 kHz
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is based on characterization results at 25°C. This data is for design guidance only and is not tested.
2: This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data.
3: The supply current is mainly a function of the operating voltage and frequency. Other factors such as bus
loading, oscillator type, bus rate, internal code execution pattern, and temperature also have an impact on
the current consumption.
a) The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tristated, pulled to
Vss, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified.
b) For standby current measurements, the conditions are the same, except that
the device is in SLEEP mode.
c) EEPROM data memory in standby unless otherwise indicated.
4: Does not include current through Rext. The current through the resistor can be estimated by the
formula: IR = VDD/2Rext (mA) with Rext in kOhm.
5: 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. EEPROM
data memory in standby.
DS40172A-page 58
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 59 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial)
–40°C ≤ TA ≤ +85°C (industrial)
–40°C ≤ TA ≤ +125°C (extended)
DC Characteristics
Power Supply Pins
Characteristic
Power-Down Current
WDT Enabled
Sym
(5)
WDT Disabled
Min
Typ(1)
Max
Units
—
—
—
—
—
—
4
4
5
0.26
0.26
2
13
14
23
5
6
13
µA
µA
µA
µA
µA
µA
Conditions
IPD
VDD = 3.0V, Commercial
VDD = 3.0V, Industrial
VDD = 4.5V, Extended
VDD = 3.0V, Commercial
VDD = 3.0V, Industrial
VDD = 4.5V, Extended
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is based on characterization results at 25°C. This data is for design guidance only and is not tested.
2: This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data.
3: The supply current is mainly a function of the operating voltage and frequency. Other factors such as bus
loading, oscillator type, bus rate, internal code execution pattern, and temperature also have an impact on
the current consumption.
a) The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tristated, pulled to
Vss, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified.
b) For standby current measurements, the conditions are the same, except that
the device is in SLEEP mode.
c) EEPROM data memory in standby unless otherwise indicated.
4: Does not include current through Rext. The current through the resistor can be estimated by the
formula: IR = VDD/2Rext (mA) with Rext in kOhm.
5: 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. EEPROM
data memory in standby.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 59
12CF5XX_GEBook Page 60 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
11.2
DC CHARACTERISTICS:
Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial)
–40°C ≤ TA ≤ +85°C (industrial)
–40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in Section 11.1.
DC Characteristics
All Pins Except
Power Supply Pins
Characteristic
Input Low Voltage
I/O ports
Sym
Min
Typ(1)
Max
Units
VSS
0.8
V
VSS
0.15 VDD
V
VSS
VSS
VSS
0.15 VDD
0.15 VDD
0.3 VDD
V
V
V
0.25VDD+0.8V
2.0
0.2VDD+1V
0.85 VDD
0.85 VDD
0.7 VDD
VDD
VDD
VDD
VDD
VDD
VDD
V
V
V
V
V
V
Conditions
VIL
MCLR and GP2 (Schmitt Trigger)
OSC1
OSC1
Input High Voltage
I/O ports
PIC12CE518/519 (Commercial)
PIC12CE518/519 (Industrial)
PIC12CE518/519 (Extended)
Pin at hi-impedance
4.5V < VDD ≤ 5.5V
Pin at hi-impedance
3.0V < VDD ≤ 4.5V
EXTRC option only(4)
XT and LP options
VIH
MCLR and GP2 (Schmitt Trigger)
OSC1 (Schmitt Trigger)
3.0V < VDD ≤ 4.5V
4.5V < VDD ≤ 5.5V(5)
Full VDD range(5)
EXTRC option only(4)
XT and LP options
IPUR
Input Leakage Current(2,3)
I/O ports
IIL
For VDD ≤ 5.5V
VSS ≤ VPIN ≤ VDD,
Pin at hi-impedance
VPIN = VSS + 0.25V(2)
VPIN = VDD
VSS ≤ VPIN ≤ VDD,
XT and LP options
–1
0.5
+1
µA
MCLR
20
OSC1
–3
130
0.5
0.5
250
+5
+3
µA
µA
µA
0.6
V
IOL = 8.7 mA, VDD = 4.5V
V
IOH = –5.4 mA, VDD = 4.5V
Output Low Voltage
I/O ports
Vol
Output High Voltage(3,4)
I/O ports
VoH
VDD –0.7
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is based on characterization results at 25°C. This data is for design guidance only and is not tested.
2: The leakage current on the MCLR/VPP 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
voltage.
3: Negative current is defined as coming out of the pin.
4: For PIC12CE5XX devices, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the
PIC12CE5XX be driven with external clock in RC mode.
5: The user may use the better of the two specifications.
DS40172A-page 60
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 61 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
11.3
Timing Parameter Symbology and Load Conditions
The timing parameter symbols have been created following one of the following formats:
1. TppS2ppS
2. TppS
T
F
Frequency
T
Time
Lowercase subscripts (pp) and their meanings:
pp
2
to
mc
MCLR
ck
CLKOUT
osc
oscillator
cy
cycle time
os
OSC1
drt
device reset timer
t0
T0CKI
io
I/O port
wdt
watchdog timer
Uppercase letters and their meanings:
S
F
Fall
P
Period
H
High
R
Rise
I
Invalid (Hi-impedance)
V
Valid
L
Low
Z
Hi-impedance
FIGURE 11-1: LOAD CONDITIONS - PIC12CE5XX
Pin
CL = 50 pF for all pins except OSC2
CL
VSS
 1997 Microchip Technology Inc.
15 pF for OSC2 in XT or LP modes
when external clock is used
to drive OSC1
Preliminary
DS40172A-page 61
12CF5XX_GEBook Page 62 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
11.4
Timing Diagrams and Specifications
FIGURE 11-2: EXTERNAL CLOCK TIMING - PIC12CE5XX
Q4
Q1
Q3
Q2
Q4
Q1
OSC1
1
3
3
4
4
2
TABLE 11-1:
EXTERNAL CLOCK TIMING REQUIREMENTS - PIC12CE5XX
AC Characteristics
Parameter
No.
Sym
FOSC
Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial),
–40°C ≤ TA ≤ +85°C (industrial),
–40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in Section 11.1
Characteristic
External CLKIN Frequency(2)
Oscillator Frequency
1
Tosc
External CLKIN Period
Oscillator Period
2
3
4
Tcy
(2)
(2)
(2)
Instruction Cycle Time
(3)
TosL, TosH Clock in (OSC1) Low or High Time
TosR, TosF Clock in (OSC1) Rise or Fall Time
Min
Typ(1)
DC
—
4
DC
—
200
DC
—
4
MHz EXTRC osc mode
MHz XT osc mode
Max
Units
Conditions
MHz XT osc mode
kHz
LP osc mode
0.1
—
4
DC
—
200
kHz
LP osc mode
250
—
—
ns
XT osc mode
5
—
—
ms
LP osc mode
250
—
—
ns
EXTRC osc mode
250
—
10,000
ns
XT osc mode
5
—
—
ms
LP osc mode
—
4/FOSC
—
—
50*
—
—
ns
XT oscillator
2*
—
—
ms
LP oscillator
—
—
25*
ns
XT oscillator
—
—
50*
ns
LP oscillator
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
2: 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.
When an external clock input is used, the “max” cycle time limit is “DC” (no clock) for all devices.
3: Instruction cycle period (TCY) equals four times the input oscillator time base period.
DS40172A-page 62
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 63 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 11-3:
I/O TIMING - PIC12CE5XX
Q1
Q4
Q2
Q3
OSC1
I/O Pin
(input)
17
I/O Pin
(output)
18
19
New Value
Old Value
20, 21
Note: All tests must be done with specified capacitive loads (see data sheet) 50 pF on I/O pins and CLKOUT.
TABLE 11-2:
TIMING REQUIREMENTS - PIC12CE5XX
AC Characteristics
Parameter
No.
Sym
Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial)
–40°C ≤ TA ≤ +85°C (industrial)
–40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in Section 11.1
Characteristic
Min
Typ(1)
Max
Units
—
—
100*
ns
17
TosH2ioV
OSC1↑ (Q1 cycle) to Port out valid
18
TosH2ioI
OSC1↑ (Q2 cycle) to Port input invalid
(I/O in hold time)
TBD
—
—
ns
19
TioV2osH
Port input valid to OSC1↑
(I/O in setup time)
TBD
—
—
ns
20
TioR
Port output rise time(3)
—
10
25**
ns
21
TioF
—
10
25**
ns
(3)
Port output fall
time(3)
* These parameters are characterized but not tested.
** These parameters are design targets and are not tested. No characterization data available at this time.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25˚C unless otherwise stated. These parameters are for design
guidance only and are not tested.
2: Measurements are taken in EXTRC mode.
3: See Figure 11-1 for loading conditions.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 63
12CF5XX_GEBook Page 64 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 11-4: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER TIMING - PIC12CE5XX
VDD
MCLR
30
Internal
POR
32
32
32
DRT
Timeout
(Note 2)
Internal
RESET
Watchdog
Timer
RESET
31
34
34
I/O pin
(Note 1)
Note 1: I/O pins must be taken out of hi-impedance mode by enabling the output drivers in software.
2: Runs in MCLR or WDT reset only in XT and LP modes.
TABLE 11-3:
RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER - PIC12CE5XX
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial)
–40°C ≤ TA ≤ +85°C (industrial)
–40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in Section 11.1
Parameter
No.
Sym
30
TmcL
MCLR Pulse Width (low)
2000*
—
—
ns
VDD = 5 V
31
Twdt
Watchdog Timer Time-out Period
(No Prescaler)
9*
18*
30*
ms
VDD = 5 V (Commercial)
32
TDRT
Device Reset Timer Period(2)
9*
18*
30*
ms
VDD = 5 V (Commercial)
34
TioZ
I/O Hi-impedance from MCLR Low
—
—
2000*
ns
Characteristic
Min
Typ(1)
Max
Units
Conditions
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
TABLE 11-4:
DRT (DEVICE RESET TIMER PERIOD) TIME OUT
Oscillator Configuration
POR Reset
Subsequent Resets
IntRC & ExtRC
18 ms (typical)
300 µs (typical)
XT & LP
18 ms (typical)
18 ms (typical)
DS40172A-page 64
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 65 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 11-5: TIMER0 CLOCK TIMINGS - PIC12CE5XX
T0CKI
40
41
42
TABLE 11-5:
TIMER0 CLOCK REQUIREMENTS - PIC12CE5XX
AC Characteristics
Standard Operating Conditions (unless otherwise specified)
Operating Temperature
0°C ≤ TA ≤ +70°C (commercial)
–40°C ≤ TA ≤ +85°C (industrial)
–40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in Section 11.1.
Parameter
Sym Characteristic
No.
40
Min
Tt0H T0CKI High Pulse Width - No Prescaler
0.5 TCY + 20*
—
—
ns
10*
—
—
ns
- With Prescaler
41
Tt0L
T0CKI Low Pulse Width - No Prescaler
0.5 TCY + 20*
—
—
ns
10*
—
—
ns
20 or TCY + 40*
N
—
—
ns
- With Prescaler
42
Tt0P T0CKI Period
Typ(1) Max Units Conditions
Whichever is greater.
N = Prescale Value
(1, 2, 4,..., 256)
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only
and are not tested.
FIGURE 11-6: EEPROM MEMORY BUS TIMING DATA
THIGH
TF
SCL
TSU:STA
TLOW
SDA
IN
TR
TSP
TSU:DAT
THD:DAT
TSU:STO
THD:STA
TBUF
TAA
SDA
OUT
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 65
12CF5XX_GEBook Page 66 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
TABLE 11-6:
EEPROM MEMORY BUS TIMING REQUIREMENTS
AC Characteristics
Parameter
Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C ≤ TA ≤ +70°C, Vcc = 3.0V to 5.5V (commercial)
–40°C ≤ TA ≤ +85°C, Vcc = 3.0V to 5.5V (industrial)
–40°C ≤ TA ≤ +125°C, Vcc = 4.5V to 5.5V (extended)
Operating Voltage VDD range is described in Section 11.1
Symbol
Min
Max
Units
Clock frequency
FCLK
—
—
—
100
100
400
kHz
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
Clock high time
THIGH
4000
4000
600
—
—
—
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
Clock low time
TLOW
4700
4700
1300
—
—
—
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
TR
—
—
—
1000
1000
300
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
SDA and SCL rise time
(Note 1)
SDA and SCL fall time
Conditions
TF
—
300
ns
(Note 1)
START condition hold time
THD:STA
4000
4000
600
—
—
—
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
START condition setup time
TSU:STA
4700
4700
600
—
—
—
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
Data input hold time
THD:DAT
0
—
ns
(Note 2)
Data input setup time
TSU:DAT
250
250
100
—
—
—
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
STOP condition setup time
TSU:STO
4000
4000
600
—
—
—
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
Output valid from clock
(Note 2)
TAA
—
—
—
3500
3500
900
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
Bus free time: Time the bus must
be free before a new transmission
can start
TBUF
4700
4700
1300
—
—
—
ns
4.5V ≤ Vcc ≤ 5.5V (E Temp range)
3.0V ≤ Vcc ≤ 4.5V
4.5V ≤ Vcc ≤ 5.5V
Output fall time from VIH
minimum to VIL maximum
TOF
20+0.1
CB
250
ns
(Note 1), CB ≤ 100 pF
Input filter spike suppression
(SDA and SCL pins)
TSP
—
50
ns
(Notes 1, 3)
Write cycle time
TWC
Endurance
—
4
ms
1M
—
cycles
25°C, VCC = 5.0V, Block Mode (Note 4)
Note 1: Not 100% tested. CB = total capacitance of one bus line in pF.
2: As a transmitter, the device must provide an internal minimum delay time to bridge the undefined region
(minimum 300 ns) of the falling edge of SCL to avoid unintended generation of START or STOP conditions.
3: The combined TSP and VHYS specifications are due to new Schmitt trigger inputs which provide improved
noise spike suppression. This eliminates the need for a TI specification for standard operation.
4: This parameter is not tested but guaranteed by characterization. For endurance estimates in a specific
application, please consult the Total Endurance Model which can be obtained on Microchip’s BBS or website.
DS40172A-page 66
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 67 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
TABLE 11-7:
VDD (Volts)
PULL-UP RESISTOR RANGES
Temperature (°C)
Min
Typ
Max
Units
32K
38K
39K
42K
17K
20K
22K
24K
35K
43K
43K
60K
20K
23K
25K
28K
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
326K
390K
427K
472K
292K
341K
371K
407K
395K
492K
500K
567K
360K
437K
448K
500K
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
GP0/GP1
3.0
5.5
-40
25
85
125
-40
25
85
125
27K
33K
33K
37K
15K
18K
19K
22K
-40
25
85
125
-40
25
85
125
271K
327K
348K
400K
247K
288K
306K
351K
GP3
3.0
5.5
*
These parameters are characterized but not tested.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 67
12CF5XX_GEBook Page 68 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
NOTES:
DS40172A-page 68
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 69 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
12.0
DC AND AC CHARACTERISTICS - PIC12CE5XX
The graphs and tables provided in this section are for design guidance and are not tested or guaranteed. In some
graphs or tables the data presented are outside specified operating range (e.g., outside specified VDD range). This is
for information only and devices will operate properly only within the specified range.
The data presented in this section is a statistical summary of data collected on units from different lots over a period of
time. “Typical” represents the mean of the distribution while “max” or “min” represents (mean + 3σ) and (mean – 3σ)
respectively, where σ is standard deviation.
FIGURE 12-1: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (VDD = 5.0V)
(INTERNAL RC IS CALIBRATED TO 25°C, 5.0V)
Not available at this time.
FIGURE 12-2: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (VDD = 3.0V)
(INTERNAL RC IS CALIBRATED TO 25°C, 5.0V)
Not available at this time.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 69
12CF5XX_GEBook Page 70 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 12-3: INTERNAL RC FREQUENCY VS. CALIBRATION VALUE (VDD = 5.5V)
Not available at this time.
FIGURE 12-4: INTERNAL RC FREQUENCY VS. CALIBRATION VALUE (VDD = 3.0V)
Not available at this time.
TABLE 12-1:
Oscillator
DYNAMIC IDD (TYPICAL) - WDT ENABLED, 25°C
Frequency
VDD =3.0V
External RC
4 MHz
300 µA*
Internal RC
4 MHz
520 µA
XT
4 MHz
300 µA
LP
32 KHz
10 µA
*Does not include current through external R&C.
DS40172A-page 70
VDD = 5.5V
620 µA*
1.1 mA
775 µA
37 µA
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 71 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 12-5: WDT TIMER TIME-OUT
PERIOD vs. VDD
FIGURE 12-6: SHORT DRT PERIOD VS. VDD
1000
50
900
45
800
40
700
WDT period (µs)
WDT period (µs)
35
30
25
Max +125°C
Max +125°C
Max +85°C
300
Typ +25°C
15
500
400
Max +85°C
20
600
Typ +25°C
200
MIn –40°C
10
MIn –40°C
100
2
5
2
3
4
5
VDD (Volts)
 1997 Microchip Technology Inc.
6
7
Preliminary
3
4
5
VDD (Volts)
6
7
DS40172A-page 71
12CF5XX_GEBook Page 72 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
FIGURE 12-7: IOH vs. VOH, VDD = 3.5 V
FIGURE 12-9: IOL vs. VOL, VDD = 3.5 V
0
35
-5
30
25
5
12
°C
0°
C
n+
5°C
-20
Typ
+2
20
C
M
5°
°C
85
n+
Mi
+2
-15
15
in
M
0°C
x
Ma
–4
ax
Ty
p
Mi
IOL (mA)
IOH (mA)
-10
–4
5°
C
+8
in
25
°C
+1
M
10
-25
5
-30
1.5
2.0
2.5
3.0
3.5
0
VOH (Volts)
0
500.0m
750.0m
1.0
VOL (Volts)
FIGURE 12-8: IOH vs. VOH, VDD = 5.5 V
FIGURE 12-10: IOL vs. VOL, VDD = 5.5 V
0
50
-5
Max –40°C
40
30
-15
25
Min +85°C
20
Min +125°C
0°
–4
-25
C
Ty
p
+2
5
M
°C
in
M
°C
+1
+8
5°
in
C
-20
Typ +25°C
IOL (mA)
IOH (mA)
-10
M
ax
10
-30
3.5
4.0
4.5
5.0
5.5
0
VOH (Volts)
250.0m
500.0m
750.0m
1.0
VOL (Volts)
DS40172A-page 72
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 73 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
13.0
PACKAGING INFORMATION
13.1
Package Marking Information
8-Lead PDIP (300 mil)
Example
MMMMMMMM
XXXXXCDE
AABB
12CE518
04I/PSAZ
9625
Example
8-Lead SOIC (208 mil)
MMMMMMM
XXXXXXX
AABBCDE
12CE518
04I/SM
9624SAZ
8-Lead Windowed Ceramic Side Brazed (300 mil)
Example
JW
MM
12CE518
MMMMMMM
Legend: MM...M
XX...X
AA
BB
C
Microchip part number information
Customer specific information*
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Facility code of the plant at which wafer is manufactured
C = Chandler, Arizona, U.S.A.,
S = Tempe, Arizona, U.S.A.
D
Mask revision number
E
Assembly code of the plant or country of origin in which
part was assembled
Note: 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.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 73
12CF5XX_GEBook Page 74 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
13.2
8-Lead Plastic Dual In-line (300 mil)
N
α
C
E1 E
eA
eB
Pin No. 1
Indicator
Area
D
S
S1
Base
Plane
Seating
Plane
L
B1
e1
B
A1 A2 A
D1
Package Group: Plastic Dual In-Line (PLA)
Millimeters
Inches
Symbol
Min
Max
Min
Max
α
0°
10°
0°
10°
A
A1
A2
B
B1
C
D
D1
E
E1
e1
eA
eB
L
N
S
S1
–
0.381
3.048
0.355
1.397
0.203
9.017
7.620
7.620
6.096
2.489
7.620
7.874
3.048
8
0.889
0.254
4.064
–
3.810
0.559
1.651
0.381
10.922
7.620
8.255
7.112
2.591
7.620
9.906
3.556
8
–
–
–
0.015
0.120
0.014
0.055
0.008
0.355
0.300
0.300
0.240
0.098
0.300
0.310
0.120
8
0.035
0.010
0.160
–
0.150
0.022
0.065
0.015
0.430
0.300
0.325
0.280
0.102
0.300
0.390
0.140
8
–
–
DS40172A-page 74
Notes
Typical
Reference
Typical
Reference
Preliminary
Notes
Typical
Reference
Typical
Reference
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 75 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
13.3
8-Lead Plastic Surface Mount (SOIC - Medium, 208 mil Body)
e
h x 45°
B
N
Index
Area
E
H
α
C
L
Chamfer
h x 45°
1
2
3
D
Seating
Plane
Base
Plane
CP
A1
A
Package Group: Plastic SOIC (SM)
Millimeters
Inches
Symbol
Min
Max
Min
Max
α
0°
8°
0°
8°
A
A1
B
C
D
E
e
H*
h
L
N
CP
1.778
0.101
0.355
0.190
5.080
5.156
1.270
7.670
0.381
0.508
14
–
2.00
0.249
0.483
0.249
5.334
5.411
1.270
8.103
0.762
1.016
14
0.102
0.070
0.004
0.014
0.007
0.200
0.203
0.050
0.302
0.015
0.020
14
–
0.079
0.010
0.019
0.010
0.210
0.213
0.050
0.319
0.030
0.040
14
0.004
 1997 Microchip Technology Inc.
Notes
Reference
Preliminary
Notes
Reference
DS40172A-page 75
12CF5XX_GEBook Page 76 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
13.4
8-Lead Ceramic Side Brazed Dual In-Line with Window (JW) (300 mil)
N
α
E1 E
C
eA
eB
Pin No. 1
Indicator
Area
D
S
S1
Base
Plane
Seating
Plane
L
B1
e1
B
A1 A3 A A2
D1
Package Group: Ceramic Side Brazed Dual In-Line (CER)
Millimeters
Inches
Symbol
α
A
A1
A2
A3
B
B1
C
D
D1
E
E1
e1
eA
eB
L
S
S1
DS40172A-page 76
Min
Max
0°
3.937
0.635
2.921
1.778
0.406
1.371
0.228
13.004
7.416
7.569
7.112
2.540
7.620
7.620
3.302
2.540
0.127
10°
5.030
1.143
3.429
2.413
0.508
1.371
0.305
13.412
7.824
8.230
7.620
2.540
7.620
9.652
4.064
3.048
—
Notes
Typical
Typical
BSC
Typical
BSC
Preliminary
Min
Max
0°
0.155
0.025
0.115
0.070
0.016
0.054
0.009
0.512
0.292
0.298
0.280
0.100
0.300
0.300
0.130
0.100
0.005
10°
0.198
0.045
0.135
0.095
0.020
0.054
0.012
0.528
0.308
0.324
0.300
0.100
0.300
0.380
0.160
0.120
—
Notes
Typical
Typical
BSC
Typical
BSC
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 77 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
14.0
APPENDIX A
The following example requires:
The following routines are written for 4 MHz clock operation, where the worst case timing occurs; the routines
can be used at lower frequencies without modification.
For those using clock speeds much less than 4MHz, it
may be possible to reduce code size by removing some
of the NOPs (see code listing).
14.1
SDA and SCL
The EEPROM interface is a 2-wire bus protocol consisting of data (SDA) and a clock (SCL). Although
these lines are mapped into the GPIO register, they are
not accessible as external pins; only to the internal
EEPROM peripheral. SDA and SCL operation is also
slightly different than GPO-GP5 as listed below.
Namely, to avoid code overhead in modifying the TRIS
register, both SDA and SCL are always outputs. To
read data from the EEPROM peripheral requires outputting a ‘1’ on SDA placing it in high-Z state, where
only the internal 100K pull-up is active on the SDA line.
SDA:
• Code Space: 77 words
• RAM Space: 5 bytes (4 are overlayable)
• Stack Levels:1 (The call to the function itself. The
functions do not call any lower level functions.)
• Timing:
- WRITE_BYTE takes 328 cycles
- READ_CURRENT takes 212 cycles
- READ_RANDOM takes 416 cycles.
• IO Pins: 0 (No external IO pins are used)
This code must reside in the lower half of a page. The
code achieves it’s small size without additional calls
through the use of a sequencing table. The table is a
list of procedures that must be called in order. The
table uses an ADDWF PCL,F instruction, effectively a
computed goto, to sequence to the next procedure.
However the ADDWF PCL,F instruction yields an 8 bit
address, forcing the code to reside in the first 256
addresses of a page.
Built-in 100K pull-up to VDD
Open-drain (pull-down only)
Always an output, regardless of TRIS<6>
Outputs a ‘1’ on reset
SCL:
Full CMOS output
Always an output regardless of TRIS<7>
Outputs a ‘1’ on reset
14.2
Example Code for Reading/Writing to EEPROM Data Memory
TITLE "PIC with EEPROM Data Memory Interface"
LIST P=12CE518
; Change to 12CE519 if using PIC12CE519
#include <p12CE518.inc>
;
;
Program:
EEPROM.ASM
;
Revision Date:
;
10-10-97
Adapted to 12CE51x parts
;
; PIC12CE51X EEPROM communication code. This code should be linked in
; with the application. These routines provide the following functionality:
; write byte random address
; read byte random address
; read byte next address
;
; read sequential is not supported.
;
; If the operation is successful, bit 7 of PC_OFFSET will be set, and
; the functions will return W=1. If the memory is busy with a write
; cycle, it will not ACK the command. The functions will return with
; bit 7 of PC_OFFSET cleared and and W will be set to 0.
;
; Based on Franco code.
;
; Must reside on the lower half of code page (address 0-FF).
;
; This provides users with highly compressed assembly code for
; communication between the EEPROM and the Microcontroller, which
; leaves a maximum amount of code space for the core application.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 77
12CF5XX_GEBook Page 78 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
;
; NOPs have been added to meet the timing specs for the memory at 4 MHz
; and low voltage. Applications running at slower clock rates and those
; operating within 4.5-5.5V may be able to remove some of the NOPs.
;
; This code is specifically written for the interface hardware of the
; 12CE51x parts. See AN571 for the unmodified routines.
;***************************************************************************
;*************************** EEPROM Subroutines **************************
;***************************************************************************
; Communication for EEPROM based on I2C protocol, with Acknowledge.
;
; Byte_Write: Byte write routine
;
Inputs:
EEPROM Address
EEADDR
;
EEPROM Data
EEDATA
;
Outputs:
Return 01 in W if OK, else return 00 in W
;
; Read_Current:
Read EEPROM at address currently held by EE device.
;
Inputs:
NONE
;
Outputs:
EEPROM Data
EEDATA
;
Return 01 in W if OK, else return 00 in W
;
; Read_Random:
Read EEPROM byte at supplied address
;
Inputs:
EEPROM Address
EEADDR
;
Outputs:
EEPROM Data
EEDATA
;
Return 01 in W if OK, else return 00 in W
;
; Note: EEPROM subroutines will set bit 7 in PC_OFFSET register if the
;
EEPROM acknowledged OK, else that bit will be cleared. This bit
;
can be checked instead of refering to the value returned in W
;***************************************************************************
;
; OPERATION:
;
Byte Write:
;
load EEADDR and EEDATA
;
then CALL BYTE_WRITE
;
;
Read Random:
;
Load EEADDR
;
then CALL READ_RANDOM
;
data read returned in EEDATA
;
;
Read Current
;
no setup necessary
;
CALL READ_CURRENT
;
data read returned in EEDATA
;
;***************************************************************************
;
; These functions consume:
; 77 words Programming Memory
; 5 file registers which are overlayable. That is, they can share with
; other functions as long as they are mutually exclusive in time. See
; udata_ovr in the linker manual.
; 1 stack level (the call to the function itself. These functions do not
; call any lower level functions).
;
;
DS40172A-page 78
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 79 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
;***************************************************************************
;*************************** Variable Listing ****************************
;***************************************************************************
OK
EQU
01H
NO
EQU
00H
I2C_PORT
SCL
SDA
EQU
EQU
EQU
GPIO
07H
06H
; Port B control register, used for I2C
; EEPROM Clock, SCL (I/O bit 7)
; EEPROM Data, SDA (I/O bit 6)
EE_OK
EQU
07H
; Bit 7 in PC_OFFSET used as OK flag for EE
udata_ovr
PC_OFFSET
RES
1
EEADDR
EEBYTE
res
res
1
1
COUNTER
res
1
;
;
;
;
;
;
;
res
1
; EEPROM Data
PC offset register (low order 4 bits),
value based on operating mode of EEPROM.
Also, bit 7 used for EE_OK flag
EEPROM Address
Byte sent to or received from
EEPROM (control, address, or data)
Bit counter for serial transfer
udata
EEDATA
global
global
global
global
global
global
READ_CURRENT
READ_RANDOM
WRITE_BYTE
EEADDR
EEDATA
PC_OFFSET
;********************** Set up EEPROM control bytes ************************
;***************************************************************************
code
READ_CURRENT
MOVLW
B'10000100'
; PC offset for read current addr. EE_OK bit7='1'
MOVWF
PC_OFFSET
; Load PC offset
GOTO
INIT_READ_CONTROL
WRITE_BYTE
MOVLW
GOTO
B'10000000'
; PC offset for write byte.
INIT_WRITE_CONTROL
READ_RANDOM
MOVLW
B'10000011'
; PC offset for read random.
EE_OK: bit7 = '1'
EE_OK: bit7 = '1'
INIT_WRITE_CONTROL
MOVWF
PC_OFFSET
MOVLW
B'10100000'
; Load PC offset register, value preset in W
; Control byte with write bit, bit 0 = '0'
START_BIT
BCF
; Start bit, SDA and SCL preset to '1'
I2C_PORT,SDA
;******* Set up output data (control, address, or data) and counter ********
;***************************************************************************
PREP_TRANSFER_BYTE
MOVWF
EEBYTE
; Byte to transfer to EEPROM already in W
MOVLW
.8
; Counter to transfer 8 bits
MOVWF
COUNTER
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 79
12CF5XX_GEBook Page 80 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
;************ Clock out data (control, address, or data) byte ************
;***************************************************************************
OUTPUT_BYTE
BCF
I2C_PORT,SCL
; Set clock low during data set-up
RLF
EEBYTE, F
; Rotate left, high order bit into carry bit
BCF
I2C_PORT,SDA
; Set data low, if rotated carry bit is
SKPNC
;
a '1', then:
BSF
I2C_PORT,SDA
; reset data pin to a one, otherwise leave low
NOP
BSF
I2C_PORT,SCL
; clock data into EEPROM
DECFSZ COUNTER, F
; Repeat until entire byte is sent
GOTO
OUTPUT_BYTE
NOP
; Needed to meet Timing (Thigh=4000nS)
;************************** Acknowkedge Check *****************************
;***************************************************************************
BCF
I2C_PORT,SCL
; Set SCL low, 0.5us < ack valid < 3us
NOP
; Needed to meet Timing (Tlow= 4700nS)
BSF
I2C_PORT,SDA
GOTO
$+1
;
;
NOP
; Necessary for SCL Tlow at low voltage,
;
NOP
; Tlow=4700nS
BSF
I2C_PORT,SCL
; Raise SCL, EEPROM acknowledge still valid
BTFSC I2C_PORT,SDA
; Check SDA for acknowledge (low)
BCF
PC_OFFSET,EE_OK
; If SDA not low (no ack), set error flag
BCF
I2C_PORT,SCL
; Lower SCL, EEPROM release bus
BTFSS PC_OFFSET,EE_OK
; If no error continue, else stop bit
GOTO
STOP_BIT
;***** Set up program counter offset, based on EEPROM operating mode *****
;***************************************************************************
MOVF
PC_OFFSET,W
ANDLW
B'00001111'
ADDWF
PCL, F
GOTO
INIT_ADDRESS
;PC offset=0, write control done, send address
GOTO
INIT_WRITE_DATA
;PC offset=1, write address done, send data
GOTO
STOP_BIT
;PC offset=2, write done, send stop bit
GOTO
INIT_ADDRESS
;PC offset=3, write control done, send address
GOTO
INIT_READ_CONTROL
;PC offset=4, send read control
GOTO
READ_BIT_COUNTER
;PC offset=5, set counter and read byte
GOTO
STOP_BIT
;PC offset=6, random read done, send stop
;********** Initalize EEPROM data (address, data, or control) bytes ******
;***************************************************************************
INIT_ADDRESS
INCF
PC_OFFSET, F
; Increment PC offset to 2 (write) or to 4 (read)
MOVF
EEADDR,W
; Put EEPROM address in W, ready to send to EEPROM
GOTO
PREP_TRANSFER_BYTE
INIT_WRITE_DATA
INCF
PC_OFFSET, F
MOVF
EEDATA,W
GOTO
PREP_TRANSFER_BYTE
INIT_READ_CONTROL
BSF
I2C_PORT,SCL
BSF
I2C_PORT,SDA
INCF
PC_OFFSET, F
MOVLW B'10100001'
GOTO
START_BIT
DS40172A-page 80
; Increment PC offset to go to STOP_BIT next
; Put EEPROM data in W, ready to send to EEPROM
;
;
;
;
;
Raise SCL
raise SDA
Increment PC offset to go to READ_BIT_COUNTER next
Set up read control byte, ready to send to EEPROM
bit 0 = '1' for read operation
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 81 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
;************************** Read EEPROM data *****************************
;***************************************************************************
READ_BIT_COUNTER
BSF
I2C_PORT,SDA
; set data bit to 1 so we're not pulling bus down.
NOP
BSF
I2C_PORT,SCL
MOVLW .8
; Set counter so 8 bits will be read into EEDATA
MOVWF COUNTER
READ_BYTE
BSF
SETC
BTFSS
CLRC
RLF
BCF
bsf
DECFSZ
GOTO
I2C_PORT,SCL
I2C_PORT,SDA
EEDATA, F
I2C_PORT,SCL
I2C_PORT,SDA
COUNTER, F
READ_BYTE
;
;
;
;
;
;
;
;
;
Raise SCL, SDA valid. SDA still input from ack
Assume bit to be read = 1
Check if SDA = 1
if SDA not = 1 then clear carry bit
rotate carry bit (=SDA) into EEDATA;
Lower SCL
reset SDA
Decrement counter
Read next bit if not finished reading byte
BSF
I2C_PORT,SCL
NOP
BCF
I2C_PORT,SCL
;****************** Generate a STOP bit and RETURN ***********************
;***************************************************************************
STOP_BIT
BCF
I2C_PORT,SDA
; SDA=0, on TRIS, to prepare for transition to '1'
BSF
I2C_PORT,SCL
; SCL = 1 to prepare for STOP bit
GOTO
$+1
; equivalent 4 NOPs neccessary for I2C spec Tsu:sto = 4.7us
GOTO
$+1
BSF
I2C_PORT,SDA
; Stop bit, SDA transition to '1' while SCL high
BTFSS
RETLW
RETLW
PC_OFFSET,EE_OK
NO
OK
; Check for error
; if error, send back NO
; if no error, send back OK
;****************************************************************************
;************************ End EEPROM Subroutines **************************
end
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 81
12CF5XX_GEBook Page 82 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
NOTES:
DS40172A-page 82
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 83 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
INDEX
A
O
ALU ....................................................................................... 7
Applications........................................................................... 3
Architectural Overview .......................................................... 7
Assembler
MPASM Assembler..................................................... 54
B
Block Diagram
On-Chip Reset Circuit ................................................. 35
Timer0......................................................................... 25
TMR0/WDT Prescaler................................................. 28
Watchdog Timer.......................................................... 37
Brown-Out Protection Circuit .............................................. 38
C
CAL0 bit .............................................................................. 16
CAL1 bit .............................................................................. 16
CAL2 bit .............................................................................. 16
CAL3 bit .............................................................................. 16
CALFST bit ......................................................................... 16
CALSLW bit ........................................................................ 16
Carry ..................................................................................... 7
Clocking Scheme ................................................................ 10
Code Protection ............................................................ 29, 39
Configuration Bits................................................................ 29
Configuration Word ............................................................. 29
D
DC and AC Characteristics ................................................. 69
Development Support ......................................................... 53
Development Tools ............................................................. 53
Device Varieties .................................................................... 5
Digit Carry ............................................................................. 7
E
EEPROM Peripheral Operation .......................................... 21
F
Family of Devices.................................................................. 4
Features................................................................................ 1
FSR..................................................................................... 18
Fuzzy Logic Dev. System (fuzzyTECH-MP) .................... 55
I
I/O Interfacing ..................................................................... 19
I/O Port................................................................................ 19
I/O Programming Considerations........................................ 20
ICEPIC Low-Cost PIC16CXXX In-Circuit Emulator ............ 53
ID Locations .................................................................. 29, 39
INDF.................................................................................... 18
Indirect Data Addressing..................................................... 18
Instruction Cycle ................................................................. 10
Instruction Flow/Pipelining .................................................. 10
Instruction Set Summary..................................................... 42
K
KeeLoq Evaluation and Programming Tools.................... 55
L
Loading of PC ..................................................................... 17
M
Memory Organization.......................................................... 11
Data Memory .............................................................. 12
Program Memory ........................................................ 11
MP-DriveWay™ - Application Code Generator................... 55
MPLAB C ............................................................................ 55
MPLAB Integrated Development Environment Software .... 54
 1997 Microchip Technology Inc.
OPTION Register ............................................................... 15
OSC selection..................................................................... 29
OSCCAL Register .............................................................. 16
Oscillator Configurations .................................................... 30
Oscillator Types
HS............................................................................... 30
LP ............................................................................... 30
RC .............................................................................. 30
XT ............................................................................... 30
P
Package Marking Information ............................................. 73
Packaging Information ........................................................ 73
PC....................................................................................... 17
PICDEM-1 Low-Cost PICmicro Demo Board ..................... 54
PICDEM-2 Low-Cost PIC16CXX Demo Board................... 54
PICDEM-3 Low-Cost PIC16CXXX Demo Board ................ 54
PICMASTER In-Circuit Emulator ..................................... 53
PICSTART Plus Entry Level Development System......... 53
POR
Device Reset Timer (DRT) ................................... 29, 36
PD............................................................................... 38
Power-On Reset (POR).............................................. 29
TO............................................................................... 38
PORTA ............................................................................... 19
Power-Down Mode ............................................................. 39
Prescaler ............................................................................ 28
PRO MATE II Universal Programmer .............................. 53
Program Counter ................................................................ 17
Q
Q cycles .............................................................................. 10
R
RC Oscillator ...................................................................... 31
Read Modify Write .............................................................. 20
Register File Map ............................................................... 12
Registers
Special Function ......................................................... 13
Reset .................................................................................. 29
Reset on Brown-Out ........................................................... 38
S
SEEVAL Evaluation and Programming System .............. 55
SLEEP .......................................................................... 29, 39
Software Simulator (MPLAB-SIM) ...................................... 55
Special Features of the CPU .............................................. 29
Special Function Registers ................................................. 13
Stack................................................................................... 17
STATUS ................................................................................7
STATUS Register ............................................................... 14
T
Timer0
Switching Prescaler Assignment ................................ 28
Timer0 ........................................................................ 25
Timer0 (TMR0) Module .............................................. 25
TMR0 with External Clock .......................................... 27
Timing Diagrams and Specifications .................................. 62
Timing Parameter Symbology and Load Conditions .......... 61
TRIS Registers ................................................................... 19
W
Wake-up from SLEEP ........................................................ 39
Watchdog Timer (WDT)................................................ 29, 36
Period ......................................................................... 37
Programming Considerations ..................................... 37
Preliminary
DS40172A-page 83
12CF5XX_GEBook Page 84 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
Z
Zero bit .................................................................................. 7
LIST OF FIGURES
Figure 3-1:
Figure 3-2:
Figure 4-1:
Figure 4-2:
Figure 4-3:
Figure 4-4:
Figure 4-5:
Figure 4-6:
Figure 4-7:
Figure 4-8:
Figure 5-1:
Figure 5-2:
Figure 6-1:
Figure 6-2:
Figure 6-3:
Figure 6-4:
Figure 6-5:
Figure 6-6:
Figure 6-7:
Figure 6-8:
Figure 7-1:
Figure 7-2:
Figure 7-3:
Figure 7-4:
Figure 7-5:
Figure 8-1:
Figure 8-2:
Figure 8-3:
Figure 8-4:
Figure 8-5:
Figure 8-6:
Figure 8-7:
Figure 8-8:
Figure 8-9:
Figure 8-10:
Figure 8-11:
Figure 8-12:
Figure 8-13:
Figure 8-14:
Figure 8-15:
Figure 9-1:
Figure 11-1:
Figure 11-2:
PIC12CE5XX Block Diagram........................ 8
Clock/Instruction Cycle ............................... 10
Program Memory Map and Stack for the
PIC12CE5XX .............................................. 11
PIC12CE518 Register File Map.................. 12
PIC12CE519 Register File Map.................. 12
STATUS Register (Address:03h)................ 14
OPTION Register........................................ 15
OSCCAL Register (Address 8Fh)............... 16
Loading of PC Branch Instructions PIC12CE518/CE519................................... 17
Direct/Indirect Addressing........................... 18
Equivalent Circuit
for a Single I/O Pin...................................... 19
Successive I/O Operation ........................... 20
Data Transfer Sequence On The
Serial Bus ................................................... 22
Acknowledge Timing................................... 22
Control Byte format..................................... 22
Acknowledge Polling Flow .......................... 23
Byte Write ................................................... 23
Current Address Read ................................ 24
Random Read............................................. 24
Sequential Read ......................................... 24
Timer0 Block Diagram ................................ 25
Timer0 Timing: Internal Clock/No
Prescale...................................................... 26
Timer0 Timing: Internal Clock/
Prescale 1:2................................................ 26
Timer0 Timing With External Clock ............ 27
Block Diagram of the Timer0/WDT
Prescaler..................................................... 28
Configuration Word for PIC12CE5XX......... 29
Crystal Operation (or Ceramic
Resonator) (XT or LP OSC
Configuration) ............................................. 30
External Clock Input Operation
(XT or LP OSC Configuration) .................... 30
External Parallel Resonant Crystal
Oscillator Circuit.......................................... 31
External Series Resonant Crystal
Oscillator Circuit.......................................... 31
External RC Oscillator Mode ...................... 31
MCLR SELECT........................................... 34
Simplified Block Diagram of OnChip Reset Circuit....................................... 35
Time-Out Sequence on Power-Up
(MCLR Pulled Low)..................................... 35
Time-Out Sequence on Power-Up
(MCLR Tied to VDD): Fast VDD
Rise Time.................................................... 35
Time-Out Sequence on Power-Up
(MCLR Tied to VDD): Slow VDD
Rise Time.................................................... 36
Watchdog Timer Block Diagram ................. 37
Brown-Out Protection Circuit 1 ................... 38
Brown-Out Protection Circuit 2 ................... 38
Typical In-Circuit Serial Programming
Connection.................................................. 40
General Format for Instructions .................. 41
Load Conditions - PIC12CE5XX................. 61
External Clock Timing - PIC12CE5XX........ 62
DS40172A-page 84
Figure 11-3:
Figure 11-4:
I/O Timing - PIC12CE5XX .......................... 63
Reset, Watchdog Timer, and Device
Reset Timer Timing - PIC12CE5XX ........... 64
Figure 11-5: Timer0 Clock Timings - PIC12CE5XX........ 65
Figure 11-6: EEPROM Memory Bus Timing
Data ............................................................ 65
Figure 12-1: Calibrated Internal RC Frequency
Range vs. Temperature (VDD = 5.0V)
(internal RC is calibrated to 25°C, 5.0V) .... 69
Figure 12-2: Calibrated Internal RC Frequency
Range vs. Temperature (VDD = 3.0V)
(internal RC is calibrated to 25°C, 5.0V) .... 69
Figure 12-3: Internal RC Frequency vs. calibration
value (VDD = 5.5V) ..................................... 70
Figure 12-4: Internal RC Frequency vs. calibration
value (VDD = 3.0V) ..................................... 70
Figure 12-5: WDT Timer Time-out Period vs. VDD ......... 71
Figure 12-6: Short DRT period vs. vDD ........................... 71
Figure 12-7: IOH vs. VOH, VDD = 3.5 V............................ 72
Figure 12-8: IOH vs. VOH, VDD = 5.5 V............................ 72
Figure 12-9: IOL vs. VOL, VDD = 3.5 V............................. 72
Figure 12-10: IOL vs. VOL, VDD = 5.5 V............................. 72
LIST OF TABLES
Table 1-1:
Table 3-1:
Table 4-1:
Table 5-1:
Table 7-1:
Table 8-1:
Table 8-2:
Table 8-3:
Table 8-4:
Table 8-5:
Table 8-6:
Table 8-7:
Table 8-8:
Table 9-1:
Table 9-2:
Table 10-1:
Table 11-1:
Table 11-2:
Table 11-3:
Table 11-4:
Table 11-5:
Table 11-6:
Table 11-7:
Table 12-1:
PIC12CXXX Family of Devices ...................... 4
PIC12CE5XX Pinout description.................... 9
Special Function Register (SFR)
Summary...................................................... 13
Summary of Port Registers .......................... 19
Registers Associated With Timer0 ............... 26
Capacitor Selection for Ceramic
Resonators - PIC12CE5XX.......................... 30
Capacitor Selection
for Crystal Oscillator - PIC12CE5XX............ 30
Reset Conditions for Registers .................... 33
Reset Condition for Special Registers ......... 33
DRT (Device Reset Timer Period) ............... 36
Summary of Registers Associated
with the Watchdog Timer ............................. 37
TO/PD/GPWUF Status After Reset.............. 38
Events Affecting TO/PD Status Bits ............. 38
OPCODE Field Descriptions ........................ 41
Instruction Set Summary.............................. 42
Development Tools From Microchip ............ 56
External Clock Timing Requirements PIC12CE5XX ............................................... 62
Timing Requirements - PIC12CE5XX .......... 63
Reset, Watchdog Timer, and Device
Reset Timer - PIC12CE5XX ........................ 64
DRT (Device Reset Timer Period)
Time Out ...................................................... 64
Timer0 Clock Requirements PIC12CE5XX ............................................... 65
EEPROM Memory Bus Timing
Requirements............................................... 66
Pull-up Resistor Ranges .............................. 67
Dynamic iDD (typical) - wdt enabled,
25°C ............................................................. 70
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 85 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
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Connecting to the Microchip BBS
Connect worldwide to the Microchip BBS using either
the Internet or the CompuServe communications network.
Internet:
You can telnet or ftp to the Microchip BBS at the
address:
mchipbbs.microchip.com
CompuServe Communications Network:
When using the BBS via the Compuserve Network,
in most cases, a local call is your only expense. The
Microchip BBS connection does not use CompuServe
membership services, therefore you do not need
CompuServe membership to join Microchip's BBS.
There is no charge for connecting to the Microchip BBS.
 1997 Microchip Technology Inc.
The procedure to connect will vary slightly from country
to country. Please check with your local CompuServe
agent for details if you have a problem. CompuServe
service allow multiple users various baud rates
depending on the local point of access.
The following connect procedure applies in most locations.
1. Set your modem to 8-bit, No parity, and One stop
(8N1). This is not the normal CompuServe setting
which is 7E1.
2. Dial your local CompuServe access number.
3. Depress the <Enter> key and a garbage string will
appear because CompuServe is expecting a 7E1
setting.
4. Type +, depress the <Enter> key and “Host Name:”
will appear.
5. Type MCHIPBBS, depress the <Enter> key and you
will be connected to the Microchip BBS.
In the United States, to find the CompuServe phone
number closest to you, set your modem to 7E1 and dial
(800) 848-4480 for 300-2400 baud or (800) 331-7166
for 9600-14400 baud connection. After the system
responds with “Host Name:”, type NETWORK, depress
the <Enter> key and follow CompuServe's directions.
For voice information (or calling from overseas), you
may call (614) 723-1550 for your local CompuServe
number.
Microchip regularly uses the Microchip BBS to distribute
technical information, application notes, source code,
errata sheets, bug reports, and interim patches for
Microchip systems software products. For each SIG, a
moderator monitors, scans, and approves or disapproves files submitted to the SIG. No executable files
are accepted from the user community in general to
limit the spread of computer viruses.
Systems Information and Upgrade Hot Line
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
1-602-786-7302 for the rest of the world.
Trademarks: The Microchip name, logo, PIC, PICSTART,
PICMASTER, PRO MATE and are registered trademarks
of Microchip Technology Incorporated in the U.S.A. and
other countries. PICmicro, FlexROM, MPLAB, and fuzzyLAB, are trademarks and SQTP is a service mark of
Microchip in the U.S.A.
fuzzyTECH is a registered trademark of Inform Software
Corporation. IBM, IBM PC-AT are registered trademarks of
International Business Machines Corp. Pentium is a trademark of Intel Corporation. Windows is a trademark and
MS-DOS, Microsoft Windows are registered trademarks
of Microsoft Corporation. CompuServe is a registered
trademark of CompuServe Incorporated.
All other trademarks mentioned herein are the property of
their respective companies.
Preliminary
DS40172A-page 85
12CF5XX_GEBook Page 86 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
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 (602) 786-7578.
Please list the following information, and use this outline to provide us with your comments about this Data Sheet.
To:
Technical Publications Manager
RE:
Reader Response
Total Pages Sent
From: Name
Company
Address
City / State / ZIP / Country
Telephone: (_______) _________ - _________
FAX: (______) _________ - _________
Application (optional):
Would you like a reply?
Device: PIC12CE5XX
Y
N
Literature Number: DS40172A
Questions:
1. What are the best features of this document?
2. How does this document meet your hardware and software development needs?
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?
6. Is there any incorrect or misleading information (what and where)?
7. How would you improve this document?
8. How would you improve our software, systems, and silicon products?
DS40172A-page 86
Preliminary
 1997 Microchip Technology Inc.
12CF5XX_GEBook Page 87 Tuesday, October 21, 1997 8:23 AM
PIC12CE5XX
PIC12CE5XX Product Identification System
Examples
PART NO. -XX X /XX XXX
Pattern:
Special Requirements
Package:
SM
P
JW
= 208 mil SOIC
= 300 mil PDIP
= 300 mil Windowed CERDIP
Temperature
Range:
I
E
04
=
=
=
=
Frequency
Range:
Device
0°C to +70°C
-40°C to +85°C
-40°C to +125°C
4 MHz
PIC12CE518
PIC12CE519
PIC12CE518T (Tape & reel for SOIC only)
PIC12CE519T (Tape & reel for SOIC only)
a)
PIC12CE518-04/P
Commercial Temp.,
PDIP Package, 4 MHz,
normal VDD limits
b)
PIC12CE518-04I/SM
Industrial Temp., SOIC
package, 4 MHz, normal
VDD limits
c)
PIC12CE519-04I/P
Industrial Temp.,
PDIP package, 4 MHz,
normal VDD limits
Please contact your local sales office for exact ordering procedures.
Sales and Support
Products supported by a preliminary Data Sheet may possibly 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. Your local Microchip sales office (see below)
2. The Microchip Corporate Literature Center U.S. FAX: (602) 786-7277
3. The Microchip’s Bulletin Board, via your local CompuServe number (CompuServe membership NOT required).
Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using.
For latest version information and upgrade kits for Microchip Development Tools, please call 1-800-755-2345 or 1-602-786-7302.
 1997 Microchip Technology Inc.
Preliminary
DS40172A-page 87
12CF5XX_GEBook Page 88 Tuesday, October 21, 1997 8:23 AM
M
WORLDWIDE SALES & SERVICE
AMERICAS
ASIA/PACIFIC
EUROPE
Corporate Office
Hong Kong
United Kingdom
Microchip Technology Inc.
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 602-786-7200 Fax: 602-786-7277
Technical Support: 602 786-7627
Web: http://www.microchip.com
Microchip Asia Pacific
RM 3801B, Tower Two
Metroplaza
223 Hing Fong Road
Kwai Fong, N.T., Hong Kong
Tel: 852-2-401-1200 Fax: 852-2-401-3431
Arizona Microchip Technology Ltd.
Unit 6, The Courtyard
Meadow Bank, Furlong Road
Bourne End, Buckinghamshire SL8 5AJ
Tel: 44-1628-851077 Fax: 44-1628-850259
Atlanta
India
Microchip Technology Inc.
500 Sugar Mill Road, Suite 200B
Atlanta, GA 30350
Tel: 770-640-0034 Fax: 770-640-0307
Microchip Technology Inc.
India Liaison Office
No. 6, Legacy, Convent Road
Bangalore 560 025, India
Tel: 91-80-229-0061 Fax: 91-80-559-9840
Arizona Microchip Technology SARL
Zone Industrielle de la Bonde
2 Rue du Buisson aux Fraises
91300 Massy, France
Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79
Boston
Microchip Technology Inc.
5 Mount Royal Avenue
Marlborough, MA 01752
Tel: 508-480-9990 Fax: 508-480-8575
Chicago
Microchip Technology Inc.
333 Pierce Road, Suite 180
Itasca, IL 60143
Tel: 630-285-0071 Fax: 630-285-0075
Dallas
Microchip Technology Inc.
14651 Dallas Parkway, Suite 816
Dallas, TX 75240-8809
Tel: 972-991-7177 Fax: 972-991-8588
Dayton
Microchip Technology Inc.
Two Prestige Place, Suite 150
Miamisburg, OH 45342
Tel: 937-291-1654 Fax: 937-291-9175
Los Angeles
Microchip Technology Inc.
18201 Von Karman, Suite 1090
Irvine, CA 92612
Tel: 714-263-1888 Fax: 714-263-1338
New York
Korea
Microchip Technology Korea
168-1, Youngbo Bldg. 3 Floor
Samsung-Dong, Kangnam-Ku
Seoul, Korea
Tel: 82-2-554-7200 Fax: 82-2-558-5934
Shanghai
Microchip Technology
RM 406 Shanghai Golden Bridge Bldg.
2077 Yan’an Road West, Hong Qiao District
Shanghai, PRC 200335
Tel: 86-21-6275-5700
Fax: 86 21-6275-5060
France
Germany
Arizona Microchip Technology GmbH
Gustav-Heinemann-Ring 125
D-81739 Müchen, Germany
Tel: 49-89-627-144 0 Fax: 49-89-627-144-44
Italy
Arizona Microchip Technology SRL
Centro Direzionale Colleoni
Palazzo Taurus 1 V. Le Colleoni 1
20041 Agrate Brianza
Milan, Italy
Tel: 39-39-6899939 Fax: 39-39-6899883
Singapore
JAPAN
Microchip Technology Taiwan
Singapore Branch
200 Middle Road
#07-02 Prime Centre
Singapore 188980
Tel: 65-334-8870 Fax: 65-334-8850
Microchip Technology Intl. Inc.
Benex S-1 6F
3-18-20, Shinyokohama
Kohoku-Ku, Yokohama-shi
Kanagawa 222 Japan
Tel: 81-45-471- 6166 Fax: 81-45-471-6122
Taiwan, R.O.C
8/29/97
Microchip Technology Taiwan
10F-1C 207
Tung Hua North Road
Taipei, Taiwan, ROC
Tel: 886 2-717-7175 Fax: 886-2-545-0139
Microchip Technology Inc.
150 Motor Parkway, Suite 416
Hauppauge, NY 11788
Tel: 516-273-5305 Fax: 516-273-5335
San Jose
Microchip Technology Inc.
2107 North First Street, Suite 590
San Jose, CA 95131
Tel: 408-436-7950 Fax: 408-436-7955
Toronto
Microchip Technology Inc.
5925 Airport Road, Suite 200
Mississauga, Ontario L4V 1W1, Canada
Tel: 905-405-6279 Fax: 905-405-6253
All rights reserved. © 1997, Microchip Technology Incorporated, USA. 10/97
Printed on recycled paper.
Information contained in this publication regarding device applications and the like is intended for suggestion only and may be superseded by updates. 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, 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.
DS40172A-page 88
 1997 Microchip Technology Inc.