Renesas M38857ME-XXXHP Single-chip 8-bit cmos microcomputer Datasheet

To all our customers
Regarding the change of names mentioned in the document, such as Mitsubishi
Electric and Mitsubishi XX, to Renesas Technology Corp.
The semiconductor operations of Hitachi and Mitsubishi Electric were transferred to Renesas
Technology Corporation on April 1st 2003. These operations include microcomputer, logic, analog
and discrete devices, and memory chips other than DRAMs (flash memory, SRAMs etc.)
Accordingly, although Mitsubishi Electric, Mitsubishi Electric Corporation, Mitsubishi
Semiconductors, and other Mitsubishi brand names are mentioned in the document, these names
have in fact all been changed to Renesas Technology Corp. Thank you for your understanding.
Except for our corporate trademark, logo and corporate statement, no changes whatsoever have been
made to the contents of the document, and these changes do not constitute any alteration to the
contents of the document itself.
Note : Mitsubishi Electric will continue the business operations of high frequency & optical devices
and power devices.
Renesas Technology Corp.
Customer Support Dept.
April 1, 2003
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
GENERAL DESCRIPTION
●Comparator circuit ...................................................... 8 channels
●Clock generating circuit ..................................... Built-in 2 circuits
(connect to external ceramic resonator or quartz-crystal oscillator)
●Power source voltage ................................................ 3.0 to 3.6 V
●Power dissipation
In high-speed mode .......................................................... 20 mW
(at 8 MHz oscillation frequency, at 3.3 V power source voltage)
In low-speed mode ......................................................... 330 mW
(at 32 kHz oscillation frequency, at 3.3 V power source voltage)
●Operating temperature range .................................... –20 to 85°C
The 3885 group is the 8-bit microcomputer based on the 740 family core technology.
The 3885 group is designed for Keyboard Controller for the note
book PC.
The multi-master I2C-bus interface can be added by option.
FEATURES
<Microcomputer mode>
●Basic machine-language instructions ...................................... 71
●Minimum instruction execution time .................................. 0.5 µs
(at 8 MHz oscillation frequency)
●Memory size
ROM ................................................................. 32K to 60K bytes
RAM ............................................................... 1024 to 2048 bytes
●Programmable input/output ports ............................................ 72
●Software pull-up transistors ....................................................... 8
●Interrupts ................................................. 22 sources, 16 vectors
●Timers ............................................................................. 8-bit ✕ 4
●Watchdog timer ............................................................ 16-bit ✕ 1
●PWM output .................................................................. 14-bit ✕ 2
●Serial I/O ....................... 8-bit ✕ 1(UART or Clock-synchronized)
●Multi-master I2C bus interface (option) ........................ 1 channel
●LPC interface .............................................................. 2 channels
●Serialized IRQ .................................................................. 3 factor
●A-D converter ............................................... 10-bit ✕ 8 channels
●D-A converter ................................................. 8-bit ✕ 2 channels
<Flash memory mode>
●Supply voltage ................................................. VCC = 3.3 ± 0.3V
●Program/Erase voltage ................................. VPP = 5.0 V ± 10 %
●Programming method ...................... Programming in unit of byte
●Erasing method
Parallel I/O mode
CPU reprogramming mode
●Program/Erase control by software command
●Number of times for programming/erasing ............................ 100
●Operating temperature range (at programming/erasing)
........................................................................ Room temperature
APPLICATION
Note book PC
42
41
44
43
48
47
46
45
51
50
49
61
40
62
63
64
65
66
67
68
69
70
71
72
73
74
75
39
38
37
36
35
34
33
M38857M8-XXXHP
M38858MC-XXXHP
M38859M8-XXXHP
M38859FFHP
32
31
30
29
28
P16
P17
P20/CMPREF
P21
P22
P23
P24(LED0)
P25(LED1)
P26(LED2)
P27(LED3)
VSS
XOUT
XIN
P40/XCOUT
P41/XCIN
RESET
CNVSS
VPP
P42/INT0
P43/INT1
P44/RXD
20
19
17
16
18
15
13
14
12
9
11
10
6
P60/AN0
P77/SCL
P76/SDA
P75/INT41
P74/INT31
P73/INT21
P72
P71
P70
P57/DA2/PWM11
P56/DA1/PWM01
P55/CNTR1
P54/CNTR0
P53/INT40
P52/INT30
P51/INT20
P50/INT5
P47/SRDY/CLKRUN
P46/SCLK
P45/TXD
7
8
22
21
3
4
5
79
80
2
76
77
78
27
26
25
24
23
1
P31/PWM10
P30/PWM00
P87/SERIRQ
P86/LCLK
P85/LRESET
P84/LFRAME
P83/LAD3
P82/LAD2
P81/LAD1
P80/LAD0
VCC
VREF
AVSS
P67/AN7
P66/AN6
P65/AN5
P64/AN4
P63/AN3
P62/AN2
P61/AN1
57
56
55
54
53
52
60
59
58
P32
P33
P34
P35
P36
P37
P00
P01
P02
P03
P04
P05
P06
P07
P10
P11
P12
P13
P14
P15
PIN CONFIGURATION (TOP VIEW)
: Flash memory version
Package type : 80P6Q-A
Fig. 1 Pin configuration
1
2
Fig. 2 Functional block diagram
29
XCIN
XCOUT
Sub-clock Sub-clock
input
output
Main-clock
output
XOUT
P7(8)
2 3 4 5 6 7 8 9
I/O port P7
63 64 65 66 67 68 69 70
I/O port P8
CLKRUN
Reset
P8(8)
LPC interface
S CL S DA
I C
2
Watchdog
timer
Clock generating circuit
28
Main-clock
input
XIN
72 73
AVSS
VREF
INT21,
INT31,
INT41
I/O port P5
I/O port P6
P5(8)
D-A
converter1
(8)
PC H
10 11 12 13 14 15 16 17
P6(8)
D-A
converter 2
(8)
ROM
74 75 76 77 78 79 80 1
A-D
converter
(10)
RAM
30
VSS
INT20,
INT30,
INT40,
INT5
PS
INT0,
INT1
I/O port P4
18 19 20 21 22 23 26 27
P4(8)
PC L
S
Y
X
A
SI/O(8)
C P U
71
VCC
FUNCTIONAL BLOCK DIAGRAM (Package : 80P6Q-A)
XCIN
XCOUT
P3(8)
CNTR0
I/O port P3
P2(8)
I/O port P2
P1(8)
I/O port P1
39 40 41 42 43 44 45 46
CMPREF
P0(8)
I/O port P0
47 48 49 50 51 52 53 54
PWM10,
PWM11
PWM00,
PWM01
31 32 33 34 35 36 37 38
Key-on
wake-up
PWM1(14)
Timer Y (8)
Timer X (8)
Timer 2 (8)
Timer 1 (8)
PWM0(14)
Prescaler Y (8)
Prescaler X (8)
Prescaler 12 (8)
CNTR1
24
CNVSS
55 56 57 58 59 60 61 62
Comparator
25
RESET
Reset input
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
PIN DESCRIPTION
Table 1 Pin description (1)
Pin
Functions
Name
Function except a port function
•Apply voltage of 3.0 V ±10 % to Vcc, and 0 V to Vss.
VCC, VSS
Power source
CNVSS
CNVSS input
VREF
Reference voltage
•Reference voltage input pin for A-D and D-A converters.
AVSS
Analog power source
•Analog power source input pin for A-D and D-A converters.
•Connect to VSS.
RESET
Reset input
•Reset input pin for active “L”.
XIN
Clock input
XOUT
Clock output
•Connected to VSS.
•In the flash memory version, this pin functions as the VPP power source input pin.
•Input and output pins for the clock generating circuit.
•Connect a ceramic resonator or quartz-crystal oscillator between the XIN and XOUT pins to set
the oscillation frequency.
•When an external clock is used, connect the clock source to the XIN pin and leave the XOUT
pin open.
•8-bit I/O port.
•I/O direction register allows each pin to be individually programmed as either input or output.
P00–P07
I/O port P0
•CMOS compatible input level.
•CMOS 3-state output structure or N-channel open-drain output structure.
•8-bit I/O port.
P10–P17
I/O port P1
•I/O direction register allows each pin to be individually programmed as either input or output.
•CMOS compatible input level.
•CMOS 3-state output structure or N-channel open-drain output structure.
•8-bit I/O port.
P20/CMPREF
I/O port P2
P21–P27
•I/O direction register allows each pin to be individually
programmed as either input or output.
•CMOS compatible input level.
•CMOS 3-state output structure.
•P24 to P27 (4 bits) are enabled to output large current for LED drive.
•8-bit I/O port.
P30/PWM00
P31/PWM10
•I/O direction register allows each pin to be individually
programmed as either input or output.
I/O port P3
P32–P37
•Comparator reference power source
input pin
•CMOS compatible input level.
•CMOS 3-state output structure.
•These pins function as key-on wake-up and comparator input.
•These pins are enabled to control pull-up.
•Key-on wake-up input pins
•Comparator input pins
•PWM output pins
•Key-on wake-up input pins
•Comparator input pins
3
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 2 Pin description (2)
Pin
Functions
Name
P40/XCOUT
P41/XCIN
•8-bit I/O port with the same function as port P0
P42/INT0
P43/INT1
CMOS compatible input level
P44/RxD
P45/TxD
P46/SCLK
<Input level>
I/O port P4
P47/SRDY
/CLKRUN
P50/INT5
P51/INT20
P52/INT30
P53/INT40
<Output level>
P40, P41 : CMOS 3-state output structure
Function except a port function
•Sub-clock generating circuit I/O
pins (Connect a resonator.)
•Interrupt input pins
P42-P47 : CMOS 3-state output structure or Nchannel open-drain output structure
•Serial I/O function pins
•Each pin level of P42 to P4 6 can be read even in
output port mode.
•Serial I/O function pins
•Serialized IRQ function pin
•8-bit I/O port with the same function as port P0
•CMOS compatible input level
•CMOS 3-state output structure
•Interrupt input pins
I/O port P5
P54/CNTR0
P55/CNTR1
•Timer X, timer Y function pins
•D-A converter output pins
P56/DA1/PWM01
P57/DA2/PWM11
•PWM output pins
•8-bit I/O port with the same function as port P0
P60/AN0–P67/AN7 I/O port P6
•CMOS compatible input level.
•A-D converter output pins
•CMOS 3-state output structure.
•8-bit CMOS I/O port with the same function as port P0
P70
P71
P72
P73/INT21
P74/INT31
P75/INT41
<Input level>
P70–P75 : CMOS compatible input level or
TTL compatible input level
I/O port P7
P76/SDA
P77/SCL
P80/LAD0
P81/LAD1
P82/LAD2
P83/LAD3
P84/LFRAME
P85/LRESET
P86/LCLK
P87/SERIRQ
4
P76, P77 : CMOS compatible input level or
SMBUS input level in the I2C-BUS
interface function,
<Output structure>
N-channel open-drain output structure
•Interrupt input pins
•I2C-BUS interface function pins
•Each pin level of P70 to P75 can be read evev in
output port mode.
•8-bit CMOS I/O port with the same function as port
P0
•CMOS compatible input level.
•CMOS 3-state output structure.
•LPC interface function pins
I/O port P8
•Serialized IRQ function pin
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
PART NUMBERING
Product name
M3885
8
M
C
-XXX
HP
Package type
HP : 80P6Q-A
ROM number
Omitted in the flash memory version.
ROM/Flash memory size
1 : 4096 bytes
2 : 8192 bytes
9: 36864 bytes
A: 40960 bytes
3 : 12288 bytes
B: 45056 bytes
C: 49152 bytes
D: 53248 bytes
4 : 16384 bytes
5 : 20480 bytes
6 : 24576 bytes
E: 57344 bytes
7 : 28672 bytes
F: 61440 bytes
8 : 32768 bytes
The first 128 bytes and the last 2 bytes of ROM are reserved
areas ; user cannot use those bytes.
However, they can be programmed or erased in the flash
memory version, so that the users can use them.
Memory type
M : Mask ROM version
F : Flash memory version
RAM size
0 : 192 bytes
1 : 256 bytes
2 : 384 bytes
3 : 512 bytes
4 : 640 bytes
5 : 768 bytes
6 : 896 bytes
7 : 1024 bytes
8 : 1536 bytes
9 : 2048 bytes
Fig. 3 Part numbering
5
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
GROUP EXPANSION
Packages
Mitsubishi plans to expand the 3885 group as follows.
80P6Q-A .................................. 0.5 mm-pitch plastic molded LQFP
Memory Type
Support for mask ROM, flash memory version.
Memory Size
ROM size ........................................................... 32 K to 60 K bytes
RAM size .......................................................... 1024 to 2048 bytes
Memory Expansion
ROM size (bytes)
ROM
external
M38859FF
60K
56K
48K
M38858MC
40K
32K
M38857M8
M38859M8
24K
16K
8K
256
512
768
1024
1280
RAM size (bytes)
1536
1792
2048
Fig. 4 Memory expansion plan
Table 3 Products plan list
6
As of May 2002
Product name
(P) ROM size (bytes)
ROM size for User in ( )
RAM size (bytes)
Package
M38857M8-XXXHP
M38858MC-XXXHP
M38859M8-XXXHP
M38859FFHP
32768 (32638)
49152 (19022)
32768 (32638)
61440
1024
1536
2048
2048
80P6Q-A
Remarks
Mask ROM version
Flash memory version
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
FUNCTIONAL DESCRIPTION
CENTRAL PROCESSING UNIT (CPU)
[Stack Pointer (S)]
The 3885 group uses the standard 740 Family instruction set. Refer to the table of 740 Family addressing modes and machine
instructions or the 740 Family Software Manual for details on the
instruction set.
Machine-resident 740 Family instructions are as follows:
The FST and SLW instructions cannot be used.
The STP, WIT, MUL, and DIV instructions can be used.
[Accumulator (A)]
The accumulator is an 8-bit register. Data operations such as data
transfer, etc., are executed mainly through the accumulator.
[Index Register X (X)]
The index register X is an 8-bit register. In the index addressing
modes, the value of the OPERAND is added to the contents of
register X and specifies the real address.
[Index Register Y (Y)]
The stack pointer is an 8-bit register used during subroutine calls
and interrupts. This register indicates start address of stored area
(stack) for storing registers during subroutine calls and interrupts.
The low-order 8 bits of the stack address are determined by the
contents of the stack pointer. The high-order 8 bits of the stack address are determined by the stack page selection bit. If the stack
page selection bit is “0” , the high-order 8 bits becomes “0016”. If
the stack page selection bit is “1”, the high-order 8 bits becomes
“0116”.
The operations of pushing register contents onto the stack and
popping them from the stack are shown in Figure 7.
Store registers other than those described in Figure 7 with program when the user needs them during interrupts or subroutine
calls.
[Program Counter (PC)]
The program counter is a 16-bit counter consisting of two 8-bit
registers PC H and PCL. It is used to indicate the address of the
next instruction to be executed.
The index register Y is an 8-bit register. In partial instruction, the
value of the OPERAND is added to the contents of register Y and
specifies the real address.
b0
b7
A
Accumulator
b0
b7
X
Index register X
b0
b7
Y
b7
Index register Y
b0
S
b15
b7
PCH
Stack pointer
b0
Program counter
PCL
b7
b0
N V T B D I Z C
Processor status register (PS)
Carry flag
Zero flag
Interrupt disable flag
Decimal mode flag
Break flag
Index X mode flag
Overflow flag
Negative flag
Fig. 5 740 Family CPU register structure
7
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
On-going Routine
Interrupt request
(Note)
M (S)
Execute JSR
Push return address
on stack
M (S)
(PCH)
(S)
(S) – 1
M (S)
(PCL)
(S)
(S)– 1
(S)
M (S)
(S)
M (S)
(S)
Subroutine
(S)
(S) + 1
(PCL)
M (S)
(S)
(S) + 1
(PCH)
M (S)
(S) – 1
(PCL)
Push return address
on stack
(S) – 1
(PS)
Push contents of processor
status register on stack
(S) – 1
Interrupt
Service Routine
Execute RTS
POP return
address from stack
(PCH)
I Flag is set from “0” to “1”
Fetch the jump vector
Execute RTI
Note: Condition for acceptance of an interrupt
(S)
(S) + 1
(PS)
M (S)
(S)
(S) + 1
(PCL)
M (S)
(S)
(S) + 1
(PCH)
M (S)
POP contents of
processor status
register from stack
POP return
address
from stack
Interrupt enable flag is “1”
Interrupt disable flag is “0”
Fig. 6 Register push and pop at interrupt generation and subroutine call
Table 4 Push and pop instructions of accumulator or processor status register
8
Push instruction to stack
Pop instruction from stack
Accumulator
PHA
PLA
Processor status register
PHP
PLP
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[Processor status register (PS)]
The processor status register is an 8-bit register consisting of 5
flags which indicate the status of the processor after an arithmetic
operation and 3 flags which decide MCU operation. Branch operations can be performed by testing the Carry (C) flag , Zero (Z) flag,
Overflow (V) flag, or the Negative (N) flag. In decimal mode, the Z,
V, N flags are not valid.
•Bit 0: Carry flag (C)
The C flag contains a carry or borrow generated by the arithmetic
logic unit (ALU) immediately after an arithmetic operation. It can
also be changed by a shift or rotate instruction.
•Bit 1: Zero flag (Z)
The Z flag is set if the result of an immediate arithmetic operation
or a data transfer is “0”, and cleared if the result is anything other
than “0”.
•Bit 2: Interrupt disable flag (I)
The I flag disables all interrupts except for the interrupt
generated by the BRK instruction.
Interrupts are disabled when the I flag is “1”.
•Bit 3: Decimal mode flag (D)
The D flag determines whether additions and subtractions are
executed in binary or decimal. Binary arithmetic is executed when
this flag is “0”; decimal arithmetic is executed when it is “1”.
Decimal correction is automatic in decimal mode. Only the ADC
•Bit 4: Break flag (B)
The B flag is used to indicate that the current interrupt was
generated by the BRK instruction. The BRK flag in the processor
status register is always “0”. When the BRK instruction is used to
generate an interrupt, the processor status register is pushed
onto the stack with the break flag set to “1”.
•Bit 5: Index X mode flag (T)
When the T flag is “0”, arithmetic operations are performed
between accumulator and memory. When the T flag is “1”, direct
arithmetic operations and direct data transfers are enabled
between memory locations.
•Bit 6: Overflow flag (V)
The V flag is used during the addition or subtraction of one byte
of signed data. It is set if the result exceeds +127 to -128. When
the BIT instruction is executed, bit 6 of the memory location
operated on by the BIT instruction is stored in the overflow flag.
•Bit 7: Negative flag (N)
The N flag is set if the result of an arithmetic operation or data
transfer is negative. When the BIT instruction is executed, bit 7 of
the memory location operated on by the BIT instruction is stored
in the negative flag.
Table 5 Set and clear instructions of each bit of processor status register
C flag
Z flag
I flag
D flag
B flag
T flag
V flag
N flag
Set instruction
SEC
–
SEI
SED
–
SET
–
–
Clear instruction
CLC
–
CLI
CLD
–
CLT
CLV
–
9
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[CPU Mode Register (CPUM)] 003B16
The CPU mode register contains the stack page selection bit, etc.
The CPU mode register is allocated at address 003B16.
b7
b0
1
CPU mode register
(CPUM : address 003B16)
Processor mode bits
b1 b0
0 0 : Single-chip mode
0 1 : Not available
1 0 : Not available
1 1 : Not available
Stack page selection bit
0 : 0 page
1 : 1 page
Fix this bit to “1”.
Port P40/P41 switch bit
0 : I/O port function (stop oscillating)
1 : XCIN–XCOUT oscillating function
Main clock (XIN–XOUT) stop bit
0 : Oscillating
1 : Stopped
Main clock division ratio selection bits
b7 b6
0 0 : φ = f(XIN)/2 (high-speed mode)
0 1 : φ = f(XIN)/8 (middle-speed mode)
1 0 : φ = f(XCIN)/2 (low-speed mode)
1 1 : Not available
Fig. 7 Structure of CPU mode register
10
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MEMORY
Zero Page
RAM
Access to this area with only 2 bytes is possible in the zero page
addressing mode.
RAM is used for data storage and for stack area of subroutine
calls and interrupts.
Special Page
ROM
Access to this area with only 2 bytes is possible in the special
page addressing mode.
ROM is used for program code and data table storage.
The first 128 bytes and the last 2 bytes of ROM are reserved for
device testing code and the rest is user area. Programming/Erasing of the reserved ROM area is possible in the flash memory
version.
Interrupt Vector Area
The interrupt vector area contains reset and interrupt vectors.
Special Function Register (SFR) Area
The special function register area contains the control registers
such as I/O ports, timers, serial I/O, etc.
000016
SFR area
RAM area
RAM size
(bytes)
1024
1536
2048
Zero page
004016
Address
XXXX16
RAM
043F16
063F16
083F16
010016
XXXX16
Not used
0FF016
0FFF16
SFR area
YYYY16
Reserved ROM area
(Note) (128 bytes)
ZZZZ16
ROM area
ROM size
(bytes)
Address
YYYY16
Address
ZZZZ16
32768
49152
61440
800016
400016
100016
808016
408016
108016
ROM
FF0016
FFDC16
Interrupt vector area
FFFE16
FFFF16
Special page
Reserved ROM area
(Note)
Notes: This area is reserved in the mask ROM version.
This area is usable in flash memory version.
Fig. 8 Memory map diagram
11
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
000016
Port P0 (P0)
002016
Prescaler 12 (PRE12)
000116
Port P0 direction register (P0D)
002116
Timer 1 (T1)
000216
Port P1 (P1)
002216
Timer 2 (T2)
000316
Port P1 direction register (P1D)
002316
Timer XY mode register (TM)
000416
Port P2 (P2)
002416
Prescaler X (PREX)
000516
Port P2 direction register (P2D)
002516
Timer X (TX)
000616
Port P3 (P3)
002616
Prescaler Y (PREY)
000716
Port P3 direction register (P3D)
002716
Timer Y (TY)
000816
Port P4 (P4)
002816
Data bas buffer register 0 (DBB0)
000916
Port P4 direction register (P4D)
002916
Data bas buffer status register 0 (DBBSTS0)
000A16
Port P5 (P5)
002A16 LPC control register (LPCCON)
000B16
Port P5 direction register (P5D)
002B16 Data bas buffer register 1 (DBB1)
000C16
Port P6 (P6)
002C16
Data bas buffer status register 1 (DBBSTS1)
000D16
Port P6 direction register (P6D)
002D16
Comparator data register (CMPD)
000E16
Port P7 (P7)
002E16 Port control register 1 (PCTL1)
000F16
Port P7 direction register (P7D)
002F16 Port control register 2 (PCTL2)
001016
Port P8 (P8)/Port P4 input register (P4I)
003016
PWM0H register (PWM0H)
001116
Port P8 direction register (P8D)/Port P7 input register (P7I)
003116
PWM0L register (PWM0L)
001216
I2C data shift register (S0)
003216
PWM1H register (PWM1H)
001316
I2C address register (S0D)
003316
PWM1L register (PWM1L)
001416
I2C status register (S1)
003416
AD/DA control register (ADCON)
001516
I2 C
control register (S1D)
003516
A-D conversion register 1 (AD1)
001616
I2 C
clock control register (S2)
003616
D-A1 conversion register (DA1)
001716
I2 C
start/stop condition control register (S2D)
003716
D-A2 conversion register (DA2)
001816
Transmit/Receive buffer register (TB/RB)
003816
A-D conversion register 2 (AD2)
001916
Serial I/O status register (SIOSTS)
003916
Interrupt source selection register (INTSEL)
001A16
Serial I/O control register (SIOCON)
003A16 Interrupt edge selection register (INTEDGE)
001B16
UART control register (UARTCON)
003B16 CPU mode register (CPUM)
001C16
Baud rate generator (BRG)
003C16
Interrupt request register 1 (IREQ1)
001D16
Serialized IRQ control register (SERCON)
003D16
Interrupt request register 2 (IREQ2)
001E16
Watchdog timer control register (WDTCON)
003E16 Interrupt control register 1 (ICON1)
001F16
Serialized IRQ request register (SERIRQ)
003F16 Interrupt control register 2 (ICON2)
0FF016 LPC0 address register L (LPC0ADL)
0FF116
LPC0 address register H (LPC0ADH)
0FF216
LPC1 address register L (LPC1ADL)
0FF316 LPC1 address register H (LPC1ADH)
0FF816
Port P5 input register (P5I)
0FF916 Port control register 3 (PCTL3)
0FFE16
Flash memory control register (FMCR)
(Note)
0FFF16
Reserved
(Note)
Note: This applies to only flash memory version.
Fig. 9 Memory map of special function register (SFR)
12
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
I/O PORTS
All I/O pins are programmable as input or output. All I/O ports
have direction registers which specify the data direction of each
pin like input/output. One bit in a direction register corresponds to
one pin. Each pin can be set to be input or output port.
Writing “0” to the bit corresponding to the pin, that pin becomes an
input mode. Writing “1” to the bit, that pin becomes an output
mode.
When the data is read from the bit of the port register corresponding to the pin which is set to output, the value shows the port latch
data, not the input level of the pin. When a pin set to input, the pin
comes floating. In input port mode, writing the port register
changes only the data of the port latch and the pin remains high
impedance state.
When the P8 function selection bit of the port control register 2 is
set to “1”, reading from address 001016 reads the port P4 register,
and reading from address 001116 reads the port P7 register.
Especially, the input level of P42 to P46 pins and P70 to P75 pins
can be read regardless of the data of the direction registers in this
case.
Table 6 I/O port function (1)
Pin
Name
P00-P07
Port P0
P10–P17
Port P1
Input/Output
I/O Structure
Non-Port Function
CMOS compatible
input level
CMOS 3-state output
or N-channel opendrain output
Analog comparator
power source input pin
P20/CMPREF
Related SFRs
Ref.No.
Port control register 1
(1)
Port control register 1
Port control register 2
(2)
Port P2
P21–P27
(3)
CMOS compatible
input level
CMOS 3-state output
PWM output
Key-on wake up input
Comparator input
Port control register 1
AD/DA control register
(4)
(5)
P32–P37
Key-on wake up input
Comparator input
Port control register 1
(6)
P40/XCOUT
P41/XCIN
Sub-clock generating
circuit
CPU mode register
(7)
(8)
External interrupt input
Interrupt edge selection
register
Port control register 2
(9)
(10)
Serial I/O function input
Serial I/O control register
Port control register 2
(11)
Serial I/O function output
Serial I/O control register
UART control register
Port control register 2
(12)
Serial I/O function I/O
Serial I/O control register
Port control register 2
(13)
Serial I/O control register
Serialized IRQ control
register
(14)
P30/PWM00
P31/PWM10
Port P3
Input/output,
individual bits
P42/INT0
P43/INT1
P44/RXD
Port P4
P45/TXD
P46/SCLK
P47/SRDY
/CLKRUN
CMOS compatible
input level
CMOS 3-state output
or N-channel opendrain output
Serial I/O function output
Serialized IRQ function
output
13
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 7 I/O port function (2)
Pin
Name
Input/Output
P50/INT5
P51/INT20
P52/INT30
P53/INT40
P54/CNTR0
P55/CNTR1
Related SFRs
Ref.No.
CMOS compatible
input level
CMOS 3-state output
or N-channel
opendrain output
External interrupt input
Interrupt edge selection
register
(15)
(16)
Timer X, timer Y function I/O
Timer XY mode register
(17)
D-A converter output
PWM output
AD/DA control register
UART control register
(18)
(19)
A-D converter input
AD/DA control register
(20)
Port control register 2
(21)
(22)
(23)
(24)
External interrupt input
Interrupt edge selection
register
Port control register 2
(25)
I2C-BUS interface function I/O
I2C control register
(26)
Data bus buffer control
register
(27)
(28)
CMOS compatible
input level
CMOS 3-state output
Port P6
P70
P71
P72
P73/INT21
P74/INT31
P75/INT41
Non-Port Function
Port P5
P56/DA1/
PWM01
P57/DA2/
PWM11
P60/AN0–
P67/AN7
I/O Format
Input/output,
individual bits
Port P7
CMOS compatible
input level or
TTL input level
Pure N-channel
open-drain output
CMOS compatible
input level or SMBUS
input level
Pure N-channel
open-drain output
P76/SDA
P77/SCL
P80/LAD0
P81/LAD1
P82/LAD2
P83/LAD3
P84/
LFRAME
P85/
LRESET
P86/LCLK
P87/
SERIRQ
Port P8
CMOS compatible
input level
CMOS 3-state output
LPC interface function
I/O
Serialized IRQ function
I/O
Notes1: For details usage of double-function ports as function I/O ports, refer to the applicable sections.
2: Make sure that the input level of each pin should be either 0 V or VCC in STP mode.
When an input level is at an intermediate voltage level, the ICC current will become large because of the input buffer gate.
14
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
(1) Ports P0, P1
(2) Port P20
P00–P03,
P04–P07,
P10–P13,
P14–P17 output structure
selection bits
Direction
register
Data bus
Direction
register
Port latch
Data bus
Port latch
Comparator reference power source input
Comparator reference input
pin select bit
(4) Ports P30, P31
(3) Port P21–P27
P30–P33 pull-up control bit
PWM0 (PWM1) output pin selection bit
PWM0(PWM1) enable bit
Direction
register
Data bus
Direction
register
Port latch
Data bus
Port latch
PWM00 (PWM10) output
(5) Ports P32–P37
(6) Port P40
P30–P33,
P34–P37 pull-up control bit
Port XC switch bit
Direction
register
Data bus
Direction
register
Data bus
Comparator input
Key-on wake-up input
Port latch
Port latch
Sub-clock oscillation circuit
Port P41
Port XC switch bit
Comparator input
Key-on wake-up input
(7) Port P41
(8) Ports P42 , P43
Port XC switch bit
P4 output structure selection bit
Direction
register
Data bus
Direction
register
Port latch
Data bus
Sub-clock oscillation circuit
Port latch
✻1
Interrupt input
✻1. Reading the port P8 register (address 001016) is switched to port P4 pin input level by the P8 function selection bit of the port control
register 2 (PCTL2).
Fig. 10 Port block diagram (1)
15
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
(9) Port P44
(10) Port P45
P4 output structure selection bit
Serial I/O enable bit
Receive enable bit
P45/TXD P-channel output disable bit
Serial I/O enable bit
Transmit enable bit
Direction
register
Direction
register
Data bus
Port latch
Port latch
Data bus
✻1
✻1
Serial I/O output
Serial I/O input
(11) Port P46
(12) Port P47
P4 output structure selection bit
Serial I/O mode selection bit
Serial I/O enable bit
Serialized IRQ enable bit
Serial I/O mode selection bit
Serial I/O
synchronous clock selection bit
Serial I/O enable bit
SRDY output enable bit
Serial I/O enable bit
Direction
register
Direction
register
Data bus
Port latch
Port latch
Data bus
Serial I/O ready output
✻1
CLKRUN output
Serial I/O clock output
Serial I/O external clock input
(14) Ports P54, P55
(13) Ports P50 to P53
P5i open drain selection bit
Direction
register
Data bus
Port latch
Data bus
Direction
register
Interrupt input
Port latch
Pulse output mode
Timer output
CNTR0, CNTR1 interrupt input
(15) Ports P56, P57
(16) Port P6
PWM0 (PWM1) output pin selection bit
PWM0 (PWM1) enable bit
Direction
register
Direction
register
Data bus
Port latch
Data bus
Port latch
A-D converter input
Analog input pin selection bit
PWM01 (PWM11) output
D-A converter output
D-A1 (D-A2) output enable bit
✻1. Reading the port P8 register (address 001016) is switched to port P4 pin input level by the P8 function selection bit of the port control
register 2 (PCTL2).
Fig. 11 Port block diagram (2)
16
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
(17) Ports P70 to P72
(18) Ports P73 to P75
Direction
register
Direction
register
Port latch
Data bus
Data bus
Port latch
✻2
✻2
(20) Port P77
(19) Port P76
I2C-BUS interface
enable bit
I2C-BUS interface
enable bit
Direction
register
Direction
register
Data bus
Data bus
Port latch
Port latch
SCL output
SDA output
SDA input
SCL input
✻3
(21) Ports P80 to P83
(22) Ports P84 to P86
LPC enable bit
LPC enable bit
Direction
register
Data bus
Interrupt input
✻3
Direction
register
Data bus
Port latch
LAD [3 : 0]
Port latch
LRESET
LCLK
LFRAME
(23) Port P87
SIRQ enable bit
Direction
register
Data bus
Port latch
IRQSER
✻2. The input level can be switched between CMOS compatible input level and TTL level by the P7 input level selection bit of the port
control register 2 (PCTL2).
Reading the port P8 direction register is switched to port P7 pin input level by the P8 function selection bit of the port control register 2
(PCTL2).
✻3. The input level can be switched between CMOS compatible input level and SMBUS level by the I2C-BUS interface pin input selection
bit of the I2C control register (SID).
Fig. 12 Port block diagram (3)
17
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
b7
b0
Port control register 1
(PCTL1: address 002E16)
P00–P03 output structure selection bit
0: CMOS
1: N-channel open-drain
P04–P07 output structure selection bit
0: CMOS
1: N-channel open-drain
P10–P13 output structure selection bit
0: CMOS
1: N-channel open-drain
P14–P17 output structure selection bit
0: CMOS
1: N-channel open-drain
P30–P33 pull-up control bit
0: No pull-up
1: Pull-up
P34–P37 pull-up control bit
0: No pull-up
1: Pull-up
PWM0 enable bit
0: PWM0 output disabled
1: PWM0 output enabled
PWM1 enable bit
0: PWM1 output disabled
1: PWM1 output enabled
b7
b0
Port control register 2
(PCTL2: address 002F16)
Not used (returns “0” when read)
P7 input level selection bit (P70-P75)
0: CMOS input level
1: TTL input level
P4 output structure selection bit (P42, P43, P44, P46)
0: CMOS
1: N-channel open-drain
P8 function selection bit
0: Port P8/Port P8 direction register
1: Port P4 input register/Port P7 input register
INT2, INT3, INT4 interrupt switch bit
0: INT20, INT30, INT40 interrupt
1: INT21, INT31, INT41 interrupt
Timer Y count source selection bit
0: f(XIN)/16 (f(XCIN)/16 in low-speed mode)
1: f(XCIN)
Oscillation stabilizing time set after STP instruction released bit
0: Automatic set “0116” to timer 1 and “FF16” to prescaler 12
1: No automatic set
Comparator reference input selection bit
0: P20/CMPREF input
1: Reference input fixed
Fig. 13 Structure of port I/O related registers (1)
18
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
b7
b0
Port P5 input register
(P5I: address 0FF816)
P50 input level bit
P51 input level bit
P52 input level bit
P53 input level bit
These bits directly show the pin input levels.
0: “L” level input
1: “H” level input
Not used (returns “0” when read)
b7
b0
Port control register 3
(PCTL3: address 0FF916)
P50 open drain selection bit
P51 open drain selection bit
P52 open drain selection bit
P53 open drain selection bit
0: CMOS
1: N-channel open drain
Not used (returns “0” when read)
Fig. 14 Structure of port I/O related registers (2)
19
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
INTERRUPTS
Interrupt Source Selection
Interrupts occur by 16 sources among 22 sources: thirteen external, nine internal, and one software.
Any of the following interrupt sources can be selected by the interrupt source selection register (INTSEL).
1. INT0 or Input buffer full
2. INT1 or Output buffer empty
3. Serial I/O receive or LRESET
4. Serial I/O transmission or SCLSDA
5. Timer 2 or INT5
6. CNTR0 or INT0
7. CNTR1 or INT1
8. A-D conversion or Key-on wake-up
Interrupt Control
Each interrupt is controlled by an interrupt request bit, an interrupt
enable bit, and the interrupt disable flag except for the software interrupt caused by the BRK instruction. An interrupt occurs when
both the corresponding interrupt request bit and interrupt enable
bit are “1” and the interrupt disable flag is “0”.
Interrupt enable bits can be set or cleared by software.
Interrupt request bits can be cleared by software, but cannot be
set by software.
The BRK instruction interrupt cannot be disabled with any flag or
bit. The I (interrupt disable) flag disables all interrupts except the
BRK instruction interrupt.
When several interrupts occur at the same time, the interrupts are
serviced according to the priority.
External Interrupt Pin Selection
The external interrupt sources of INT2, INT3, and INT4 can be selected from either input pin from INT20, INT30, INT40 or input pin
from INT21, INT31, INT41 by the INT2, INT3, INT4 interrupt switch
bit (bit 4 of PCTL2).
■ Notes
Interrupt Operation
By acceptance of an interrupt, the following operations are automatically performed:
1. The contents of the program counter and the processor status
register are automatically pushed onto the stack.
2. The interrupt disable flag is set and the corresponding interrupt
request bit is cleared.
3. The interrupt jump destination address is read from the vector
table and stored into the program counter.
When setting the followings, the interrupt request bit may be set to
“1”.
•When setting external interrupt active edge
Related register: Interrupt edge selection register (address
003A 16); Timer XY mode register (address
002316)
•When switching interrupt sources of an interrupt vector address
where two or more interrupt sources are allocated
Related register: Interrupt source selection register (address
003916)
•When setting input pin of external interrupts INT2, INT3 and INT4
Related register: INT2, INT3, INT4 interrupt switch bit of Port control register 2 (bit 4 of address 002F16)
When not requiring the interrupt occurrence synchronized with
these setting, take the following sequence.
➀ Set the corresponding interrupt enable bit to “0” (disabled).
➁ Set the active edge selection bit or the interrupt source selection bit to “1”.
➂ Set the corresponding interrupt request bit to “0” after 1 or more
instructions have been executed.
➃ Set the corresponding interrupt enable bit to “1” (enabled).
20
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 8 Interrupt vector addresses and priority
Interrupt Source
Reset (Note 2)
Priority
1
Vector Addresses (Note 1)
High
Low
FFFD16
FFFC16
INT0
2
FFFB16
FFFA16
Interrupt Request
Generating Conditions
At reset
Non-maskable
At detection of either rising or
falling edge of INT0 input
External interrupt
(active edge selectable)
Input buffer full
(IBF)
At input data bus buffer writing
INT1
At detection of either rising or
falling edge of INT1 input
Output buffer
empty (OBE)
Serial I/O
reception
3
4
FFF916
FFF716
FFF816
FFF616
LRESET
Serial I/O
transmission
5
FFF516
FFF416
6
7
8
FFF316
FFF116
FFEF16
FFF216
FFF016
FFEE16
9
FFED16
FFEC16
10
FFEB16
FFEA16
11
FFE916
FFE816
SCL, SDA
Timer X
Timer Y
Timer 1
Timer 2
INT5
CNTR0
INT0
CNTR1
INT1
I 2C
12
FFE716
FFE616
INT2
13
FFE516
FFE416
INT3
14
FFE316
FFE216
INT4
15
FFE116
FFE016
16
FFDF16
FFDE16
External interrupt
(active edge selectable)
At output data bus buffer reading
At completion of serial I/O data
reception
At falling edge of LRESET input
At completion of serial I/
Otransfer shift or when transmission buffer is empty
At detection of either rising or
falling edge of SCL or SDA
At timer X underflow
Valid when serial I/O is selected
External interrupt
Valid when serial I/O is selected
External interrupt
(active edge selectable)
At timer Y underflow
At timer 1 underflow
At timer 2 underflow
At detection of either rising or
falling edge of INT5 input
At detection of either rising or
falling edge of CNTR0 input
At detection of either rising or
falling edge of INT0 input
At detection of either rising or
falling edge of CNTR1 input
At detection of either rising or
falling edge of INT1 input
STP release timer underflow
External interrupt
(active edge selectable)
External interrupt
(active edge selectable)
External interrupt
(active edge selectable)
External interrupt
(active edge selectable)
External interrupt (falling valid)
At completion of data transfer
At detection of either rising or
falling edge of INT2 input
External interrupt
(active edge selectable)
At detection of either rising or
falling edge of INT3 input
At detection of either rising or
falling edge of INT4 input
External interrupt
(active edge selectable)
External interrupt
(active edge selectable)
At completion of A-D conversion
A-D converter
Key-on wake-up
BRK instruction
Remarks
17
FFDD16
FFDC16
At falling of port P3 (at input) input logical level AND
External interrupt (falling valid)
At BRK instruction execution
Non-maskable software interrupt
Notes 1: Vector addresses contain interrupt jump destination addresses.
2: Reset functions in the same way as an interrupt with the highest priority.
21
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Interrupt request bit
Interrupt enable bit
Interrupt disable flag (I)
BRK instruction
Reset
Interrupt request
Fig. 15 Interrupt control
b7
b0
Interrupt edge selection register
(INTEDGE : address 003A16)
INT0 active edge selection bit
INT1 active edge selection bit
Not used (returns “0” when read)
INT2 active edge selection bit
INT3 active edge selection bit
INT4 active edge selection bit
INT5 active edge selection bit
Not used (returns “0” when read)
b7
b0
0 : Falling edge active
1 : Rising edge active
Interrupt request register 1
(IREQ1 : address 003C16)
b7
INT0/input buffer full interrupt request
bit
INT1/output buffer empty interrupt
request bit
Serial I/O receive interrupt/LRESET
request bit
Serial I/O transmit/SCL, SDA interrupt
request bit
Timer X interrupt request bit
Timer Y interrupt request bit
Timer 1 interrupt request bit
Timer 2/INT5 interrupt request bit
b7
b0
Interrupt control register 1
(ICON1 : address 003E16)
INT0/input buffer full interrupt enable bit
INT1/output buffer empty interrupt enable
bit
Serial I/O receive interrupt/LRESET
enable bit
Serial I/O transmit/SCL, SDA interrupt
enable bit
Timer X interrupt enable bit
Timer Y interrupt enable bit
Timer 1 interrupt enable bit
Timer 2/INT5 interrupt enable bit
b0
Interrupt request register 2
(IREQ2 : address 003D16)
CNTR0/INT0 interrupt request bit
CNTR1/INT1 interrupt request bit
I2C interrupt request bit
INT2 interrupt request bit
INT3 interrupt request bit
INT4 interrupt request bit
AD converter/key-on wake-up interrupt
request bit
Not used (returns “0” when read)
0 : No interrupt request issued
1 : Interrupt request issued
b7
0
b0
Interrupt control register 2
(ICON2 : address 003F16)
CNTR0/INT0 interrupt enable bit
CNTR1/INT1 interrupt enable bit
I2C interrupt enable bit
INT2 interrupt enable bit
INT3 interrupt enable bit
INT4 interrupt enable bit
AD converter/key-on wake-up interrupt
enable bit
Not used (returns “0” when read)
(Do not write “1” to this bit)
0 : Interrupts disabled
1 : Interrupts enabled
Fig. 16 Structure of interrupt-related registers (1)
22
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
b7
b0
Interrupt source selection register
(INTSEL: address 003916)
INT0/input buffer full interrupt source selection bit
0 : INT0 interrupt
1 : Input buffer full interrupt
INT1/output buffer empty interrupt source selection bit
0 : INT1 interrupt
1 : Output buffer empty interrupt
Serial I/O receive/LRESET interrupt source selection bit
0 : Serial I/O receive
1 : LRESET interrupt
Serial I/O transmit/SCL, SDA interrupt source selection bit
0 : Serial I/O transmit interrupt
1 : SCL, SDA interrupt
Timer 2/INT5 interrupt source selection bit
0 : Timer 2 interrupt
1 : INT5 interrupt
CNTR0/INT0 interrupt source selection bit
0 : CNTR0 interrupt
1 : INT0 interrupt
CNTR1/INT1 interrupt source selection bit
0 : CNTR1 interrupt
1 : INT1 interrupt
AD converter/key-on wake-up interrupt source selection bit
0 : A-D converter interrupt
1 : Key-on wake-up interrupt
Fig. 17 Structure of interrupt-related registers (2)
23
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Key Input Interrupt (Key-on Wake Up)
A Key input interrupt request is generated by applying “L” level to
any pin of port P3 that have been set to input mode. In other
words, it is generated when the logical AND of all port P3 input
goes from “1” to “0”. An example of using a key input interrupt is
shown in Figure 18, where an interrupt request is generated by
pressing one of the keys consisted as an active-low key matrix
which inputs to ports P30–P33.
Port PXx
“L” level output
Port control register 1
Bit 5 = “0”
✻
Port P37
direction register = “1”
✻✻
Key input interrupt request
Port P37
latch
P37 output
Port P36
direction register = “1”
✻
✻✻
✻
✻✻
✻
✻✻
Port P36
latch
P36 output
Port P35
direction register = “1”
Port P35
latch
P35 output
Port P34
direction register = “1”
Port P34
latch
P34 output
✻
P33 input
✻
Port control register 1
Bit 4 = “1”
✻✻
Port P33
latch
✻✻
✻
Port P32
latch
Port P31
direction register = “0”
✻✻
P31 input
P30 input
Port P3 input circuit
Comparator circuit
Port P32
direction register = “0”
P32 input
✻
Port P33
direction register = “0”
Port P31
latch
Port P30
direction register = “0”
✻✻
Port P30
latch
✻ P-channel transistor for pull-up
✻✻ CMOS output buffer
Fig. 18 Connection example when using key input interrupt and port P3 block diagram
24
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
TIMERS
Timer 1 and Timer 2
The 3885 group has four timers: timer X, timer Y, timer 1, and
timer 2.
The division ratio of each timer or prescaler is given by 1/(n + 1),
where n is the value in the corresponding timer or prescaler latch.
All timers are count down structure. When the timer reaches
“0016”, an underflow occurs at the next count pulse and the corresponding timer latch is reloaded into the timer and the count is
continued. When a timer underflows, the interrupt request bit corresponding to that timer is set to “1”.
The count source of prescaler 12 is the oscillation frequency divided by 16. The output of prescaler 12 is counted by timer 1 and
timer 2, and a timer underflow sets the interrupt request bit.
Timer X and Timer Y
Timer X and Timer Y can each select one of four operating modes
by setting the timer XY mode register.
(1) Timer Mode
The timer counts f(XIN)/16.
(2) Pulse Output Mode
b7
b0
Timer XY mode register
(TM : address 002316)
Timer X operating mode bit
b1b0
0 0 : Timer mode
0 1 : Pulse output mode
1 0 : Event counter mode
1 1 : Pulse width measurement mode
CNTR0 active edge selection bit
0: Interrupt at falling edge
Count at rising edge in event
counter mode
1: Interrupt at rising edge
Count at falling edge in event
counter mode
Timer X count stop bit
0: Count start
1: Count stop
Timer Y operating mode bit
b5b4
0 0 : Timer mode
0 1 : Pulse output mode
1 0 : Event counter mode
1 1 : Pulse width measurement mode
CNTR1 active edge selection bit
0: Interrupt at falling edge
Count at rising edge in event
counter mode
1: Interrupt at rising edge
Count at falling edge in event
counter mode
Timer Y count stop bit
0: Count start
1: Count stop
Fig. 19 Structure of timer XY mode register
Timer X (or timer Y) counts f(XIN)/16. Whenever the contents of
the timer reach “00 16 ”, the signal output from the CNTR 0 (or
CNTR1) pin is inverted. If the CNTR0 (or CNTR1) active edge selection bit is “0”, output begins at “ H”.
If it is “1”, output starts at “L”. When using a timer in this mode, set
the corresponding port P54 ( or port P55) direction register to output mode.
(3) Event Counter Mode
Operation in event counter mode is the same as in timer mode,
except that the timer counts signals input through the CNTR0 or
CNTR1 pin.
When the CNTR0 (or CNTR1) active edge selection bit is “0”, the
rising edge of the CNTR0 (or CNTR1) pin is counted.
When the CNTR0 (or CNTR1) active edge selection bit is “1”, the
falling edge of the CNTR0 (or CNTR1) pin is counted.
(4) Pulse Width Measurement Mode
If the CNTR0 (or CNTR1) active edge selection bit is “0”, the timer
counts f(XIN)/16 while the CNTR0 (or CNTR1) pin is at “H”. If the
CNTR 0 (or CNTR 1 ) active edge selection bit is “1”, the timer
counts while the CNTR0 (or CNTR1) pin is at “L”.
The count can be stopped by setting “1” to the timer X (or timer Y)
count stop bit in any mode. The corresponding interrupt request
bit is set each time a timer overflows.
The count source for timer Y in the timer mode or the pulse output
mode can be selected from either f(XIN)/16 or f(XCIN) by the timer
Y count source selection bit of the port control register 2 (bit 5 of
PCTL2).
25
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Data bus
Divider
Oscillator
f(XIN)
Prescaler X latch (8)
1/16
Pulse width
measurement
mode
(f(XCIN) in low-speed mode)
Timer mode
Pulse output mode
Prescaler X (8)
CNTR0 active
edge selection
bit “0”
P54/CNTR0
Event
counter
mode
Timer X (8)
To timer X interrupt
request bit
Timer X count stop bit
To CNTR0 interrupt
request bit
“1”
CNTR0 active
edge selection “1”
bit
“0 ”
Q
Toggle flip-flop T
Q
R
Timer X latch write pulse
Pulse output mode
Port P54
latch
Port P54
direction register
Timer X latch (8)
Pulse output mode
Data bus
Oscillator
Divider
f(XIN)
Timer Y count source
selection bit
“0 ”
1/16
(f(XCIN) in low-speed mode)
Prescaler Y latch (8)
Oscillator
“1”
f(XCIN)
Prescaler Y (8)
CNTR1 active
edge selection
bit “0”
P55/CNTR1
“1 ”
Event
counter
mode
Port P55
direction register
Timer Y (8)
To timer Y interrupt
request bit
Timer Y count stop bit
To CNTR1 interrupt
request bit
CNTR1 active
edge selection “1”
bit
Q
Toggle flip-flop T
Q
Port P55
latch
Timer Y latch (8)
Pulse width
measureTimer mode
ment mode Pulse output mode
“0”
R
Timer Y latch write pulse
Pulse output mode
Pulse output mode
Data bus
Prescaler 12 latch (8)
Oscillator
f(XIN)
Timer 1 latch (8)
Timer 2 latch (8)
Timer 1 (8)
Timer 2 (8)
Divider
1/16
Prescaler 12 (8)
To timer 2 interrupt
request bit
(f(XCIN) in low-speed mode)
To timer 1 interrupt
request bit
Fig. 20 Block diagram of timer X, timer Y, timer 1, and timer 2
26
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
WATCHDOG TIMER
●Watchdog timer H count source selection bit operation
Bit 7 of WDTCON permits selecting a watchdog timer H count
source. When this bit is set to “0”, the count source becomes the
underflow signal of watchdog timer L. The detection time is set to
131.072 ms at f(XIN)=8 MHz and 32.768 s at f(XCIN)=32 kHz .
When this bit is set to “1”, the count source becomes the signal
divided by 16 for f(XIN) (or f(XCIN) in low speed mode). The detection time in this case is set to 512 µs at f(XIN)=8 MHz and 128 ms
at f(XCIN)=32 kHz . This bit is cleared to “0” after resetting.
The watchdog timer gives a mean of returning to the reset status
when a program cannot run on a normal loop (for example, because of a software run-away). The watchdog timer consists of an
8-bit watchdog timer L and an 8-bit watchdog timer H.
Basic Operation of Watchdog Timer
When any data is not written into the watchdog timer control register (WDTCON) after resetting, the watchdog timer is in the stop
state. The watchdog timer starts to count down by writing an optional value into the watchdog timer control register (WDTCON) and
an internal reset occurs at an underflow of the watchdog timer H.
Accordingly, programming is usually performed so that writing to
the watchdog timer control register (WDTCON) may be started before an underflow. When the watchdog timer control register
(WDTCON) is read, the values of the high-order 6 bits of the
watchdog timer H, STP instruction disable bit, and watchdog timer
H count source selection bit are read.
●STP instruction disable bit
Bit 6 of WDTCON permits disabling the STP instruction when the
watchdog timer is in operation.
When this bit is “0”, the STP instruction is enabled.
When this bit is “1”, the STP instruction is disabled.
When this bit is “1”, the STP instruction execution cause an internal reset. When this bit is set to “1”, it cannot be rewritten to “0” by
program. This bit is cleared to “0” after resetting.
Initial Value of Watchdog Timer
At reset or writing to the watchdog timer control register
(WDTCON), each watchdog timer H and L is set to “FF16”.
XCIN
“10”
Main clock division
ratio selection bits
(Note)
XIN
“FF16” is set when
watchdog timer
control register is
written to.
Data bus
“FF16” is set when
watchdog timer
control register is
written to.
“0”
Watchdog timer L (8)
1/16
“1”
“00”
“01”
Watchdog timer H (8)
Watchdog timer H count
source selection bit
STP instruction disable bit
STP instruction
Reset
circuit
RESET
Internal reset
Note: Either high-speed, middle-speed or low-speed mode is selected by bits 7 and 6 of the CPU mode register.
Fig. 21 Block diagram of Watchdog timer
b7
b0
Watchdog timer control register
(WDTCON : address 001E16)
Watchdog timer H (for read-out of high-order 6 bit)
STP instruction disable bit
0: STP instruction enabled
1: STP instruction disabled
Watchdog timer H count source selection bit
0: Watchdog timer L underflow
1: f(XIN)/16 or f(XCIN)/16
Fig. 22 Structure of Watchdog timer control register
27
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
PULSE WIDTH MODULATION (PWM)
OUTPUT CIRCUIT
The 3885 group has two PWM output circuits, PWM0 and PWM1,
with 14-bit resolution respectively. These can operate independently. When the oscillation frequency XIN is 8 MHz, the minimum
resolution bit width is 250 ns and the cycle period is 4096 µs. The
PWM timing generator supplies a PWM control signal based on a
signal that is the frequency of the XIN clock.
The following explanation assumes f(XIN) = 8 MHz.
Data Bus
Set to “1”
at write
PWM0L register (Address 003116)
bit 5
bit 7
bit 0
bit 0
bit 7
PWM0H register (Address 003016)
PWM0 latch (14 bits)
LSB
MSB
14
P30 latch
P30/PWM00
PWM0
14-bit PWM0 circuit
PWM0 enable bit
f(XIN)
(8MHz)
1/2
(4MHz)
PWM0
timing
generator
PWM0 output selection bit
PWM0 enable bit
(64 µs period)
(4096 µs period)
P30 direction register
P56 latch
P56/DA1/PWM01
PWM0 enable bit
PWM0 output selection bit
PWM0 enable bit
P56 direction register
Fig. 23 PWM block diagram (PWM0)
28
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Data Setup (PWM0)
this “H” duration by the contents of the low-order 6-bit data according to the rule in Table 9.
That is, only in the sub-period tm shown by Table 9 in the PWM
cycle period T = 64t, its “H” duration is lengthened to the minimum
resolution τ added to the length of other periods.
The PWM0 output pin also functions as port P30 or P5 6 . The
PWM0 output pin is selected from either P3 0 /PWM 00 or
P56/PWM01 by PWM0 output pin selection bit (bit 4 of ADCON).
The PWM0 output becomes enabled state by setting PWM0 enable bit (bit 6 of PCTL1). The high-order eight bits of output data
are set in the PWM0H register and the low-order six bits are set in
the PWM0L register.
PWM1 is set as the same way.
For example, if the high-order eight bits of the 14-bit data are 0316
and the low-order six bits are 0516, the length of the “H”-level output in sub-periods t8, t24, t32, t40, and t56 is 4 τ, and its length is 3
τ in all other sub-periods.
Time at the “H” level of each sub-period almost becomes equal,
because the time becomes length set in the high-order 8 bits or
becomes the value plus τ, and this sub-period t (= 64 µs, approximate 15.6 kHz) becomes cycle period approximately.
PWM Operation
The 14-bit PWM data is divided into the low-order six bits and the
high-order eight bits in the PWM latch.
The high-order eight bits of data determine how long an “H”-level
signal is output during each sub-period. There are 64 sub-periods
in each period, and each sub-period is 256 ✕ τ (64 µs) long. The
signal is “H” for a length equal to N times τ, where τ is the minimum resolution (250 ns).
“H” or “L” of the bit in the ADD part shown in Figure 24 is added to
Transfer From Register to Latch
Data written to the PWML register is transferred to the PWM latch
at each PWM period (every 4096 µs), and data written to the
PWMH register is transferred to the PWM latch at each sub-period
(every 64 µs). The signal which is output to the PWM output pin is
corresponding to the contents of this latch. When the PWML register is read, the latch contents are read. However, bit 7 of the
PWML register indicates whether the transfer to the PWM latch is
completed; the transfer is completed when bit 7 is “0” and it is not
done when bit 7 is “1”.
Table 9 Relationship between low-order 6 bits of data and
period set by the ADD bit
Low-order 6 bits of data (PWML)
0
0
0
0
0
0
1
0
0
0
0
0
1
0
0
0
0
0
1
0
0
0
0
0
1
0
0
0
0
0
1
0
0
0
0
LSB
0
1
0
0
0
0
0
Sub-periods tm Lengthened (m=0 to 63)
None
m=32
m=16, 48
m=8, 24, 40, 56
m=4, 12, 20, 28, 36, 44, 52, 60
m=2, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58, 62
m=1, 3, 5, 7, ................................................ ,57, 59, 61, 63
4096 µs
64 µs
64 µs
64 µs
64 µs
m=0
m=7
m=8
m=9
15.75 µs
15.75 µs
15.75 µs
16.0 µs
00111111
Pulse width modulation register H :
000101
Pulse width modulation register L :
Sub-periods where “H” pulse width is 16.0 µs :
Sub-periods where “H” pulse width is 15.75 µs :
15.75 µs
64 µs
m=63
15.75 µs
15.75 µs
m = 8, 24, 32, 40, 56
m = all other values
Fig. 24 PWM timing
29
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Data 6A16 stored at address 003016
PWM0H
register
5916
Data 7B16 stored at address 003016
6A16
7B16
Data 2416 stored at address 003116
PWM0L
register
1316
Bit 7 cleared after transfer
A416
Data 3516 stored at address 003116
2416
3516
Transfer from register to latch
PWM0 latch
(14bits)
165316
1A9316
Transfer from register to latch
B516
1AA416
1AA416
1EE416
1EF516
When bit 7 of PWM0L is 0, transfer
from register to latch is disabled.
T = 4096 µs
(64 ✕ 64 µs)
t = 64 µs
Example 1
6A
6B
6A
6B
6A
6B
6A
6B
6A
6B
6B
5
2
5
6B
6A
6B
6A
6B
6A
6B
6A
6B
6A
6B
6A
6B
6A
6B
6A
PWM0 output
1
low-order
6-bit output:
H
L
6A16, 2416
Example 2
5
5
5
5
6B16 ·············· 36 times
(107)
6A
6A 6A
6A
6B
6A
5
5
5
6A16 ············· 28 times
(106)
6B
6A
6B
6A
6A
6A
5
5
5
5
5
106 ✕ 64 + 36
6B
6A
6B
6A
6B
6A
6A
6A
6B
6A
6B
6A
6B
6A
PWM0 output
low-order
6-bit output:
H
L
6A16, 1816
4
6B16
3
··············
4
4
3
4
6A16 ······· 40 times
24 times
4
3
4
106 ✕ 64 + 24
t = 64 µs
(256 ✕ 0.25 µs)
Minimum resolution bit width τ = 0.25 µs
PWM output
2
6B
6A
69
68
67
·······
02
01
FF
FE
FD
FC
·······
97
96
ADD
8-bit
counter
02
01
00
69
68
67
·······
02
01
FF
FE
FD
FC
·······
97
96
ADD
The ADD
portions with
additional τ are
determined by
PWML.
Fig. 25 14-bit PWM timing (PWM0)
30
6A
95
H duration length specified by PWM0H
256 τ (64 µs), fixed
·······
02
01
00
95
·······
6A
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
(1) Clock Synchronous Serial I/O Mode
SERIAL I/O
Serial I/O
Clock synchronous serial I/O mode can be selected by setting the
serial I/O mode selection bit of the serial I/O control register (bit 6
of SIOCON) to “1”.
For clock synchronous serial I/O, the transmitter and the receiver
must use the same clock. When an internal clock is used, the
transfer starts by writing to the TB.
Serial I/O works as either clock synchronous serial I/O mode or
universal asynchronous receiver transmitter (UART) serial I/O
mode. A dedicated timer is also provided for baud rate generation.
Data bus
Receive buffer full flag (RBF)
Receive interrupt request (RI)
Receive shift register
P44/RXD
Address 001A16
Serial I/O control register
Address 001816
Receive buffer register
Shift clock
Clock control circuit
P46/SCLK
f(XIN)
Serial I/O synchronous
clock selection bit
BRG count source selection bit
(f(XCIN) in low-speed
mode)
Baud rate generator
1/4
Address 001C16
Frequency division ratio 1/(n+1)
1/4
P47/SRDY/CLKRUN
F/F
Clock control circuit
Falling-edge detector
Transmit shift completion flag (TSC)
Shift clock
P45/TXD
Transmit interrupt source selection bit
Transmit interrupt request (TI)
Transmit shift register
Transmit buffer register
Address 001816
Transmit buffer empty flag (TBE)
Serial I/O status register
Data bus
Fig. 26 Block diagram of clock synchronous serial I/O
Transfer shift clock
(1/2 to 1/2048 of the internal
clock, or an external clock)
TxD pin
D0
D1
D2
D3
D4
D5
D6
D7
RxD pin
D0
D1
D2
D3
D4
D5
D6
D7
SRDY pin
Write pulse to transmit buffer
register (TB)
TBE = 0
TSC = 1
TBE = 1
TSC = 0
RBF = 1
TSC = 1
Overrun error (OE)
detection
Notes 1: As the transmit interrupt (TI), which can be selected, either when the transmit buffer has emptied (TBE=1) or after the
transmit shift operation has ended (TSC=1), by setting the transmit interrupt source selection bit (TIC) of the serial I/O
control register.
2: If data is written to the transmit buffer register when TSC=0, the transmit clock is generated continuously and the next
serial data is output continuously from the TxD pin.
3: The receive interrupt (RI) is set when the receive buffer full flag (RBF) becomes “1” .
Fig. 27 Operation of clock synchronous serial I/O function
31
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
(2) Asynchronous Serial I/O (UART) Mode
Universal asynchronous transmitter receiver (UART) serial I/O
mode can be selected by clearing the serial I/O mode selection bit
of the serial I/O control register to “0”.
Eight serial data transfer formats can be selected, and the transfer
formats used by a transmitter and receiver must be identical.
Both the transmit and receive shift registers have a buffer, but the
two buffers assigned the same address. Since the shift register
cannot be written to or read from directly, transmit data is written
to the transmit buffer register, and receive data is read from the receive buffer register.
The transmit buffer register can also hold the next data to be
transmitted, and the receive buffer register can hold a character
while the next character is being received.
Data bus
Address
001816
P44/RXD
Serial I/O control register
Address
001A16
Receive buffer full flag (RBF)
Receive interrupt request (RI)
Receive buffer register
OE
Character length selection bit
ST detector
7 bits
Receive shift register
1/16
8 bits
PE FE
SP detector
Clock control circuit
UART control register
Address 001B16
Serial I/O synchronous clock selection bit
P46/SCLK
f(XIN)
(f(XCIN) in low-speed mode)
BRG count source selection bit Frequency division ratio 1/(n+1)
Baud rate generator
1/4
ST/SP/PA generator
1/16
P45/TXD
Transmit shift register
Transmit shift completion flag (TSC)
Transmit interrupt source selection bit
Transmit interrupt request (TI)
Character length selection bit
Transmit buffer register
Data bus
Fig. 28 Block diagram of UART mode
32
Transmit buffer empty flag (TBE)
Serial I/O status register Address 001916
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Transmit or receive clock
Transmit buffer write
signal
TBE=0
TSC=0
TBE=1
Serial output TXD pin
TBE=0
TSC=1✽
TBE=1
ST
D0
D1
SP
ST
D0
Receive buffer read
signal
SP
D1
✽
1 start bit
7 or 8 data bit
1 or 0 parity bit
1 or 2 stop bit (s)
Generated at 2nd bit in 2-stop-bit mode
RBF=0
RBF=1
Serial input RXD pin
ST
D0
D1
SP
RBF=1
ST
D0
D1
SP
Notes 1: Error flag detection occurs at the same time that the RBF flag becomes “1” (at 1st stop bit, during reception).
2: As the transmit interrupt (TI), when either the TBE or TSC flag becomes “1”, can be selected to occur depending on the setting of the transmit
interrupt source selection bit (TIC) of the serial I/O control register.
3: The receive interrupt (RI) is set when the RBF flag becomes “1”.
4: After data is written to the transmit buffer when TSC=1, 0.5 to 1.5 cycles of the data shift cycle is necessary until changing to TSC=0.
Fig. 29 Operation of UART mode function
[Serial I/O Control Register (SIOCON)] 001A16
The serial I/O control register consists of eight control bits for the
serial I/O function.
[UART Control Register (UARTCON)] 001B16
The UART control register consists of four control bits (bits 0 to 3)
which are valid in UART mode and set the data format of an data
transfer. The POFF bit (bit4) is always valid and define the output
structure of the P45/TXD pin.
[Serial I/O Status Register (SIOSTS)] 001916
The read-only serial I/O status register consists of seven flags
(bits 0 to 6) which indicate the operating status of the serial I/O
function and various errors.
Three of the flags (bits 4 to 6) are valid only in UART mode.
The receive buffer full flag (bit 1) is cleared to “0” when the receive
buffer register is read.
If there is an error, it is detected at the same time that data is
transferred from the receive shift register to the receive buffer register, and the receive buffer full flag is set. A write to the serial I/O
status register clears all the error flags OE, PE, FE, and SE (bit 3
to bit 6, respectively). Writing “0” to the serial I/O enable bit (SIOE,
bit 7 of SIDCON) also clears all the status flags, including the error flags.
Bits 0 to 6 of the serial I/O status register are initialized to “0” at reset, but if the transmit enable bit (TE, bit 4 of SIOCON) has been
set to “1”, the transmit shift completion flag (TSC, bit 2) and the
transmit buffer empty flag (TBE, bit 0) become “1”.
[Transmit Buffer Register/Receive Buffer
Register (TB/RB)] 001816
The transmit buffer register and the receive buffer register are located at the same address. The transmit buffer is write-only and
the receive buffer is read-only. If a character length is 7 bits, the
MSB data stored in the receive buffer is “0”.
[Baud Rate Generator (BRG)] 001C16
The baud rate generator determines the baud rate for serial transfer.
The baud rate generator divides the frequency of the count source
by 1/(n + 1), where n is the value written to the baud rate generator.
■ Notes
When setting the transmit enable bit to “1”, the serial I/O transmit
interrupt request bit is automatically set to “1”. When not requiring
the interrupt occurrence synchronized with the transmission enabled, take the following sequence.
➀ Set the serial I/O transmit interrupt enable bit to “0” (disabled).
➁ Set the transmit enable bit to “1”.
➂ Set the serial I/O transmit interrupt request bit to “0” after 1 or
more instructions have been executed.
➃ Set the serial I/O transmit interrupt enable bit to “1” (enabled).
33
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
b7
b7
b0
b0
Serial I/O status register
(SIOSTS : address 001916)
b0
Serial I/O control register
(SIOCON : address 001A16)
Transmit buffer empty flag (TBE)
0: Buffer full
1: Buffer empty
BRG count source selection bit (CSS)
0: f(XIN) (f(XCIN) in low-speed mode)
1: f(XIN)/4 (f(XCIN)/4 in low-speed mode)
Receive buffer full flag (RBF)
0: Buffer empty
1: Buffer full
Transmit shift completion flag (TSC)
0: Transmit shift in progress
1: Transmit shift completed
Serial I/O synchronous clock selection bit (SCS)
0: BRG output divided by 4 when clock synchronous
serial I/O is selected, BRG output divided by 16
when UART is selected.
1: External clock input when clock synchronous serial
I/O is selected, external clock input divided by 16
when UART is selected.
Overrun error flag (OE)
0: No error
1: Overrun error
SRDY output enable bit (SRDY)
0: P47 pin operates as ordinary I/O pin
1: P47 pin operates as SRDY output pin
Parity error flag (PE)
0: No error
1: Parity error
Transmit interrupt source selection bit (TIC)
0: Interrupt when transmit buffer has emptied
1: Interrupt when transmit shift operation is completed
Framing error flag (FE)
0: No error
1: Framing error
Transmit enable bit (TE)
0: Transmit disabled
1: Transmit enabled
Summing error flag (SE)
0: (OE) U (PE) U (FE)=0
1: (OE) U (PE) U (FE)=1
Receive enable bit (RE)
0: Receive disabled
1: Receive enabled
Not used (returns “1” when read)
Serial I/O mode selection bit (SIOM)
0: Clock asynchronous (UART) serial I/O
1: Clock synchronous serial I/O
UART control register
(UARTCON : address 001B16)
Character length selection bit (CHAS)
0: 8 bits
1: 7 bits
Parity enable bit (PARE)
0: Parity checking disabled
1: Parity checking enabled
Parity selection bit (PARS)
0: Even parity
1: Odd parity
Stop bit length selection bit (STPS)
0: 1 stop bit
1: 2 stop bits
P45/TXD P-channel output disable bit (POFF)
0: CMOS output (in output mode)
1: N-channel open drain output (in output mode)
Not used (return “1” when read)
Fig. 30 Structure of serial I/O control registers
34
b7
Serial I/O enable bit (SIOE)
0: Serial I/O disabled
(pins P44 to P47 operate as ordinary I/O pins)
1: Serial I/O enabled
(pins P44 to P47 operate as serial I/O pins)
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MULTI-MASTER I2C-BUS INTERFACE
Table 10 Multi-master I2C-BUS interface functions
The multi-master I2C-BUS interface is a serial communications circuit, conforming to the Philips I2C-BUS data transfer format. This
interface, offering both arbitration lost detection and a synchronous
functions, is useful for the multi-master serial communications.
Figure 31 shows a block diagram of the multi-master I2C-BUS interface and Table 10 lists the multi-master I 2 C-BUS interface
functions.
This multi-master I2C-BUS interface consists of the I2C address
register, the I 2C data shift register, the I2C clock control register,
the I2C control register, the I2C status register, the I2C start/stop
condition control register and other control circuits.
When using the multi-master I2 C-BUS interface, set 1 MHz or
more to system clock φ.
b7
Interrupt
generating
circuit
Interrupt request signal
(SCLSDAIRQ)
Item
Format
Communication mode
SCL clock frequency
Function
In conformity with Philips I2C-BUS
standard:
10-bit addressing format
7-bit addressing format
High-speed clock mode
Standard clock mode
In conformity with Philips I2C-BUS
standard:
Master transmission
Master reception
Slave transmission
Slave reception
16.1 kHz to 400 kHz (at φ = 4 MHz)
System clock φ = f(XIN)/2 (high-speed mode)
φ = f(XIN)/8 (middle-speed mode)
I2C address register
SAD6 SAD5 SAD4 SAD3 SAD2 SAD1 SAD0
b0
Interrupt
generating
circuit
RWB
S0D
Interrupt request signal
(I2CIRQ)
Address comparator
Serial data
(SDA)
Noise
elimination
circuit
Data
control
circuit
b0
b7
I2C data shift register
b7
b0
S0
AL AAS AD0 LRB
MST TRX BB PIN
S2D
STSP
SIS SIP SSC4SSC3 SSC2 SSC1 SSC0
SEL
AL
circuit
I2C status register
S1
I2C start/stop condition
control register
Internal data bus
BB
circuit
Serial
clock
(SCL)
Noise
elimination
circuit
Clock
control
circuit
b7
b0
FAST
ACK ACK MODE CCR4 CCR3 CCR2 CCR1 CCR0
BIT
I2C clock control register
S1D
b0
b7
TISS
CLK
STP
10BIT
SAD
ALS ES0 BC2 BC1 BC0
S2
I2C clock control register
Clock division
Stop selection
System clock (φ)
Bit counter
Fig. 31 Block diagram of multi-master I2C-BUS interface
✽ : Purchase of MITSUBISHI ELECTRIC CORPORATIONS I2C components conveys a license under the Philips I2C Patent Rights to use these components
an I2C system, provided that the system conforms to the I2C Standard Specification as defined by Philips.
35
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[I2C Data Shift Register (S0)] 001216
The I2C data shift register (S0) is an 8-bit shift register to store receive data and write transmit data.
When transmit data is written into this register, it is transferred to
the outside from bit 7 in synchronization with the SCL clock, and
each time one-bit data is output, the data of this register are
shifted by one bit to the left. When data is received, it is input to
this register from bit 0 in synchronization with the SCL clock, and
each time one-bit data is input, the data of this register are shifted
by one bit to the left. The minimum 2 cycles of φ are required from
the rising of the SCL clock until input to this register.
The I2C data shift register is in a write enable status only when the
I2C-BUS interface enable bit (ES0 bit : bit 3 S1D) of the I2C control register is “1”. The bit counter is reset by a write instruction to
the I2C data shift register. When both the ES0 bit and the MST bit
of the I2C status register (S1) are “1”, the SCL is output by a write
instruction to the I2C data shift register. Reading data from the I2C
data shift register is always enabled regardless of the ES0 bit
value.
[I2C Address Register (S0D)] 001316
The I2C address register (S0D) consists of a 7-bit slave address and
_______
a read/write bit. In the addressing mode, the slave address written in
this register is compared with the address data to be received immediately after the START condition is detected.
_________
•Bit 0: Read/write bit (RWB)
This is not used in the 7-bit addressing mode. In the 10-bit addressing mode, the first address data to be received is compared
with the contents (SAD6 to SAD0 + RWB) of the I2C address register.
The RWB bit is cleared to “0” automatically when the stop condition is detected.
•Bits 1 to 7: Slave address (SAD0–SAD6)
These bits store slave addresses. Regardless of the 7-bit addressing mode and the 10-bit addressing mode, the address data
transmitted from the master is compared these bits.
36
b7
b0
SAD6 SAD5 SAD4 SAD3 SAD2 SAD1 SAD0 RWB
I2C address register
(S0D: address 001316)
Read/write bit
Slave address
Fig. 32 Structure of I2C address register
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[I2C Clock Control Register (S2)] 001616
I 2C
Note: Do not write data into the
clock control register during transfer. If
data is written during transfer, the I2C clock generator is reset, so
that data cannot be transferred normally.
I2C clock control register
(S2 : address 001616)
SCL frequency control
bits
Refer to Table 11.
SCL mode specification bit
0 : Standard clock mode
1 : High-speed clock
mode
ACK bit
0 : ACK is returned.
1 : ACK is not
returned.
ACK clock bit
0 : No ACK clock
1 : ACK clock
Fig. 33 Structure of I2C clock control register
Table 11 Set values of I2 C clock control register and S CL
frequency
Setting value of
CCR4–CCR0
CCR4 CCR3 CCR2 CCR1 CCR0
SCL frequency
(at φ = 4 MHz, unit : kHz) (Note 1)
Standard clock High-speed clock
mode
mode
0
0
0
Setting disabled
Setting disabled
0
0
0
1
Setting disabled
Setting disabled
0
0
0
1
0
Setting disabled
Setting disabled
0
0
0
1
1
– (Note 2)
333
0
0
1
0
0
– (Note 2)
250
0
0
1
0
1
100
400 (Note 3)
0
0
1
1
0
83.3
166
1000/CCR value
(Note 3)
…
0
0
…
0
…
•Bit 7: ACK clock bit (ACK)
This bit specifies the mode of acknowledgment which is an acknowledgment response of data transfer. When this bit is set to
“0”, the no ACK clock mode is selected. In this case, no ACK clock
occurs after data transmission. When the bit is set to “1”, the ACK
clock mode is selected and the master generates an ACK clock
each completion of each 1-byte data transfer. The device for
transmitting address data and control data releases the SDA at the
occurrence of an ACK clock (makes S DA “H”) and receives the
ACK bit generated by the data receiving device.
b0
ACK FAST
BIT MODE CCR4 CCR3 CCR2 CCR1 CCR0
…
✽ACK clock: Clock for acknowledgment
b7
ACK
…
The I2C clock control register (S2) is used to set ACK control, SCL
mode and SCL frequency.
•Bits 0 to 4: SCL frequency control bits (CCR0–CCR4)
These bits control the SCL frequency. Refer to Table 11.
•Bit 5: SCL mode specification bit (FAST MODE)
This bit specifies the SCL mode. When this bit is set to “0”, the
standard clock mode is selected. When the bit is set to “1”, the
high-speed clock mode is selected.
When connecting the bus of the high-speed mode I2C bus standard (maximum 400 kbits/s), use 8 MHz or more oscillation
frequency f(XIN) and high-speed mode (2 division main clock).
•Bit 6: ACK bit (ACK BIT)
This bit sets the SDA status when an ACK clock✽ is generated.
When this bit is set to “0”, the ACK return mode is selected and
SDA goes to “L” at the occurrence of an ACK clock. When the bit is
set to “1”, the ACK non-return mode is selected. The SDA is held in
the “H” status at the occurrence of an ACK clock.
However, when the slave address matches with the address data
in the reception of address data at ACK BIT = “0”, the SDA is automatically made “L” (ACK is returned). If there is a unmatch
between the slave address and the address data, the SDA is automatically made “H” (ACK is not returned).
500/CCR value
(Note 3)
1
1
1
0
1
17.2
34.5
1
1
1
1
0
16.6
33.3
1
1
1
1
1
16.1
32.3
Notes 1: Duty of SCL clock output is 50 %. The duty becomes 35 to 45 %
only when the high-speed clock mode is selected and CCR value
= 5 (400 kHz, at φ = 4 MHz). “H” duration of the clock fluctuates
from –4 to +2 cycles of φ in the standard clock mode, and fluctuates from –2 to +2 cycles of φ in the high-speed clock mode. In
the case of negative fluctuation, the frequency does not increase
because “L” duration is extended instead of “H” duration reduction.
These are value when SCL clock synchronization by the synchronous function is not performed. CCR value is the decimal
notation value of the SCL frequency control bits CCR4 to CCR0.
2: Each value of SCL frequency exceeds the limit at φ = 4 MHz or
more. When using these setting value, use φ of 4 MHz or less.
3: The data formula of SCL frequency is described below:
φ/(8 ✕ CCR value) Standard clock mode
φ/(4 ✕ CCR value) High-speed clock mode (CCR value ≠ 5)
φ/(2 ✕ CCR value) High-speed clock mode (CCR value = 5)
Do not set 0 to 2 as CCR value regardless of φ frequency.
Set 100 kHz (max.) in the standard clock mode and 400 kHz
(max.) in the high-speed clock mode to the SCL frequency by setting the SCL frequency control bits CCR4 to CCR0.
37
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[I2C Control Register (S1D)] 001516
The I2C control register (S1D) controls data communication format.
•Bits 0 to 2: Bit counter (BC0–BC2)
These bits decide the number of bits for the next 1-byte data to be
transmitted. The I2C interrupt request signal occurs immediately
after the number of count specified with these bits (ACK clock is
added to the number of count when ACK clock is selected by ACK
bit (bit 7 of S2)) have been transferred, and BC0 to BC2 are returned to “0002”.
Also when a START condition is received, these bits become
“0002” and the address data is always transmitted and received in
8 bits.
•Bit 3: I2C interface enable bit (ES0)
This bit enables to use the multi-master I2C BUS interface. When
this bit is set to “0”, the use disable status is provided, so that the
SDA and the SCL become high-impedance. When the bit is set to
“1”, use of the interface is enabled.
When ES0 = “0”, the following is performed.
• PIN = “1”, BB = “0” and AL = “0” are set (which are bits of the I2C
status register at S1 ).
• Writing data to the I2C data shift register (S0) is disabled.
•Bit 4: Data format selection bit (ALS)
This bit decides whether or not to recognize slave addresses.
When this bit is set to “0”, the addressing format is selected, so
that address data is recognized. When a match is found between
a slave address and address data as a result of comparison or
when a general call (refer to “I 2C Status Register”, bit 1) is received, transfer processing can be performed. When this bit is set
to “1”, the free data format is selected, so that slave addresses are
not recognized.
•Bit 5: Addressing format selection bit (10BIT SAD)
This bit selects a slave address specification format. When this bit
is set to “0”, the 7-bit addressing format is selected. In this case,
only the high-order 7 bits (slave address) of the I2C address register (S0D) are compared with address data. When this bit is set to
“1”, the 10-bit addressing format is selected, and all the bits of the
I2C address register are compared with address data.
•Bit 6: System clock stop selection bit (CLKSTP)
When executing the WIT or STP instruction, this bit selects the
condition of system clock provided to the multi-master I2C-BUS interface. When this bit is set to “0”, system clock and operation of
the multi-master I2C-BUS interface stop by executing the WIT or
STP instruction.
When this bit is set to “1”, system clock and operation of the multimaster I 2 C-BUS interface do not stop even when the WIT
instruction is executed.
When the system clock stop selection bit is “1”, do not execute the
STP instruction.
•Bit 7: I2C-BUS interface pin input level selection bit
This bit selects the input level of the SCL and SDA pins of the multimaster I2C-BUS interface.
38
b7
TISS
b0
CLK 10 BIT
ALS ES0 BC2 BC1 BC0
STP SAD
I2C control register
(S1D : address 001516)
Bit counter (Number of
transmit/receive bits)
b2 b1 b0
0 0 0 : 8
0 0 1 : 7
0 1 0 : 6
0 1 1 : 5
1 0 0 : 4
1 0 1 : 3
1 1 0 : 2
1 1 1 : 1
I2C-BUS interface
enable bit
0 : Disabled
1 : Enabled
Data format selection bit
0 : Addressing format
1 : Free data format
Addressing format selection bit
0 : 7-bit addressing format
1 : 10-bit addressing format
System clock stop selection bit
0 : System clock stop
when executing WIT
or STP instruction
1 : Not system clock
stop when executing
WIT instruction
(Do not use the STP
instruction.)
I2C-BUS interface pin input
level selection bit
0 : CMOS input
1 : SMBUS input
Fig. 34 Structure of I2C control register
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[I2C Status Register (S1)] 001416
The I2C status register (S1) controls the I2C-BUS interface status.
The low-order 4 bits are read-only bits and the high-order 4 bits
can be read out and written to.
Set “00002” to the low-order 4 bits, because these bits become the
reserved bits at writing.
•Bit 0: Last receive bit (LRB)
This bit stores the last bit value of received data and can also be
used for ACK receive confirmation. If ACK is returned when an
ACK clock occurs, the LRB bit is set to “0”. If ACK is not returned,
this bit is set to “1”. Except in the ACK mode, the last bit value of
received data is input. The state of this bit is changed from “1” to
“0” by executing a write instruction to the I2C data shift register
(S0).
•Bit 1: General call detecting flag (AD0)
When the ALS bit is “0”, this bit is set to “1” when a general call✽
whose address data is all “0” is received in the slave mode. By a
general call of the master device, every slave device receives control data after the general call. The AD0 bit is set to “0” by
detecting the STOP condition or START condition, or reset.
✽General call: The master transmits the general call address “00 16” to all
slaves.
•Bit 2: Slave address comparison flag (AAS)
This flag indicates a comparison result of address data when the
ALS bit is “0”.
➀ In the slave receive mode, when the 7-bit addressing format is
selected, this bit is set to “1” in one of the following conditions:
• The address data immediately after occurrence of a START
condition agrees with the slave address stored in the high-order 7 bits of the I2C address register (S0D).
• A general call is received.
➁ In the slave reception mode, when the 10-bit addressing format
is selected, this bit is set to “1” with the following condition:
• When the address data is compared with the I2C address register (8 bits consisting of slave address and RWB bit), the first
bytes agree.
➂ This bit is set to “0” by executing a write instruction to the I 2C
data shift register (S0) when ES0 is set to “1” or reset.
•Bit 3: Arbitration lost✽ detecting flag (AL)
In the master transmission mode, when the SDA is made “L” by
any other device, arbitration is judged to have been lost, so that
this bit is set to “1”. At the same time, the TRX bit is set to “0”, so
that immediately after transmission of the byte whose arbitration
was lost is completed, the MST bit is set to “0”. The arbitration lost
can be detected only in the master transmission mode. When arbitration is lost during slave address transmission, the TRX bit is
set to “0” and the reception mode is set. Consequently, it becomes
possible to detect the agreement of its own slave address and address data transmitted by another master device.
•Bit 4: SCL pin low hold bit (PIN)
This bit generates an interrupt request signal. Each time 1-byte
data is transmitted, the PIN bit changes from “1” to “0”. At the
same time, an interrupt request signal occurs to the CPU. The PIN
bit is set to “0” in synchronization with a falling of the last clock (including the ACK clock) of an internal clock and an interrupt
request signal occurs in synchronization with a falling of the PIN
bit. When the PIN bit is “0”, the SCL is kept in the “0” state and
clock generation is disabled. Figure 42 shows an interrupt request
signal generating timing chart.
The PIN bit is set to “1” in one of the following conditions:
• Executing a write instruction to the I2C data shift register (S0).
(This is the only condition which the prohibition of the internal
clock is released and data can be communicated except for the
start condition detection.)
• When the ES0 bit is “0”
• At reset
• When writing “1” to the PIN bit by software
The conditions in which the PIN bit is set to “0” are shown below:
• Immediately after completion of 1-byte data transmission (including when arbitration lost is detected)
• Immediately after completion of 1-byte data reception
• In the slave reception mode, with ALS = “0” and immediately after completion of slave address agreement or general call
address reception
• In the slave reception mode, with ALS = “1” and immediately after completion of address data reception
•Bit 5: Bus busy flag (BB)
This bit indicates the status of use of the bus system. When this
bit is set to “0”, this bus system is not busy and a START condition
can be generated. The BB flag is set/reset by the SCL, SDA pins input signal regardless of master/slave. This flag is set to “1” by
detecting the start condition, and is set to “0” by detecting the stop
condition. The condition of these detecting is set by the start/stop
condition setting bits (SSC4–SSC0) of S2D. When the ES0 bit (bit
3 of S1D) is “0” or reset, the BB flag is set to “0”.
For the writing function to the BB flag, refer to the sections
“START Condition Generating Method” and “STOP Condition Generating Method” described later.
✽Arbitration lost :The status in which communication as a master is disabled.
39
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
•Bit 6: Communication mode specification bit
(transfer direction specification bit: TRX)
This bit decides a direction of transfer for data communication.
When this bit is “0”, the reception mode is selected and the data of
a transmitting device is received. When the bit is “1”, the transmission mode is selected and address data and control data are
output onto the SDA in synchronization with the clock generated on
the SCL.
This bit is set/reset by software and hardware. About set/reset by
hardware is described below. This bit is set to “1” by hardware
when all the following conditions are satisfied:
• When ALS is “0”
• In the slave reception mode or the slave transmission mode
___
• When the R/W bit reception is “1”
This bit is set to “0” in one of the following conditions:
• When arbitration lost is detected.
• When a STOP condition is detected.
• When writing “1” to this bit by software is invalid by the START
condition duplication preventing function (Note).
• With MST = “0” and when a START condition is detected.
• With MST = “0” and when ACK non-return is detected.
• At reset
•Bit 7: Communication mode specification bit
(master/slave specification bit: MST)
This bit is used for master/slave specification for data communication. When this bit is “0”, the slave is specified, so that a START
condition and a STOP condition generated by the master are received, and data communication is performed in synchronization
with the clock generated by the master. When this bit is “1”, the
master is specified and a START condition and a STOP condition
are generated. Additionally, the clocks required for data communication are generated on the SCL.
This bit is set to “0” in one of the following conditions.
• Immediately after completion of 1-byte data transfer when arbitration lost is detected
• When a STOP condition is detected.
• Writing “1” to this bit by software is invalid by the START condition duplication preventing function (Note).
• At reset
Note: START condition duplication preventing function
The MST, TRX, and BB bits is set to “1” at the same time after confirming that the BB flag is “0” in the procedure of a START condition
occurrence. However, when a START condition by another master
device occurs and the BB flag is set to “1” immediately after the contents of the BB flag is confirmed, the START condition duplication
preventing function makes the writing to the MST and TRX bits invalid. The duplication preventing function becomes valid from the
rising of the BB flag to reception completion of slave address.
b7
b0
MST TRX BB PIN AL AAS AD0 LRB
I2C status register
(S1 : address 001416)
Last receive bit (Note)
0 : Last bit = “0”
1 : Last bit = “1”
General call detecting flag
(Note)
0 : No general call detected
1 : General call detected
Slave address comparison flag
(Note)
0 : Address disagreement
1 : Address agreement
Arbitration lost detecting flag
(Note)
0 : Not detected
1 : Detected
SCL pin low hold bit
0 : low hold
1 : release
Bus busy flag
0 : Bus free
1 : Bus busy
Communication mode
specification bits
00 : Slave receive mode
01 : Slave transmit mode
10 : Master receive mode
11 : Master transmit mode
Note: These bit and flags can be read out but cannot
be written.
Write “0” to these bits at writing.
Fig. 35 Structure of I2C status register
SCL
PIN
I2CIRQ
Fig. 36 Interrupt request signal generating timing
40
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
START Condition Generating Method
START/STOP Condition Detecting Operation
When writing “1” to the MST, TRX, and BB bits of the I2C status
register (S1) at the same time after writing the slave address to
the I2C data shift register (S0) with the condition in which the ES0
bit of the I 2C control register (S1D) and the BB flag are “0”, a
START condition occurs. After that, the bit counter becomes
“0002” and an SCL for 1 byte is output. The START condition generating timing is different in the standard clock mode and the
high-speed clock mode. Refer to Figure 37, the START condition
generating timing diagram, and Table 12, the START condition
generating timing table.
The START/STOP condition detection operations are shown in
Figures 39, 40, and Table 14. The START/STOP condition is set
by the START/STOP condition set bit.
The START/STOP condition can be detected only when the input
signal of the SCL and SDA pins satisfy three conditions: SCL release time, setup time, and hold time (see Table 14).
The BB flag is set to “1” by detecting the START condition and is
reset to “0” by detecting the STOP condition.
The BB flag set/reset timing is different in the standard clock mode
and the high-speed clock mode. Refer to Table 14, the BB flag set/
reset time.
Note: When a STOP condition is detected in the slave mode (MST = 0), an
interrupt request signal “I2CIRQ” occurs to the CPU.
I2C status register
write signal
SC L
Setup
time
SDA
SCL release time
Hold time
SCL
Fig. 37 START condition generating timing diagram
Table 12 START condition generating timing table
Item
Setup
time
Hold
time
START/STOP condition
generating selection bit
Standard
clock mode
High-speed
clock mode
“0”
“1”
“0”
“1”
5.0 µs (20 cycles)
13.0 µs (52 cycles)
5.0 µs (20 cycles)
13.0 µs (52 cycles)
2.5 µs (10 cycles)
6.5 µs (26 cycles)
2.5 µs (10 cycles)
6.5 µs (26 cycles)
Note: Absolute time at φ = 4 MHz. The value in parentheses denotes the
number of φ cycles.
STOP Condition Generating Method
When the ES0 bit of the I2C control register (S1D) is “1”, write “1”
to the MST and TRX bits, and write “0” to the BB bit of the I2C status register (S1) simultaneously. Then a STOP condition occurs.
The STOP condition generating timing is different in the standard
clock mode and the high-speed clock mode. Refer to Figure 38,
the STOP condition generating timing diagram, and Table 13, the
STOP condition generating timing table.
SDA
SCL
SDA
Fig. 39 START condition detecting timing diagram
SCL release time
SCL
SDA
BB flag
Setup
time
Hold time
BB flag
reset
time
Fig. 40 STOP condition detecting timing diagram
Table 14 START condition/STOP condition detecting conditions
Standard clock mode
SCL release time
SSC value + 1 cycle (6.25 µs)
Setup time
SSC value + 1 cycle < 4.0 µs (3.25 µs)
2
SSC value
cycle < 4.0 µs (3.0 µs)
2
BB flag set/
reset time
Setup
time
Hold time
BB flag
reset
time
BB flag
Hold time
I2C status register
write signal
Setup
time
SSC value –1 + 2 cycles (3.375 µs)
2
High-speed clock mode
4 cycles (1.0 µs)
2 cycles (1.0 µs)
2 cycles (0.5 µs)
3.5 cycles (0.875 µs)
Note: Unit : Cycle number of system clock φ
SSC value is the decimal notation value of the START/STOP condition set bits SSC4 to SSC0. Do not set “0” or an odd number to SSC
value. The value in parentheses is an example when the I2C START/
STOP condition control register is set to “1816” at φ = 4 MHz.
Hold time
Fig. 38 STOP condition generating timing diagram
Table 13 STOP condition generating timing table
Item
Setup
time
Hold
time
START/STOP condition
generating selection bit
“0”
“1”
“0”
“1”
Standard
clock mode
5.5 µs (22 cycles)
13.5 µs (54 cycles)
5.5 µs (22 cycles)
13.5 µs (54 cycles)
High-speed
clock mode
3.0 µs (12 cycles)
7.0 µs (28 cycles)
3.0 µs (12 cycles)
7.0 µs (28 cycles)
Note: Absolute time at φ = 4 MHz. The value in parentheses denotes the
number of φ cycles.
41
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[I2C START/STOP Condition Control Register
(S2D)] 001716
The I2C START/STOP condition control register (S2D) controls
START/STOP condition detection.
•Bits 0 to 4: START/STOP condition set bits (SSC4–SSC0)
SCL release time, setup time, and hold time change the detection
condition by value of the main clock divide ratio selection bit and
the oscillation frequency f(XIN) because these time are measured
by the internal system clock. Accordingly, set the proper value to
the START/STOP condition set bits (SSC4 to SSC0) in considered
of the system clock frequency. Refer to Table 14.
Do not set “000002” or an odd number to the START/STOP condition set bits (SSC4 to SSC0).
Refer to Table 15, the recommended set value to START/STOP
condition set bits (SSC4–SSC0) for each oscillation frequency.
•Bit 5: SCL/SDA interrupt pin polarity selection bit (SIP)
An interrupt can occur when detecting the falling or rising edge of
the SCL or SDA pin. This bit selects the polarity of the SCL or SDA
pin interrupt pin.
•Bit 6: SCL/SDA interrupt pin selection bit (SIS)
This bit selects the pin of which interrupt becomes valid between
the SCL pin and the SDA pin.
Note: When changing the setting of the S CL/SDA interrupt pin polarity selection bit, the SCL /S DA interrupt pin selection bit, or the I 2C-BUS
interface enable bit ES0, the SCL/S DA interrupt request bit may be
set. When selecting the SCL/SDA interrupt source, disable the interrupt before the SCL/SDA interrupt pin polarity selection bit, the SCL/
SDA interrupt pin selection bit, or the I 2C-BUS interface enable bit
ES0 is set. Reset the request bit to “0” after setting these bits, and
enable the interrupt.
•Bit 7: START/STOP condition generating selection bit
(STSPSEL)
Setup/Hold time when the START/STOP condition is generated
can be selected.
Cycle number of system clock becomes standard for setup/hold
time. Additionally, setup/hold time is different between the START
condition and the STP condition. (Refer to Tables 12 and 13.) Set
“1” to this bit when the system clock frequency is 4 MHz or more.
Address Data Communication
There are two address data communication formats, namely, 7-bit
addressing format and 10-bit addressing format. The respective
address communication formats are described below.
➀ 7-bit addressing format
To adapt the 7-bit addressing format, set the 10BIT SAD bit of
the I2C control register (S1D) to “0”. The first 7-bit address data
transmitted from the master is compared with the high-order 7bit slave address stored in the I2C address register (S0D). At
the time of this comparison, address comparison of the RWB bit
of the I2C address register (S0D) is not performed. For the data
transmission format when the 7-bit addressing format is selected, refer to Figure 42, (1) and (2).
42
➁ 10-bit addressing format
To adapt the 10-bit addressing format, set the 10BIT SAD bit of
the I2C control register (S1D) to “1”. An address comparison is
performed between the first-byte address data transmitted from
the master and the 8-bit slave address stored in the I 2C address register (S0). At the time of this comparison, an address
comparison between the RWB bit of the I2C address register
(S0) and the R/W bit which is the last bit of the address data
transmitted from the master is made. In the 10-bit addressing
mode, the RWB bit which is the last bit of the address data not
only specifies the direction of communication for control data,
but also is processed as an address data bit.
When the first-byte address data agree with the slave address,
the AAS bit of the I2C status register (S1) is set to “1”. After the
second-byte address data is stored into the I2C data shift register (S0), perform an address comparison between the
second-byte data and the slave address by software. When the
address data of the 2 bytes agree with the slave address, set
the RWB bit of the I2C address register (S0D) to “1” by software. This processing can make the 7-bit slave address and R/
___
W data agree, which are received after a RESTART condition
is detected, with the value of the I2C address register (S0D).
For the data transmission format when the 10-bit addressing
format is selected, refer to Figure 42, (3) and (4).
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
b7
STSP
SEL
b0
SIS SIP SSC4SSC3 SSC2 SSC1 SSC0
I2C START/STOP condition
control register
(S2D : address 001716)
START/STOP condition set bits
SCL/SDA interrupt pin polarity
selection bit
0 : Falling edge active
1 : Rising edge active
SCL/SDA interrupt pin selection bit
0 : SDA valid
1 : SCL valid
START/STOP condition generating
selection bit
0 : Setup/Hold time short mode
1 : Setup/Hold time long mode
Fig. 41 Structure of I2C START/STOP condition control register
Table 15 Recommended set value to START/STOP condition set bits (SSC4–SSC0) for each oscillation frequency
Oscillation
frequency
f(XIN) (MHz)
Main clock
divide ratio
System
clock φ
(MHz)
START/STOP
condition
control register
SCL release time
(µs)
Setup time
(µs)
Hold time
(µs)
8
2
4
8
8
1
4
2
2
2
2
1
XXX11010
XXX11000
XXX00100
XXX01100
XXX01010
XXX00100
6.75 µs (27 cycles)
6.25 µs (25 cycles)
5.0 µs (5 cycles)
6.5 µs (13 cycles)
5.5 µs (11 cycles)
5.0 µs (5 cycles)
3.5 µs (14 cycles)
3.25 µs (13 cycles)
3.0 µs (3 cycles)
3.5 µs (7 cycles)
3.0 µs (6 cycles)
3.0 µs (3 cycles)
3.25 µs (13 cycles)
3.0 µs (12 cycles)
2.0 µs (2 cycles)
3.0 µs (6 cycles)
2.5 µs (5 cycles)
2.0 µs (2 cycles)
Note: Do not set “000002” or an odd number to the START/STOP condition set bits (SSC4 to SSC0).
S
Slave address R/W
A
Data
A
Data
A/A
P
A
P
7 bits
“0”
1 to 8 bits
1 to 8 bits
(1) A master-transmitter transnmits data to a slave-receiver
S
Slave address R/W
A
Data
A
Data
7 bits
“1”
1 to 8 bits
1 to 8 bits
(2) A master-receiver receives data from a slave-transmitter
S
Slave address
R/W
1st 7 bits
A
Slave address
2nd bytes
A
Data
A
Data
A/A
P
7 bits
“0”
8 bits
1 to 8 bits
1 to 8 bits
(3) A master-transmitter transmits data to a slave-receiver with a 10-bit address
S
Slave address
R/W
1st 7 bits
A
Slave address
2nd bytes
A
Sr
Slave address
R/W
1st 7 bits
“1”
7 bits
“0”
8 bits
7 bits
(4) A master-receiver receives data from a slave-transmitter with a 10-bit address
S : START condition
A : ACK bit
Sr : Restart condition
A
Data
1 to 8 bits
A
Data
A
P
1 to 8 bits
P : STOP condition
R/W : Read/Write bit
Fig. 42 Address data communication format
43
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Example of Master Transmission
An example of master transmission in the standard clock mode, at
the S CL frequency of 100 kHz and in the ACK return mode is
shown below.
(1) Set a slave address in the high-order 7 bits of the I2C address
register (S0D) and “0” into the RWB bit.
(2) Set the ACK return mode and SCL = 100 kHz by setting “8516”
in the I2C clock control register (S2).
(3) Set “0016” in the I2C status register (S1) so that transmission/
reception mode can become initializing condition.
(4) Set a communication enable status by setting “0816” in the I2C
control register (S1D).
(5) Confirm the bus free condition by the BB flag of the I2C status
register (S1).
(6) Set the address data of the destination of transmission in the
high-order 7 bits of the I2C data shift register (S0) and set “0”
in the least significant bit.
(7) Set “F016” in the I2C status register (S1) to generate a START
condition. At this time, an SCL for 1 byte and an ACK clock automatically occur.
(8) Set transmit data in the I2C data shift register (S0). At this time,
an SCL and an ACK clock automatically occur.
(9) When transmitting control data of more than 1 byte, repeat step
(8).
(10) Set “D016” in the I2C status register (S1) to generate a STOP
condition if ACK is not returned from slave reception side or
transmission ends.
Example of Slave Reception
An example of slave reception in the high-speed clock mode, at
the SCL frequency of 400 kHz, in the ACK non-return mode and
using the addressing format is shown below.
(1) Set a slave address in the high-order 7 bits of the I2C address
register (S0D) and “0” in the RWB bit.
(2) Set the no ACK clock mode and S CL = 400 kHz by setting
“2516” in the I2C clock control register (S2).
(3) Set “0016” in the I2C status register (S1) so that transmission/
reception mode can become initializing condition.
(4) Set a communication enable status by setting “0816” in the I2C
control register (S1D).
(5) When a START condition is received, an address comparison
is performed.
(6)•When all transmitted addresses are “0” (general call):
AD0 of the I2C status register (S1) is set to “1” and an interrupt
request signal occurs.
• When the transmitted address matches with the address set
in (1):
ASS of the I2C status register (S1) is set to “1” and an interrupt
request signal occurs.
• In the cases other than the above AD0 and AAS of the I2C
status register (S1) are set to “0” and no interrupt request signal occurs.
(7) Set dummy data in the I2C data shift register (S0).
(8) When receiving control data of more than 1 byte, repeat step (7).
(9) When a STOP condition is detected, the communication ends.
44
■Precautions when using multi-master I2CBUS interface
(1) Read-modify-write instruction
The precautions when the read-modify-write instruction such as
SEB, CLB etc. is executed for each register of the multi-master
I2C-BUS interface are described below.
• I2C data shift register (S0: address 001216)
When executing the read-modify-write instruction for this register during transfer, data may become a value not intended.
• I2C address register (S0D: address 001316)
When the read-modify-write instruction is executed for this register at detecting the STOP condition, data may become a value
not intended. It is because H/W changes the read/write bit
(RWB) at the above timing.
• I2C status register (S1: address 001416)
Do not execute the read-modify-write instruction for this register
because all bits of this register are changed by H/W.
• I2C control register (S1D: address 001516)
When the read-modify-write instruction is executed for this register at detecting the START condition or at completing the byte
transfer, data may become a value not intended. Because H/W
changes the bit counter (BC0-BC2) at the above timing.
• I2C clock control register (S2: address 001616)
The read-modify-write instruction can be executed for this register.
• I 2 C START/STOP condition control register (S2D: address
001716)
The read-modify-write instruction can be executed for this register.
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
(2) START condition generating procedure using multi-master
1. Procedure example (The necessary conditions of the generating procedure are described as the following 2 to 5.
.....
.....
LDA —
(Taking out of slave address value)
SEI
(Interrupt disabled)
BBS 5, S1, BUSBUSY (BB flag confirming and branch pro
cess)
BUSFREE:
STA S0
(Writing of slave address value)
LDM #$F0, S1
(Trigger of START condition generating)
CLI
(Interrupt enabled)
.....
BUSBUSY:
CLI
(Interrupt enabled)
2. Use “Branch on Bit Set” of “BBS 5, $0014, –” for the BB flag
confirming and branch process.
3. Use “STA $12, STX $12” or “STY $12” of the zero page addressing instruction for writing the slave address value to the
I2C data shift register.
4. Execute the branch instruction of above 2 and the store instruction of above 3 continuously shown the above procedure
example.
5. Disable interrupts during the following three process steps:
• BB flag confirming
• Writing of slave address value
• Trigger of START condition generating
When the condition of the BB flag is bus busy, enable interrupts
immediately.
(4) Writing to I2C status register
Do not execute an instruction to set the PIN bit to “1” from “0” and
an instruction to set the MST and TRX bits to “0” from “1” simultaneously. It is because it may enter the state that the SCL pin is
released and the S DA pin is released after about one machine
cycle. Do not execute an instruction to set the MST and TRX bits
to “0” from “1” simultaneously when the PIN bit is “1”. It is because
it may become the same as above.
(5) Process of after STOP condition generating
Do not write data in the I2C data shift register S0 and the I2C status register S1 until the bus busy flag BB becomes “0” after
generating the STOP condition in the master mode. It is because
the STOP condition waveform might not be normally generated.
Reading to the above registers do not have the problem.
(6) ES0 bit switch
In standard clock mode when SSC = “000102” or in high-speed
clock mode, flag BB may switch to “1” if ES0 bit is set to “1” when
SDA is “L”.
Countermeasure:
Set ES0 to “1” when SDA is “H”.
(3) RESTART condition generating procedure
1. Procedure example (The necessary conditions of the generating procedure are described as the following 2 to 4.)
Execute the following procedure when the PIN bit is “0”.
.....
LDM #$00, S1
LDA —
SEI
STA S0
LDM #$F0, S1
CLI
(Select slave receive mode)
(Taking out of slave address value)
(Interrupt disabled)
(Writing of slave address value)
(Trigger of RESTART condition generating)
(Interrupt enabled)
.....
2. Select the slave receive mode when the PIN bit is “0”. Do not
write “1” to the PIN bit. Neither “0” nor “1” is specified for the
writing to the BB bit.
The TRX bit becomes “0” and the SDA pin is released.
3. The SCL pin is released by writing the slave address value to
the I2C data shift register.
4. Disable interrupts during the following two process steps:
• Writing of slave address value
• Trigger of RESTART condition generating
45
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
LPC INTERFACE
LPC interface function is base on Low Pin Count (LPC) Interface
Specification, Revision 1.0. The 3885 supports only I/O read cycle
and
I/O write cycle. There are two channels of bus buffers to the host.
The functions of Input Data Bus Buffer, Output Data Bus Buffer
and Data Bus Buffer Status Register are the same as that of the
8042, 3880 group, 3881 group and 3886 group. It can be written in
or read out from the host controller through LPC interface. LPC interface function block diagram is shown in Figure 43.
Functional input or output pins of LPC interface are shared with
Port 8 (P80 –P8 6). Setting the LPC interface enable bit (bit3 of
LPCCON) to “1” enables LPC interface. Enabling channel i (i = 0,
1) of the data bus buffer is controlled by the data bus buffer i (i =
0, 1) enable bits (bit 4 or bit 5 of LPCCON).
The slave addresses of the data bus buffer channel i (i = 0, 1) are
definable by setting LPCi (i = 0, 1) address register H/L
(LPC0ADL, LPC0ADH, LPC1ADL, LPC1ADH). The bit 2 value of
LPCi address register L is not decoded. This bit returns “0” when
the internal CPU read. The bit 2 of slave address is latched to
XA2i flag when the host controller writes the data.
The input buffer full (IBF) interrupt occurs when the host controller
writes the data. The output buffer empty (OBE) interrupt is generated when the host controller reads out the data. The 3885
merges two input buffer full (IBF) interrupt requests and two output
buffer empty (OBE) interrupt requests as shown in Figure 44.
Table 16 Function explanation of the control pin in LPC interface
Pin name
Input/
Output
P80/LAD0
I/O
P81/LAD1
I/O
P82/LAD2
I/O
P83/LAD3
I/O
Function
These pins communicate address, control and data
information between the host and the data bus buffer of
the 3885.
P84/LFRAME
I
Input the signal to indicate the start of new cycle and
termination of abnormal communication cycles.
P85/LRESET
I
Input the signal to reset the LPC interface function.
P86/LCLK
I
Input the LPC synchronous clock signal.
46
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Address register LL
Address register LH
Address register HL
RD/WR register
Address register HH
P80/LAD0
Start register
Input Data Comparator
P84/LFRAME
P85/LRESET
P86/LCLK
P81/LAD1
Input Data
Bus Buffer [7:4]
Input Data
Bus Buffer [3:0]
Output Data
Bus Buffer [7:4]
Output Data
Bus Buffer [3:0]
Internal CPU Bus
P82/LAD2
LPC Data Bus
Input Control Circuit
P83/LAD3
Data bus buffer status register
U7i
U6i
U5i
U4i
XA2i
U2i
IBFi OBFi
TAR register
SYNC register
Output Control Circuit
Interrupt signal
IBF, OBE
Interrupt Generate
Circuit
0
b6
b5
b4
b3
b2
b1
b0
LPC control register (LPCCON)
Fig. 43 Block diagram of LPC interface function (1ch)
47
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Input buffer
full flag 0 IBF0
Rising edge
detection circuit
One-shot pulse
generating circuit
Input buffer full interrupt
request signal IBF
Input buffer
full flag 1 IBF1
Output buffer
full flag 0
OBF0
Rising edge
detection circuit
OBE0
Output buffer
full flag 1
OBF1
OBE1
One-shot pulse
generating circuit
Rising edge
detection circuit
One-shot pulse
generating circuit
Rising edge
detection circuit
One-shot pulse
generating circuit
Output buffer empty interrupt
request signal OBE
IBF0
IBF1
IBF
Interrupt request is set at this rising edge
OBF0
(OBE0)
OBF1
(OBE1)
OBE
Interrupt request is set at this rising edge
Fig. 44 Interrupt request circuit of data bus buffer
48
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[LPC Control Register (LPCCON)] 002A16
• SYNC output select bit (SYNCSEL)
“00”: OK
“01”: LONG & OK
“10”: Err
“11”: LONG & Err
• LPC interface software reset bit (LPCSR)
“0”: Reset release (automatic)
“1”: Reset
• LPC interface enable bit (LPCBEN)
“0”: P80–P86 works as port
“1”: P80–P86 works as LPC interface
• Data bus buffer 0 enable bit (DBBEN0)
“0”: Data bus buffer 0 disable
“1”: Data bus buffer 0 enable
• Data bus buffer 1 enable bit (DBBEN1)
“0”: Data bus buffer 1 disable
“1”: Data bus buffer 1 enable
[Output Data Bus Buffer i (i = 0, 1)
(DBBOUT0, DBBOUT1)] 002816, 002B16
Writing data to data bus buffer registers (DBB0 , DBB1) address
from the internal CPU means writing to DBBOUTi (i = 0, 1). The
data of DBBOUTi (i = 1, 0) is read out from the host controller
when bit 2 of slave address (A2) is “0”.
[LPCi address register H/L
(LPC0ADL, LPC1ADL / LPC0ADH, LPC1ADH)]
0FF016 to 0FF316
The slave addresses of data bus buffer channel i(i=0,1) are definable by setting LPCi address registers H/L (LPC0ADL, LPC0ADH,
LPC1ADL, LPC1ADH ). These registers can be set and cleared
any time. When the internal CPU reads LPCi address register L,
the bit 2 (A2) is fixed to “0”. The bit 2 of slave address (A2) is
latched to XA2i flag when the host controller writes the data. The
slave addresses, set in these registers, is used for comparing with
the addresses from the host controller.
Bits 0 and 1 of the LPC control register (LPCCON) specify the
SYNC code output.
Bit 2 of the LPC control register (LPCCON) enables the LPC interface to enter the reset state by software. When LPCSR is set to
“1”, LPC interface is initialized in the same manner as the external
“L” input to LRESET pin (See Figure 50). Writing “0” to LPCSR the
reset state will be released after 1.5 cycle of φ and this bit is
cleared to “0”.
[Data Bus Buffer Status Register i (i = 0, 1)
(DBBSTS0, DBBSTS1)] 002916, 002C16
Bits 0, 1 and 3 are read-only bits and indicate the status of the
data bus buffer. Bits 2, 4, 5, 6 and 7 are user definable flags which
can be read and written by software. The data bus buffer status
register can be read out by the host controller when bit 2 of the
slave address (A2) is “1”.
•Bit 0: Output buffer full flag i (OBFi)
This bit is set to “1” when a data is written into the output data bus
buffer i and cleared to “0” when the host controller reads out the
data from the output data bus buffer i.
•Bit 1: Input buffer full flag i (IBFi)
This bit is set to “1” when a data is written into the input data bus
buffer i by the host controller, and cleared to “0” when the data is
read out from the input data bus buffer i by the internal CPU.
•Bit 3: XA2 flag (XA2i)
The bit 2 of slave address is latched while a data is written into the
input data bus buffer i.
[Input Data Bus Buffer i(i=0,1)
(DBBIN0, DBBIN1)] 002816, 002B16
In I/O write cycle from the host controller, the data byte of the data
phase is latched to DBBINi (i=0,1). The data of DBBINi can be
read out form the data bus buffer registers (DBB0, DBB1) address
in SFR area.
49
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
LPC control register
b7
b6
b5
b4
b3
b2
b1
b0
Symbol
LPCCON
Address
002A16
Bit symbol
When reset
000000002
Bit name
Function
SYNC output select bit
00 : OK
01 : Long & OK
10 : Err
11 : Long & Err
LPCSR
LPC interface software reset bit
0 : Reset release(automatic)
1 : Reset
LPCEN
LPC interface enable bit
0 : P80 to P86 as port
1 : LPC interface enable
DBBEN0
Data bus buffer 0 enable bit
0 : Data bus buffer 0 disable
1 : Data bus buffer 0 enable
DBBEN1
Data bus buffer 1 enable bit
0 : Data bus buffer 1 disable
1 : Data bus buffer 1 enable
SYNCSEL
R W
Cannot write to this bit.
Returns “0” when read.
Fig. 45 LPC control register
Data bus buffer status register i (i = 0, 1)
b7
b6
b5
b4
b3
b2
b1
b0
Symbol
DBBSTS0
DBBSTS1
Bit symbol
Bit name
When reset
000000002
000000002
Function
OBFi
Output buffer full flag
0 : Buffer empty
1 : Buffer full
IBFi
Input buffer full flag
0 : Buffer empty
1 : Buffer full
U2i
User definable flag
This flag can be freely defined
by user.
XA2i
XA2i flag
This flag indicates the A2
status when IBFi flag is set.
U4i
User definable flag
This flag can be freely defined
by user.
U5i
U6i
U7i
Fig. 46 Data bus buffer control register
50
Address
002916
002C16
R W
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
LPCi address register L (i=0,1)
b7
b6
b5
b4
b3
b2
b1
b0
(Note2)
Symbol
LPC0ADL
LPC1ADL
Bit symbol
Address
0FF02
0FF22
When reset
000000002
000000002
R W
Bit name
LPCSAD0
Slave address bit 0
LPCSAD1
Slave address bit 1
LPCSAD2
Slave address bit 2 (Note 1)
LPCSAD3
Slave address bit 3
LPCSAD4
Slave address bit 4
LPCSAD5
Slave address bit 5
LPCSAD6
Slave address bit 6
LPCSAD7
Slave address bit 7
Notes 1: Always returnes “0” when read , even if writing “1” to this bit.
2: Do not set the same 16-bit slave address to both channel 0 and channel 1.
LPCi address register H (i=0,1)
b7
b6
b5
b4
b3
b2
b1
b0
Symbol
LPC0ADH
LPC1ADH
Bit symbol
Address
0FF12
0FF32
Bit name
LPCSAD8
Slave address bit 8
LPCSAD9
Slave address bit 9
LPCSAD10
Slave address bit 10
LPCSAD11
Slave address bit 11
LPCSAD12
Slave address bit 12
LPCSAD13
Slave address bit 13
LPCSAD14
Slave address bit 14
LPCSAD15
Slave address bit 15
When reset
000000002
000000002
R W
Fig. 47 LPC related registers
51
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Basic Operation of LPC Interface
(2) Example for I/O read cycle
Set up steps for LPC interface is as below.
•Set the LPC interface enable bit (bit3 of LPCCON) to “1”.
•Choose which data bus buffer channel use.
•Set the data bus buffer i enable bit (i = 0, 1) (bit 4 or 5 of
LPCCON) to “1”.
•Set the slave address to LPCi address register L and H (i = 0, 1)
(LPC0ADL, LPC0ADH, LPC1ADL, LPC1ADH).
The I/O read cycle timing is shown in Figure 49. The standard
transfer cycle number of I/O read cycle is 13. The data on LAD
[3:0] is monitored at every rising edge of LCLK. The communication starts from the falling edge of LFRAME.
•1st clock: The last clock when LFRAME is “Low”. The host sends
“00002” on LAD [3:0] for communication start.
•2nd clock: LFRAME is “High”. The host sends “000X 2” on LAD
[3:0] to inform the cycle type as I/O read.
• From 3rd clock to 6th clock: In these four cycles , the host sends
16-bit slave address. The 3885 compares it with the LPCi address register H or L (i = 0, 1).
3rd clock: The slave address bit [15:12].
4th clock: The slave address bit [11:8].
5th clock: The slave address bit [7:4].
6th clock: The slave address bit [3:0].
• 7thclock and 8thclock are used for turning the communication direction from the host→the peripheral to the peripheral→the host.
7th clock: The host outputs “11112” on LAD [3:0].
8th clock: The LAD [3:0] is set to tri-state by the host to
turn the communication direction.
• 9th clock: The 3885 outputs “00002” (SYNC OK) to LAD [3:0] for
acknowledgment.
• 10th clock and 11th clock are used for one data byte transfer from
the output data bus buffer i (DBBOUTi) or data bus buffer status
register i (DBBSTSi).
10th clock: The 3885 sends the data bit [3:0].
11th clock: The 3885 sends the data bit [7:4].
th
• 12 clock: The 3885 outputs “11112” to LAD [3:0]. In this timing
OBFi (bit 2 of DBBSTSi) is cleared to “0” and OBE
interrupt signal is generated.
• 13th clock: The LAD [3:0] is set to tri-state by the host to turn the
communication direction.
(1) Example of I/O write cycle
The I/O write cycle timing is shown in Figure 48. The standard
transfer cycle number of I/O write cycle is 13. The communication
starts from the falling edge of LFRAME.
The data on LAD [3:0] is monitored at every rising edge of LCLK.
• 1st clock: The last clock when LFRAME is “Low”. The host send
“00002” on LAD [3:0] for communication start.
• 2 nd clock: LFRAME is “High”. The host send “001X 2” on LAD
[3:0] to inform the cycle type as I/O write.
• From 3rd clock to 6th clock : In these four cycles , the host sends
16-bit slave address. The 3885 compares it with the LPCi address register H and L (i = 0, 1).
3rd clock: The slave address bit [15:12].
4th clock: The slave address bit [11:8].
5th clock: The slave address bit [7:4].
6th clock: The slave address bit [3:0].
• 7th clock and 8th clock are used for one data byte transfer. The
data is written to the input data bus buffer (DBBINi, i = 0, 1)
7th clock: The host sends the data bit [3:0].
8th clock: The host sends the data bit [7:4].
th
• 9 clock and 10th clock are for turning the communication direction from the host→the peripheral to the slave→the host.
9th clock: The host outputs “11112” on LAD [3:0].
10th clock: The LAD [3:0] is set to tri-state by the host to
turn the communication direction.
• 11th clock: The 3885 outputs “00002” (SYNC OK) to LAD [3:0] for
acknowledgment.
• 12th clock: The 3885 outputs “11112” to LAD [3:0]. In this timing
the address bit 2 is latched to XA2i (bit3 of DBBSTSi),
IBFi (bit 1 of DBBSTSi) is set to “1” and IBF interrupt
signal is generated.
• 13th clock: The LAD [3:0] is set to tri-state by the host to turn the
communication direction.
52
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
● Data
write (I/O write cycle)
START
CYCTYPE
+
DIR
ADDRESS
DATA
TAR
SYNC
TAR
LCLK
LFRAME
(Note)
LAD [3:0]
Input data bus buffer i
XA2i flag
IBFi flag
driven by the host
● Command
driven by the 3885
write (I/O write cycle)
START
CYCTYPE
+
DIR
ADDRESS
DATA
TAR
SYNC
TAR
LCLK
LFRAME
(Note)
LAD [3:0]
Input data bus buffer i
XA2i flag
IBFi flag
driven by the host
driven by the 3885
Note: LAD0 to LAD3 pins remain tri-state after transfer completion.
Fig. 48 Data and command write timing
53
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
● Data
Read (I/O read cycle)
START
CYCTYPE
+
DIR
ADDRESS
TAR
SYNC
DATA
TAR
LCLK
LFRAME
(Note 1)
LAD [3:0]
Output data bus buffer i
OBFi flag
driven by the host
●
driven by the 3885
Status Read (I/O read cycle)
START
CYCTYPE
+
DIR
ADDRESS
TAR
SYNC
DATA
TAR
LCLK
LFRAME
(Note 1)
LAD [3:0]
OBFi flag
(Note 2)
driven by the host
driven by the the 3885
Notes 1: LAD0 to LAD3 pins remain tri-state after transfer completion.
2: OBFi flag does not change.
Fig. 49 Data and status read timing
54
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
LPCSR write signal
LPCSR bit
(LPC interface software reset signal)
1.5 cycle of φ
LRESET
CPU Data bus bit 2
LPCSR write signal
D
Q
D
CK
R
Q
CK
R
D
LPC interface reset signal
Q
CK
R
φ
CPU RESET
CPU RESET
Fig. 50 Reset timing and block
Table 17 Reset conditions of LPC interface function
Pin name / Internal register
Pin
P80/LAD0
LRESET = “L”
Note
Tri-state
P81/LAD1
P82/LAD2
P83/LAD3
P84/LFRAME
Input
P85/LRESET
P86/LCLK
LPC bus interface function
Input
Input data bus buffer registeri
Output data bus buffer registeri
Keep same value before
LRESET goes “L”.
Internal register
Uxi flag 7, 6, 5, 4, 2
XA2i flag
IBFi flag
Initialization to “0”.
Initialization to “0”.
There is possibility to generate
OBFi flag
Initialization to “0”.
IBF interrupt request.
There is possibility to generate
LPCi address register
Keep same value before
OBE interrupt request.
LRESET goes “L”.
LPCCON
55
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
SERIALIZED INTERRUPT
The serialized IRQ circuit communicates the interrupt status to the
host controller based on the Serialized IRQ Support for PCI System,
Version 6.0.
Table 18 shows the summary of serialized interrupt of 3885.
Table 18 Smmary of serialized IRQ function
Item
The factors of serialized IRQ
The number of frame
Operation clock
Clock restart
Clock stop inhibition
56
Function
The numbers of serialized IRQ factor that can output simultaneously are 3.
• Channel 0 (IRQ1,IRQ2)
➀ Setting Software IRQi (i = 1, 12) request bit (bits 0, 1 of SERIRQ) to “1”.
➁ The “1” of OBF0 and Hardware IRQi ( i=1, 12) request bit (bits 3, 4 of SERCON) to “1”.
• Channel 1 (IRQx ; user selectable)
➀ Setting the IRQx request bit (bit 7 of SERIRQ) to “1”.
➁ The “1” of OBF1 and Hardware IRQx request bit to “1”.
• Channel 0 (IRQ1, IRQ12)
➀ Setting Software IRQ1 request bit (bit 0 of SERIRQ) to “1” or detecting “1” of OBF0 with
“1” of Hardware IRQ1 request bit (bit 4 of SERCON) selects IRQ1 Frame .
➁ Setting IRQ12 Software request bit (bit 1 of SERIRQ) to “1” or detecting “1” of OBF0 with
“1” of Hardware IRQ1 request bit (bit 4 of SERCON) selects IRQ12 Frame.
• Channel 1 (IRQx ; user selectable)
Setting IRQx frame select bit (bit 2-6 of SERIRQ) selects IRQ 1–15 frame or extend
frame 0–10.
Synchronized with LCLK (Max. 33 MHz).
LPC clock restart enable bit (bit 1 of SERCON) enables restart owing to “L” output of CLKRUN
with the interrupt when the LPC clock has stopped or slowed down.
LPC clock stop inhibition bit (bit 2 of SERCON) enables the inhibition of clock stop control
during the IRQSER cycle when the clock tends to stop or slow down.
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Internal data bus
Serialized IRQ control register
Serialized IRQ request register
b7 b6 b5 b4 b3 b2 b1 b0
b7 b6 b5 b4 b3 b2 b1 b0
Clock stop inhibition enable
and clock restart enable
Software Serialized IRQ request
OBF interrupt control
Serialized IRQ enable
Serialized interrupt request
control circuit
OBF0 – OBF1
Serialized
IRQ request
IRQx frame number
Frame number
SERIRQ
Serialized interrupt
control circuit
Clock operation
status and finish
acknowledgement
Clock restart request
and start frame
activate request
Clock monitor
control circuit
*
CLKRUN#
LCLK
LRESET#
CPU clock φ
* Open Drain
Fig. 51 Block diagram of serialized interrupt
57
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Register Explanation
Bit 3 : Hardware IRQ1 request bit (SEIR1)
When this bit is “1”, OBF0 status is directly connected to the IRQ1
frame.
The serialized IRQ function is configured and controlled by the serialized IRQ request register (SERIRQ) and the serialized IRQ
control register (SERCON).
Bit 4 : Hardware IRQ12 request bit (SEIR12 )
When this bit is “1”, OBF0 status is directly connected to IRQ12
frame.
[Serialized IRQ control register (SERCON)] 001D16
Bit 0 : Serialized IRQ enable bit (SIRQEN )
This bit enables/disables the serialized IRQ interface. When this
bit is “1”, use of serialized IRQ is enabled. Then P87 functions as
IRQ/Data line (SERIRQ) and P47 functions as CLKRUN.
Output structure of CLKRUN pin becomes N-channel open drain.
Bit 5 : Hardware IRQx request bit (SEIRx )
When this bit is “1”, OBF1 status is directly connected to the IRQx
frame.
Bit 1 : LPC clock restart enable bit (RUNEN )
Setting this bit to “1” enables clock restart with “L” output of
CLKRUN.
Bit 6 : IRQ1/IRQ12 disable bit (SCH0EN )
This bit controls whether the serialized IRQ channel 0 transfers
the IRQ1 and IRQ12 frame to the host or not.
Bit 2 : LPC clock stop inhibition bit (SUPEN )
Setting this bit to “1” makes CLKRUN output change to “L” for inhibiting the clock stop.
Bit 7 : IRQx output polarity bit (SCH1POL)
This bit selects IRx frame output level.
Serialized IRQ control register
b7
b6
b5
b4
b3
b2
b1
b0
Symbol
SERCON
Bit symbol
Bit name
When reset
000000002
Function
SIRQEN
Serialized IRQ enable bit
0 : Serialized IRQ disable
1 : Serialized IRQ enable
RUNEN
LPC clock restart enable bit
0 : Clock restart disable
1 : Clock restart enable
SUPEN
LPC clock stop inhibition bit
0 : Stop inhibition control disable
1 : Stop inhibition control enable
SEIR1
Hardware IRQ1 request bit
0 : No IRQ1 request
1 : OBF0 synchronized IRQ1 request
SEIR12
Hardware IRQ12 request bit 0 : No IRQ12 request
1 : OBF0 synchronized IRQ12 request
SEIRx
Hardware IRQx request bit
0 : No IRQx request
1 : OBF1 synchronized IRQx request
SCH0EN
IRQ1/IRQ12 disable bit
0 : IRQ1/IRQ12 output enable
1 : IRQ1/IRQ12 output disable
SCH1POL
IRQx output polarity bit
0 : -Request Hiz-Hiz-Hiz
-No request L-H-Hiz
1 : -Request L-H-Hiz
-No request Hiz-Hiz-Hiz
Fig. 52 Configuration of serialized IRQ control register
58
Address
001D16
R
W
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
[Serialized IRQ request register (SERIRQ)] 001F16
The interrupt source is definable by this register.
Bit 0 : Software IRQ1 request bit (IR1)
SERIRQ line shows IR1 value at the sample phase of IRQ1 frame,
when the SCH0EN is “1”.
Bit 1 : Software IRQ12 request bit (IR12)
SERIRQ line shows IR12 value at the sample phase of IRQ12
frame, when the SCH0EN is “1”.
Bits 2-6 : IRQx frame select bits (ISi, i = 0–4)
These bits select the active IRQ frame of serial IRQ channel 1.
When these bit are “000002”, the serial IRQ channel 1 is disabled.
Bit 7 : Software IRQx request bit (IRx)
SERIRQ line shows IRx value at the sample phase of IRQx frame
which is selected by bits 2 to 6 of SERIRQ. Output level is selectable by the IRQx output polarity bit (SCH1POL).
Serialized IRQ request register
b7
b6
b5
b4
b3
b2
b1
b0
Symbol
SERIRQ
Address
001F16
Bit symbol
When reset
000000002
Bit name
Function
IR1
Software IRQ1
request bit
0: No IRQ1 request
1: IRQ1 request
IR12
Software IRQ12
request bit
0: No IRQ12 request
1: IRQ12 request
IS0
IRQx frame select bit
b6b5b4b3b2
0 0 0 0 0 : Disable serial IRQ channel 1
0 0 0 0 1 : IRQ1 Frame
0 0 0 1 0 : IRQ2 Frame
0 0 0 1 1 : IRQ3 Frame
0 0 1 0 0 : IRQ4 Frame
0 0 1 0 1 : IRQ5 Frame
0 0 1 1 0 : IRQ6 Frame
0 0 1 1 1 : IRQ7 Frame
0 1 0 0 0 : IRQ8 Frame
0 1 0 0 1 : IRQ9 Frame
0 1 0 1 0 : IRQ10 Frame
0 1 0 1 1 : IRQ11 Frame
0 1 1 0 0 : IRQ12 Frame
0 1 1 0 1 : IRQ13 Frame
0 1 1 1 0 : IRQ14 Frame
0 1 1 1 1 : IRQ15 Frame
1 0 0 0 0 : Do not select
1 0 0 0 1 : Do not select
1 0 0 1 0 : Do not select
1 0 0 1 1 : Do not select
1 0 1 0 0 : Do not select
1 0 1 0 1 : Extend Frame 0
1 0 1 1 0 : Extend Frame 1
1 0 1 1 1 : Extend Frame 2
1 1 0 0 0 : Extend Frame 3
1 1 0 0 1 : Extend Frame 4
1 1 0 1 0 : Extend Frame 5
1 1 0 1 1 : Extend Frame 6
1 1 1 0 0 : Extend Frame 7
1 1 1 0 1 : Extend Frame 8
1 1 1 1 0 : Extend Frame 9
1 1 1 1 1 : Extend Frame 10
IS1
IS2
IS3
IS4
IRx
R W
Software IRQx
request bit
0: No IRQx request
1: IRQx request
Fig. 53 Structure of serialized IRQ request register
59
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Operation of Serialized IRQ
A cycle operation of serialized IRQ starts with Start Frame and finishes with Stop Frame. There are two modes of operation :
Continuous (Idle) mode and Quiet (Active) mode. The next operation mode is determined by monitoring the stop frame pulse width.
●Timing of serialized IRQ cycle
Figure 54 shows the timing diagram of serialized IRQ cycle.
(1) Start Frame
The Start Frame is detected when the SERIRQ line remains “L” in
4 to 8 clocks.
Start frame
IRQ0 frame
IRQ1 frame
(2) IRQ/Data Frame
Each IRQ/Data Frame is three clocks. When the IRQi (i = 0, 1, x)
request is “0”, then the SERIRQ line is driven to “L” during the
Sample phase (1st clock) of the corresponding IRQ/Data frame,
to “H” during the Recovery phase (2nd clock), to tri-state during
the Turn-around phase (3rd clock). When the IRQi request is “1”,
then the SERIRQ line is tri-state in all phases (3 clocks period).
(3) Stop Frame
The Stop Frame is detected when the SERIRQ line remains “L” in
2 or 3 clocks. The next operation mode is Quiet mode when the
pulse width of “L” is 2 clocks. The next operation mode is the
Continuous mode when the pulse width is 3 clocks.
IRQ15 frame
IOCHK frame
Stop frame
Clock
SERIRQ
Driver source
Host control
Fig. 54 Timing diagram of serialized IRQ cycle
60
IRQ1
device
control
IRQ15
device
control
Host control
To the next cycle
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Operation Mode
Figure 55 shows the timing of continuous mode; Figure 56 shows
that of Quiet mode.
(1) Continuous mode
Serialized IRQ cycles starts in Continuous mode after CPU reset
in the case of LRESET = “L” and the previous stop frame being 3
clocks.
Start frame (Note)
After receiving the start frame; the IRQ1 Frame, IRQ12 Frame or
IRQx frame is asserted.
Note : If the pulse width of “L” is less than 4 clocks, or 9 clocks or
more; the start frame is not detected and the next start (the
falling edge of SERIRQ) is waited.
IRQ0 frame
IRQ1 frame
IRQ2 frame
IRQ3 frame
LCLK
SERIRQ line
Host SERIRQ output
3885 SERIRQ output
Drive source
Host
3885
Note: The start frame count is 4 clocks as exemple.
Fig. 55 Timing diagram of Continuous mode
(2) Quiet mode
At clock stop, clock slow down or the pulse width of the last stop
frame being 2 clocks, it is the Quiet mode.
In this mode the 3885 drives the SERIRQ line to “L” in the 1 st
clock. After that the host drives the rest start frame (Note). The
IRQ1 frame, IRQ12 frame or IRQx frame is asserted.
Start frame (Note)
Note: When the sum of pulse width of “L” driven by the 3885 in
the 1 st clock and driven by the host in the rest clocks is
within 4 to 8-clock cycles, the start frame is detected.
If the sum of pulse width of “L” is less than 4 clocks, or 9
clocks or more; the start frame is not detected and the next
start (the falling edge of SERIRQ) is waited.
IRQ0 frame
IRQ1 frame
IRQ2 frame
IRQ3 fra
LCLK
SERIRQ line
Host SERIRQ output
3885 SERIRQ output
Drive source
3885
3885
Host
Note: The start frame count is 4 clocks as exemple
Fig. 56 Timing diagram of Quiet mode
61
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Clock Restart/Stop Inhibition Request
Asserting the CLKRUN signal can request the host to restart for
clocks stopped or slowed down, or maintain the clock tending to
stop or slow down.
Figure 57 shows the timing diagram of clock restart request; Figure 58 shows an example of timing of clock stop inhibition
request.
(1) Clock restart operation
In case the LPC clock restart enable bit (bit 1 of SERCON) is “1”
and the CLKRUN (BUS) is “H”, when the serialized interrupt request occurs, the 3885 drives CLKRUN to “L” for requesting the
PCI clock generator to restart the LCLK if the clock is slowed
down or stopped.
LCLK
Bus CLKRUN
Central Resource CLKRUN
Restart frame
3885 CLKRUN
Start frame
Bus SERIRQ
Host SERIRQ
3885 SERIRQ
φ
Interrupt request
Internal restart
request signal
Fig. 57 Timing diagram of clock restart request
(2) Clock stop inhibition request
In case the LPC clock stop inhibition bit (bit 2 of SERCON) is “1”
and the serialized interrupt request is held, if the LCLK tends to
stop, the 3885 drives CLKRUN to “L” for requesting the PCI clock
generator not to stop LCLK.
LCLK
Bus CLKRUN
Central Resource CLKRUN
Inhibition
request
3885 CLKRUN
Bus SERIRQ
Interrupt request
Internal inhibition request signal
Fig. 58 Timing diagram of clock stop inhibition request
62
IRQSER cycle
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
A-D CONVERTER
[A-D Conversion Register 1,2 (AD1, AD2)]
003516, 003816
The A-D conversion register is a read-only register that stores the
result of an A-D conversion. When reading this register during an
A-D conversion, the previous conversion result is read.
Bit 7 of the A-D conversion register 2 is the conversion mode selection bit. When this bit is set to “0,” the A-D converter becomes
the 10-bit A-D mode. When this bit is set to “1,” that becomes the
8-bit A-D mode. The conversion result of the 8-bit A-D mode is
stored in the A-D conversion register 1. As for 10-bit A-D mode,
10-bit reading or 8-bit reading can be performed by selecting the
reading procedure of the A-D conversion register 1, 2 after A-D
conversion is completed (in Figure 60).
The A-D conversion register 1 performs the 8-bit reading inclined
to MSB after reset, the A-D conversion is started, or reading of the
A-D converter register 1 is generated; and the register becomes
the 8-bit reading inclined to LSB after the A-D converter register 2
is generated.
Channel Selector
The channel selector selects one of ports P60/AN0 to P6 7/AN7 ,
and inputs the voltage to the comparator.
Comparator and Control Circuit
The comparator and control circuit compares an analog input voltage with the comparison voltage, and then stores the result in the
A-D conversion registers 1, 2. When an A-D conversion is completed, the control circuit sets the A-D conversion completion bit
and the A-D interrupt request bit to “1”.
Note that because the comparator consists of a capacitor coupling, set f(XIN) to 500 kHz or more during an A-D conversion.
b7
b0
AD/DA control register
(ADCON : address 003416)
Analog input pin selection bits
b2 b1 b0
0
0
0
0
1
1
1
1
[AD/DA Control Register (ADCON)] 003416
The AD/DA control register controls the A-D conversion process.
Bits 0 to 2 select a specific analog input pin. Bit 3 signals the
completion of an A-D conversion. The value of this bit remains at
“0” during an A-D conversion, and changes to “1” when an A-D
conversion ends. Writing “0” to this bit starts the A-D conversion.
0: P60/AN0
1: P61/AN1
0: P62/AN2
1: P63/AN3
0: P64/AN4
1: P65/AN5
0: P66/AN6
1: P67/AN7
A-D conversion completion bit
0: Conversion in progress
1: Conversion completed
PWM0 output pin selection bit
0: P56/PWM01
1: P30/PWM00
Comparison Voltage Generator
The comparison voltage generator divides the voltage between
AVSS and VREF into 1024, and outputs the divided voltages in the
10-bit A-D mode (256 division in 8-bit A-D mode).
The A-D converter successively compares the comparison voltage
Vref in each mode, dividing the VREF (see below), with the input
voltage.
• 10-bit A-D mode (10-bit reading)
VREF
Vref = 1024 ✕ n (n = 0–1023)
• 10-bit A-D mode (8-bit reading)
VREF
Vref = 256 ✕ n (n = 0–255)
• 8-bit A-D mode
VREF
Vref = 256 ✕ (n–0.5) (n = 1–255)
=0
(n = 0)
0
0
1
1
0
0
1
1
PWM1 output pin selection bit
0: P57/PWM11
1: P31/PWM10
DA1 output enable bit
0: DA1 output disabled
1: DA1 output enabled
DA2 output enable bit
0: DA2 output disabled
1: DA2 output enabled
Fig. 59 Structure of AD/DA control register
10-bit reading
(Read address 003816 before 003516)
b7
(Address 003816)
0
b0
b9 b8
b7
(Address 003516)
b0
b7 b6 b5 b4 b3 b2 b1 b0
Note: Bits 2 to 6 of address 003816 becomes “0”at reading.
8-bit reading (Read only address 003516)
b7
(Address 003516)
b0
b9 b8 b7 b6 b5 b4 b3 b2
Fig. 60 Structure of 10-bit A-D mode reading
63
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Data bus
AD/DA control register
(Address 003416)
b7
b0
3
A-D interrupt request
A-D control circuit
Channel selector
P60/AN0
P61/AN1
P62/AN2
P63/AN3
P64/AN4
P65/AN5
P66/AN6
P67/AN7
Comparator
A-D conversion register 2
A-D conversion register 1
10
Resistor ladder
VREF AVSS
Fig. 61 Block diagram of A-D converter
64
(Address 003816)
(Address 003516)
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
D-A CONVERTER
The 3885 group has two internal D-A converters (DA1 and DA2)
with 8-bit resolution.
The D-A converter is performed by setting the value in each D-A
conversion register. The result of D-A conversion is output from
the DA1 or DA2 pin by setting the DA output enable bit to “1”.
When using the D-A converter, the corresponding port direction
register bit (P56 for DA1 or P57 for DA2) must be set to “0” (input
status).
The output analog voltage V is determined by the value n (decimal
notation) in the D-A conversion register as follows:
Data bus
D-A1 conversion register (8)
V = VREF ✕ n/256 (n = 0 to 255)
Where VREF is the reference voltage.
R-2R resistor ladder
DA1 output enable bit
P56/DA1/PWM01
D-A2 conversion register (8)
At reset, the D-A conversion registers are cleared to “0016”, the
DA output enable bits are cleared to “0”, and the P56/DA1/PWM01
and P57/DA2/PWM11 pins become high impedance.
The DA output does not have buffers. Accordingly, connect an external buffer when driving a low-impedance load.
R-2R resistor ladder
DA2 output enable bit
P57/DA2/PWM11
Fig. 62 Block diagram of D-A converter
“0” DA1 output enable bit
R
R
R
R
R
R
R
2R
P56/DA1/PWM01
“1”
2R
2R
MSB
D-A1 conversion register
“0”
2R
2R
2R
2R
2R
2R
LSB
“1”
AVSS
VREF
Fig. 63 Equivalent connection circuit of D-A converter (DA1)
65
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
COMPARATOR CIRCUIT
Comparator Configuration
The comparator circuit consists of the ladder resistors, the analog
comparators, a comparator control circuit, the comparator reference input selection bit (bit 7 of PCTL2), a comparator data
register (CMPD), the comparator reference power source input pin
(P20/CMPREF) and analog input pins (P30–P37). The analog input
pin (P30–P37) also functions as an ordinary digital port.
Comparator Operation
To activate the comparator circuit, first set port P3 to input mode
by setting the corresponding direction register (P3D) to “0” to use
port P3 as an analog voltage input pin. The internal fixed analog
voltage (VCC ✕ 29/32) can be generated by setting “1” to the comparator reference input selection bit (bit 7 of PCTL2). The internal
fixed analog voltage becomes about 2.99 V at VCC = 3.3 V. When
setting “0” to the comparator reference input selection bit, the P20/
CMPREF pin becomes the comparator reference power source input pin and it is possible to input the comparator reference power
source optionally from the external. The voltage comparison is immediately performed by the writing operation to the comparator
data register (CMPD). After 14 cycles of the internal system clock
φ (the time required for the comparison), the comparison result is
stored in the comparator data register (CMPD).
If the analog input voltage is greater than the internal reference
voltage, each bit of this register is “1”; if it is less than the internal
reference voltage, each bit of this register is “0”. To perform another comparison, the voltage comparison must be performed
again by writing to the comparator data register (CMPD).
Read the result when 14 cycles of φ or more have passed after the
comparator operation starts. The ladder resistor is turned on during 14 cycles of φ , which is required for the comparison, and the
reference voltage is generated. An unnecessary current is not
consumed because the ladder resistor is turned off while the comparator operation is not performed. Since the comparator consists
of capacitor coupling, the electric charge may lost if the clock frequency is low.
Keep the clock frequency more than 1 MHz during the comparator
operation. Do not execute the STP, WIT, or port P3 I/O instruction.
Data bus
8
8
P3 (8)
Comparator data register
b0
P37
Comparator
P36
Comparator
“0”
P30
Comparator
P20/CMPREF
Fig. 64 Comparator circuit
66
Comparator reference input selection bit
(bit 7 of PCTL2)
VCC
“1”
Comparator
Comparator connecting control circuit Ladder resistor
signal
connecting signal VSS
VCC✕29/32
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
RESET CIRCUIT
____________
To reset the microcomputer, RESET pin should be held at an “L”
level for 16 XIN cycle or more. (When the power source voltage
should be between 3.3V ± 0.3V and the oscillation should be
____________
stable.) Then the RESET pin set to “H”, the reset state is released.
After the reset is completed, the program starts from the address
contained in address FFFD 16 (high-order byte) and address
FFFC16 (low-order byte). Make sure that the reset input voltage is
less than 0.6 V for VCC of 3.0 V.
Poweron
RESET
Power source
voltage
0V
VCC
Reset input
voltage
0V
(Note)
0.2VCC
Note : Reset release voltage ; Vcc=3.0 V
RESET
VCC
Power source
voltage detection
circuit
Fig. 65 Reset circuit example
XIN
φ
RESET
Internal
reset
Address
?
?
?
?
FFFC
FFFD
ADH,L
Reset address from the vector table.
?
Data
?
?
?
ADL
ADH
SYNC
XIN: 10.5 to 18.5 clock cycles
Notes 1: The frequency relation of f(XIN) and f(φ) is f(XIN)=8 • f(φ).
2: The question marks (?) indicate an undefined data that depends on the previous state.
Fig. 66 Reset sequence
67
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Address Register contents
(1)
Port P0 (P0)
000016
0016
(38) Timer X (TX)
002516
FF16
(2)
Port P0 direction register (P0D)
000116
0016
(39) Prescaler Y (PREY)
002616
FF16
(3)
Port P1 (P1)
000216
0016
(40) Timer Y (TY)
002716
FF16
(4)
Port P1 direction register (P1D)
000316
0016
(41) Data bus buffer register 0 (DBB0) 002816 X X X X X X X X
(5)
Port P2 (P2)
000416
0016
(42) Data bus buffer status register 0 (DBBSTS0)
002916
0016
(6)
Port P2 direction register (P2D)
000516
0016
(43) LPC control register (LPCCON)
002A16
0016
(7)
Port P3 (P3)
000616
0016
(44) Data bus buffer register 1 (DBB1) 002B16 X X X X X X X X
(8)
Port P3 direction register (P3D)
000716
0016
(45) Data bus buffer status register 1 (DBBSTS1)
002C16
0016
(9)
Port P4 (P4)
000816
0016
(46) Comparator data register (CMPD)
002D16
0016
(10) Port P4 direction register (P4D)
000916
0016
(47) Port control register 1 (PCTL1)
002E16
0016
(11) Port P5 (P5)
000A16
0016
(48) Port control register 2 (PCTL2)
002F16
0016
(12) Port P5 direction register (P5D)
000B16
0016
(49) PWM0H register (PWM0H)
003016 X X X X X X X X
(13) Port P6 (P6)
000C16
0016
(50) PWM0L register (PWM0L)
003116 X 0 X X X X X X
(14) Port P6 direction register (P6D)
000D16
0016
(51) PWM1H register (PWM1H)
003216 X X X X X X X X
(15) Port P7 (P7)
000E16
0016
(52) PWM1L register (PWM1L)
003316 X 0 X X X X X X
(16) Port P7 direction register (P7D)
000F16
0016
(53) AD/DA control register (ADCON)
003416 0 0 0 0 1 0 0 0
(17) Port P8 (P8)
001016
0016
(54) A-D conversion register 1 (AD1)
003516 X X X X X X X X
(18) Port P8 direction register (P8D)
001116
0016
(55) D-A1 conversion register (DA1)
003616
0016
(19) I2C data shift register (S0)
001216 X X X X X X X X
(56) D-A2 conversion register (DA2)
003716
0016
(57) A-D conversion register 2 (AD2)
003816 0 0 0 0 0 0 X X
(58) Interrupt source selection register (INTSEL)
003916
0016
0016
(20) I2C address register (S0D)
001316
(21) I2C status register (S1)
001416 0 0 0 1 0 0 0 X
(22) I2C control register (S1D)
001516
0016
(59) Interrupt edge selection register (INTEDGE)
003A16
(23) I2C clock control register (S2)
001616
0016
(60) CPU mode register (CPUM)
003B16 0 1 0 0 1 0 0 0
(24) I2C start/stop condition control register (S2D)
001716 0 0 0 1 1 0 1 0
0016
(61) Interrupt request register 1 (IREQ1)
003C16
0016
(25) Transmit/Receive buffer register (TB/RB)
001816
X X X X X X X X
(62) Interrupt request register 2 (IREQ2)
003D16
0016
(26) Serial I/O status register (SIOSTS)
001916 1 0 0 0 0 0 0 0
(63) Interrupt control register 1 (ICON1)
003E16
0016
(27) Serial I/O control register (SIOCON)
001A16
(64) Interrupt control register 2 (ICON2)
003F16
0016
(28) UART control register (UARTCON)
001B16 1 1 1 0 0 0 0 0
(65) LPC0 address register L (LPC0ADL)
0FF016
0016
(29) Baud rate generator (BRG)
001C16 X X X X X X X X
(66) LPC0 address register H (LPC0ADH)
0FF116
0016
0016
(30) Serialized IRQ control register (SERCON)
001D16
(67) LPC1 address register L (LPC1ADL)
0FF216
0016
(31) Watchdog timer control register (WDTCON)
001E16 0 0 1 1 1 1 1 1
(68) LPC1 address register H (LPC1ADH)
0FF316
0016
(32) Serialized IRQ request register (SERIRQ)
001F16 X X X X X X X X
(69) Port P5 input register (P5I)
0FF816
0016
(33) Prescaler 12 (PRE12)
002016
FF16
(70) Port control register 3 (PCTL3)
0FF916
0016
(34) Timer 1 (T1)
0016
002116
0116
(71) Flash memory control register (FMCR) 0FFE16 X X X 0 0 0 0 1
(35) Timer 2 (T2)
002216
FF16
(72) Processor status register
(PS)
(36) Timer XY mode register (TM)
002316
0016
(73) Program counter
(PCH)
FFFD16 contents
(37) Prescaler X (PREX)
002416
FF16
(PCL)
FFFC16 contents
Note : X : Not fixed
Since the initial values for other than above mentioned registers and
RAM contents are indefinite at reset, they must be set.
Fig. 67 Internal status at reset
68
Address Register contents
X X XX X 1 X X
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
CLOCK GENERATING CIRCUIT
(2) Wait mode
The 3885 group has two built-in oscillation circuits. An oscillation
circuit can be formed by connecting a resonator between XIN and
XOUT (XCIN and XCOUT). Use the circuit constants in accordance
with the resonator manufacturer’s recommended values. No external resistor is needed between XIN and XOUT since a feed-back
resistor exists on-chip. However, an external feed-back resistor is
needed between XCIN and XCOUT.
Immediately after power on, only the XIN oscillation circuit starts
oscillating, and XCIN and XCOUT pins function as I/O ports.
If the WIT instruction is executed, the internal clock φ stops at an
“H” level, but the oscillator does not stop. The internal clock φ restarts at reset or when an interrupt is received. Since the oscillator
does not stop, normal operation can be started immediately after
the clock is restarted.
Frequency Control
(1) Middle-speed mode
XCIN
The internal clock φ is the frequency of XIN divided by 8. After reset, this mode is selected.
XCOUT
Rf
(2) High-speed mode
CCIN
XIN
XOUT
Rd
CCOUT
CIN
COUT
The internal clock φ is half the frequency of XIN.
(3) Low-speed mode
Fig. 68 Ceramic resonator circuit
The internal clock φ is half the frequency of XCIN.
■Note
If you switch the mode between middle/high-speed and lowspeed, stabilize both XIN and XCIN oscillations. The sufficient time
is required for the sub clock to stabilize, especially immediately after power on and at returning from stop mode. When switching the
mode between middle/high-speed and low-speed, set the frequency on condition that f(XIN) > 3f(XCIN).
(4) Low power dissipation mode
The low power consumption operation can be realized by stopping
the main clock XIN in low-speed mode. To stop the main clock, set
bit 5 of the CPU mode register to “1”. When the main clock XIN is
restarted (by setting the main clock stop bit to “0”), set sufficient
time for oscillation to stabilize.
XCIN
XCOUT
XIN
XOUT
Open
Open
External oscillation
circuit
External oscillation
circuit
VCC
VSS
VCC
VSS
Fig. 69 External clock input circuit
Oscillation Control
(1) Stop mode
If the STP instruction is executed, the internal clock φ stops at an
“H” level, and XIN and X CIN oscillators stop. When the oscillation
stabilizing time set after STP instruction released bit is “0,” the
prescaler 12 is set to “FF16” and timer 1 is set to “0116”. When the
oscillation stabilizing time set after STP instruction released bit is
“1”, set the sufficient time for oscillation of used oscillator to stabilize since nothing is set to the prescaler 12 and timer 1.
Either XIN or XCIN divided by 16 is input to the prescaler 12 as
count source, and the output of the prescaler 12 is connected to
timer 1. Set the timer 1 interrupt enable bit to disabled (“0”) before
executing the STP instruction. Oscillator restarts when an external
interrupt is received, but the internal clock φ is not supplied to the
CPU (remains at “H”) until timer 1 underflows. The internal clock φ
is supplied for the first time, when timer 1 underflows. Therefore
make sure not to set the timer 1 interrupt request bit to “1” before
the STP instruction stops the oscillator. When the oscillator is restarted by reset, apply “L” level to the RESET pin until the
oscillation is stable since a wait time will not be generated.
69
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
XCOUT
XCIN
“0”
“1”
Port XC
switch bit
XOUT
XIN
Main clock division ratio
selection bits (Note 1)
Low-speed mode
1/2
1/4
Prescaler 12
1/2
High-speed or
middle-speed
mode
Timer 1
Reset or
0116 STP instruction
FF16
(Note 2)
Main clock division ratio
selection bits (Note1)
Middle-speed mode
Timing φ (internal clock)
High-speed or
low-speed mode
Main clock stop bit
Q
S
R
S Q
STP instruction
WIT instruction
R
Q S
R
STP instruction
Reset
Interrupt disable flag l
Interrupt request
Notes 1: Either high-speed, middle-speed or low-speed mode is selected by bits 7 and 6 of the CPU mode register.
When low-speed mode is selected, set port Xc switch bit (b4) to “1”.
2: f(XIN)/16 is supplied as the count source to the Prescaler 12 at reset. When exciting STP instruction, the count source
does not change either f(XIN))/16 or f(XCIN))/16 after releasing stop mode. Oscillation stabilizing time is not fixed “01FF16”
when the bit 6 of PCTL2 is “1”.
Fig. 70 System clock generating circuit block diagram (Single-chip mode)
70
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Reset
C
“0 M4
CM ”←
“1 6 →“
1”
”←
→
“0
”
”
“0
→
CM ”←
0”
“1 M6 →“
C ”←
“1
4
CM6
“1”←→“0”
C
“0 M7
CM ”←→
“1 6
“1
”←
”
→
“0
”
CM4
“1”←→“0”
CM4
“1”←→“0”
CM7=0
CM6=1
CM5=0(8 MHz oscillating)
CM4=0(32 kHz stopped)
Middle-speed mode
(f(φ)=1 MHz)
CM7=0
CM6=1
CM5=0(8 MHz oscillating)
CM4=1(32 kHz oscillating)
High-speed mode
(f(φ)=4 MHz)
CM7=0
CM6=0
CM5=0(8 MHz oscillating)
CM4=0(32 kHz stopped)
CM6
“1”←→“0”
High-speed mode
(f(φ)=4 MHz)
CM7=0
CM6=0
CM5=0(8 MHz oscillating)
CM4=1(32 kHz oscillating)
CM7
“1”←→“0”
Middle-speed mode
(f(φ)=1 MHz)
Low-speed mode
(f(φ)=16 kHz)
CM5
“1”←→“0”
CM7=1
CM6=0
CM5=0(8 MHz oscillating)
CM4=1(32 kHz oscillating)
Low-speed mode
(f(φ)=16 kHz)
CM7=1
CM6=0
CM5=1(8 MHz stopped)
CM4=1(32 kHz oscillating)
b7
b4
CPU mode register
(CPUM : address 003B16)
CM4 : Port Xc switch bit
0 : I/O port function (stop oscillating)
1 : XCIN-XCOUT oscillating function
CM5 : Main clock (XIN- XOUT) stop bit
0 : Operating
1 : Stopped
CM7, CM6: Main clock division ratio selection bit
b7 b6
0 0 : φ = f(XIN)/2 ( High-speed mode)
0 1 : φ = f(XIN)/8 (Middle-speed mode)
1 0 : φ = f(XCIN)/2 (Low-speed mode)
1 1 : Not available
Notes 1 : Switch the mode by the allows shown between the mode blocks. (Do not switch between the modes directly without an allow.)
2 : The all modes can be switched to the stop mode or the wait mode and return to the source mode when the stop mode or the wait mode is
ended.
3 : Timer operates in the wait mode.
4 : When the stop mode is ended, a delay of approximately 1 ms occurs by connecting prescaler 12 and Timer 1 in middle/high-speed mode.
5 : When the stop mode is ended, a delay of approximately 0.25 s occurs by Timer 1 and Timer 2 in low-speed mode.
6 : Wait until oscillation stabilizes after oscillating the main clock XIN before the switching from the low-speed mode to middle/high-speed
mode.
7 : The example assumes that 8 MHz is being applied to the XIN pin and 32 kHz to the XCIN pin. φ indicates the internal clock.
Fig. 71 State transitions of system clock
71
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
FLASH MEMORY MODE
The 3885 (flash memory version) has an internal new DINOR
flash memory that can be reprogrammed with 2 power sources
when VCC is 3.3 V.
For this flash memory , two flash memory modes are available in
which to read, program, and erase: parallel I/O and a CPU reprogram mode in which the flash memory can be manipulated by the
Central Processing Unit (CPU). Each mode is detailed in the
pages to follow.
The flash memory of the 3885 is divided into User ROM area and
Boot ROM area as shown in Figure 72.
In addition to the ordinary user ROM area to store a microcomputer operation control program, 3885 program has a Boot ROM
area that is used to store a program to control reprogramming in
CPU reprogram mode. The user can store a reprogram control
software in this area that suits the user’s application system. This
Boot ROM area can be reprogrammed in only parallel I/O mode.
Parallel I/O mode
100016
Block 1 : 28 Kbyte
800016
Block 0 : 32Kbyte
FFFF16
F00016
4 Kbyte
FFFF16
User ROM area
Boot ROM area
BSEL = 0
BSEL = 1
CPU reprogram mode
100016
Block 1 : 28 Kbyte
800016
Block 0 : 32 Kbyte
Product name
Flash memory
start address
M38859FF
100016
FFFF16
F00016
4 Kbyte
FFFF16
User ROM area
User area / Boot area selection bit = 0
Boot ROM area
User area / Boot area selection bit = 1
Notes 1: The Boot ROM area can be rewritten in only parallel input/
output mode.
2: To specify a block, use the maximum address in the block.
Fig. 72 Block diagram of flash memory version
72
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Parallel I/O Mode
Bus Operation Modes
The parallel I/O mode is entered by making connections shown in
Figures 73 and then turning the Vcc power supply on.
Read
Address
The user ROM is divided into two blocks as shown in Figure 72. The
block address referred to in this data sheet is the maximum address
value of each block.
User ROM and Boot ROM Areas
In parallel I/O mode, the user ROM and boot ROM areas shown in Figure 72 can be rewritten. The BSEL pin is used to choose between these
two areas. The user ROM area is selected by pulling the BSEL input
low; the boot ROM area is selected by driving the BSEL input high. Both
areas of flash memory can be operated on in the same way.
Program and block erase operations can be performed in the user ROM
area. The user ROM area and its blocks are shown in Figure 72.
The user ROM area is 60 Kbytes in size. In parallel I/O mode, it is
located at addresses 100016 through FFFF16. The boot ROM area is
4 Kbytes in size. In parallel I/O mode, it is located at addresses
F00016 through FFFF16. Make sure program and block erase operations are always performed within this address range. (Access to any
location outside this address range is prohibited.)
In the Boot ROM area, an erase block operation is applied to only
one 4 Kbyte block.
Functional Outline (Parallel I/O Mode)
In parallel I/O mode, bus operation modes—Read, Output Disable,
Standby, Write, and Deep Power Down—are selected by the status
_____ _____ _____
_____
of the CE, OE, WE, and RP input pins.
The contents of erase, program, and other operations are selected
by writing a software command. The data, status register, etc. in
memory can only be read out by a read after software command
input.
Program and erase operations are controlled using software commands.
The following explains about bus operation modes, software commands, and status register.
_____
_____
The Read mode is entered by pulling the OE pin low when the CE
_____
_____
pin is low and the WE and RP pins are high. There are two read
modes: array, and status register, which are selected by software
command input. In read mode, the data corresponding to each software command entered is output from the data I/O pins D0–D7. The
read array mode is automatically selected when the device is powered on or after it exits deep power down mode.
Output Disable
_____
The output disable mode is entered by pulling the CE pin low and the
_____ _____
_____
WE, OE, and RP pins high. Also, the data I/O pins are placed in the
high-impedance state.
Standby
_____
_____
The standby mode is entered by driving the CE pin high when the RP
pin is high. Also, the data I/O pins are placed in the high-impedance
_____
state. However, if the CE pin is set high during erase or program
operation, the internal control circuit does not halt immediately and
normal power consumption is required until the operation under way
is completed.
Write
_____
_____
The write mode is entered by pulling the WE pin low when the CE pin
_____
_____
is low and the OE and RP pins are high. In this mode, the device
accepts the software commands or write data entered from the data
I/O pins. A program, erase, or some other operation is initiated depending on the content of the software command entered here. The
input data such as address and software command is latched at the
_____
_____
rising edge of WE or CE whichever occurs earlier.
Deep Power Down
_____
The deep power down is entered by pulling the RP pin low. Also, the
data I/O pins are placed in the high-impedance state. When the device is freed from deep power down mode, the read array mode is
selected and the content of the status register is set to “8016.” If the
_____
RP pin is pulled low during erase or program operation, the operation under way is canceled and the data in the relevant block becomes invalid.
Table 19 Relationship between control signals and bus operation modes
Pin name
_____
_____
______
_____
CE
OE
WE
RP
Array
VIL
VIL
VIH
VIH
Data output
Status register
VIL
VIL
VIL
VIH
VIH
VIH
VIH
VIH
Status register data output
Hi-z
Program
VIH
VIL
X
VIH
X
VIL
VIH
VIH
Hi-z
Command/data input
Erase
Other
VIL
VIL
VIH
VIH
VIL
VIL
VIH
VIH
Command input
Command input
X
X
X
VIL
Hi-z
Mode
Read
Output disabled
Stand by
Write
Deep power down
D0 to D7
Note : X can be VIL or VIH.
73
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 20 Description of Pin Function (Flash Memory Parallel I/O Mode)
Pin name
Signal name
Function
I/O
VCC,VSS
Power supply input
I
Apply 3.0 ± 0.3 V to the Vcc pin and 0 V to the Vss pin.
CNVSS
Power suppy input
I
Connect to Vpp = 5V ± 0.5V.
RESET
Reset input
I
Input “L” level.
XIN
Clock input
I
XOUT
Clock output
O
Connect a ceramic or crystal resonator between the XIN and XOUT pins.
When entering an externally derived clock, enter it from XIN and leave
XOUT open.
AVSS
Analog power supply input
I
Connect to Vss.
VREF
Reference voltage input
I
Connect to Vss.
P00 to P07
Address input A0 to A7
I
This is address A0–A7 input pins.
P10 to P17
Address input A8 to A15
I
These are address A8–A15 input pins.
P20 to P27
Data I/O D0 to D7
P30
Input P30
I
Input “H” or “L” or keep open.
P31
BSEL input
I
This is a BSEL input pin.
P32
Input P32
I
Input “H” or “L” or keep open.
P33
WE input
I
This is a WE input pin.
P34
RP input
I
This is a RP input pin.
P35
RY/BY output
O
This is a RY/BY output pin.
P36
CE input
I
This is a CE input pin.
P37
OE input
I
This is a OE input pin.
P40 to P45
Input P40 to P45
I
Input “H” or “L” or keep open.
P46
Flash mode Input
I
Connect “L” for Pallarel I/O mode.
P47
Input P47
I
Input “H” or “L” or keep open.
P50 to P57
Input P5
I
Input “H” or “L” or keep open.
P60 to P67
Input P6
I
Input “H” or “L” or keep open.
P70 to P77
Input P7
I
Input “H” or “L” or keep open.
P80 to P87
Input P8
I
Input “H” or “L” or keep open.
74
I/O
These are data D0–D7 input/output pins.
MITSUBISHI MICROCOMPUTERS
3885 Group
A13
A11
A12
A10
A7
A8
A9
A5
A6
A3
A4
A2
A0
A1
CE
OE
RP
41
44
43
42
46
45
50
49
48
47
40
61
62
63
64
65
66
67
68
69
70
39
38
37
36
35
34
33
32
31
30
29
28
M38859FFHP
71
72
73
74
75
76
77
78
79
80
A14
A15
D0
D1
D2
D3
D4
D5
D6
D7
Vss
*
Vpp
20
19
18
17
16
15
14
13
12
11
9
10
6
7
8
4
5
P16
P17/CMPREF
P20
P21
P22
P23
P24(LED0)
P25(LED1)
P26(LED2)
P27(LED3)
VSS
XOUT
XIN
P40/XCOUT
P41/XCIN
RESET
CNVSS
P42/INT0
P43/INT1
P44/RXD
P60/AN0
P77/SCL
P76/SDA
P75/INT41
P74/INT31
P73/INT21
P72
P71
RY/BY
P70
P57/DA2/PWM11
P56/DA1/PWM01
P55/CNTR1
P54/CNTR0
P53/INT40
P52/INT30
P51/INT20
P50/INT5
P47/SRDY/CLKRUN#
P46/SCLK
P45/TXD
3
27
26
25
24
23
22
21
1
Vcc
P31/PWM10
P30/PWM00
P87/SERIRQ
P86/LCLK
P85/LRESET#
P84/LFRAME#
P83/LAD3
P82/LAD2
P81/LAD1
P80/LAD0
VCC
VREF
AVSS
P67/AN7
P66/AN6
P65/AN5
P64/AN4
P63/AN3
P62/AN2
P61/AN1
2
BSEL
57
56
55
54
53
52
51
60
59
58
P32
P33
P34
P35
P36
P37
P00
P01
P02
P03
P04
P05
P06
P07
P10
P11
P12
P13
P14
P15
WE
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Mode setup method
Signal
CNVSS
P46/SCLK
RESET
✽ :Connect to the ceramic oscillation circuit.
indicates the flash memory pin.
Value
Vpp
VSS
VSS
Fig. 73 Pin connection diagram in parallel I/O mode
75
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Software Commands
Read Status Register Command (7016)
Table 21 lists the software commands. By entering a software command from the data I/O pins (D0–D7) in Write mode, specify the content of the operation, such as erase or program operation, to be performed.
The following explains the content of each software command.
When the command code “7016” is written in the first bus cycle, the
content of the status register is output from the data I/O pins (D0–D7)
by a read in the second bus cycle. Since the content of the status
_____
_____
_____
_____
register is updated at the falling edge of OE or CE, the OE or CE
signal must be asserted each time the status is read. The status
register is explained in the next section.
Read Array Command (FF16)
The read array mode is entered by writing the command code “FF16”
in the first bus cycle. When an address to be read is input in one of
the bus cycles that follow, the content of the specified address is
output from the data I/O pins (D0–D7).
The read array mode is retained intact until another command is written.
The read array mode is also selected automatically when the device
is powered on and after it exits deep power down mode.
Clear Status Register Command (5016)
This command is used to clear the bits SR4,SR5 of the status register after they have been set. These bits indicate that operation has
ended in an error. To use this command, write the command code
“5016” in the first bus cycle.
Table 21 Software command list (parallel I/O mode)
Second bus cycle
First bus cycle
Command
Cycle number
Mode
(D0 to D7)
Mode
Data
Address
(D0 to D7)
X
SRD(Note 1)
Read array
Read status register
1
2
Write
Write
X(Note 4)
X
FF16
7016
Read
Clear status register
Program
1
2
Write
Write
X
X
5016
4016
Write
WA(Note 2) WD(Note 2)
Block erase
2
Write
X
2016
Write
BA(Note 3)
Notes 1: SRD = Status Register Data
2: WA = Write Address, WD = Write Data
3: BA = Block Address (Enter the maximum address of each block)
4: X denotes a given address in the user ROM area or boot ROM area.
76
Data
Address
D016
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Program Command (4016)
Block Erase Command (2016/D016)
The program operation starts when the command code “4016” is written in the first bus cycle. Then, if the address and data to program
are written in the 2nd bus cycle, program operation (data programming and verification) will start.
Whether the write operation is completed can be confirmed by read_____
ing the status register or the RY/BY signal status. When the program
starts, the read status register mode is accessed automatically and
the content of the status register can be read out from the data bus
(D0–D7). The status register bit 7 (SR7) is set to “0” at the same time
the write operation starts and is returned to “1” upon completion of
the write operation. In this case, the read status register mode remains active until the read array command (FF16) is written.
____
The RY/BY pin is “L” during write operation and “H” when the write
operation is completed as is the status register bit 7.
At program end, program results can be checked by reading the status register.
By writing the command code “2016” in the first bus cycle and the
confirmation command code “D016” in the second bus cycle that
follows to the block address of a flash memory block, the system
initiates a block erase (erase and erase verify) operation.
Whether the block erase operation is completed can be confirmed
____
by reading the status register or the RY/BY signal. At the same time
the block erase operation starts, the read status register mode is
automatically entered, so the content of the status register can be
read out. The status register bit 7 (SR7) is set to “0” at the same time
the block erase operation starts and is returned to “1” upon completion of the block erase operation. In this case, the read status register mode remains active until the read array command (FF16) is written.
____
The RY/BY pin is “L” during block erase operation and “H” when the
block erase operation is completed as is the status register bit 7.
After the block erase operation is completed, the status register can
be read out to know the result of the block erase operation. For details, refer to the section where the status register is detailed.
Start
Start
Write 4016
Write 2016
Write Write address
Write data
Write
Status register
read
SR7=1?
or
RY/BY=1?
D016
Block address
Status register
read
NO
SR7=1?
or
RY/BY=1?
NO
YES
YES
NO
SR4=0?
Program
error
NO
SR5=0?
Erase error
YES
Program
completed
In this case, the read status
register mode remains
active until the read array
command (FF16) is written.
Fig. 74 Page program flowchart
YES
Erase completed
In this case, the read status
register mode remains active
until the read array command
(FF16) is written.
Fig. 75 Block erase flowchart
77
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Status Register
Program Status (SR4)
The status register indicates status such as whether an erase operation or a program ended successfully or in error. It can be read under
the following conditions.
(1) In the read array mode when the read status register command
(7016) is written and the block address is subsequently read.
(2) In the period from when the program write or auto erase starts to
when the read array command (FF16)
The program status reports the operating status of the write operation. If a write error occurs, it is set to “1”. When the program status is
cleared, it is set to “0”.
If “1” is written for any of the SR5, SR4 bits, the program erase all
blocks, block erase, commands are not accepted. Before executing
these commands, execute the clear status register command (5016)
and clear the status register.
Also, any commands are not correct, both SR5 and SR4 are set to
“1”.
The status register is cleared in the following situations.
(1) By writing the clear status register command (5016)
(2) In the deep power down mode
(3) In the power supply off state
Table 22 gives the definition of each status register bit. When power
is turned on or returning from the deep power down mode, the status
register outputs “8016”.
Full Status Check
Results from executed erase and program operations can be known
by running a full status check. Figure 76 shows a flowchart of the full
status check and explains how to remedy errors which occur.
____
Ready/Busy (RY/BY) pin
____
Sequencer status (SR7)
The sequencer status indicates the operating status of the flash
memory. When power is turned on or returning from the deep power
down mode, “1” is set for it. This bit is “0” (busy) during the write or
erase operations and becomes “1” when these operations ends.
The RY/BY pin is an output pin (N-chanel open drain output) which,
like the sequencer status (SR7), indicates the operating status of the
flash memory. It is “L” level during auto program or auto erase operations and becomes to the high impedance state (ready state) when
____
these operations end. The RY/BY pin requires an external pull-up.
Erase Status (SR5)
The erase status reports the operating status of the erase operation.
If an erase error occurs, it is set to “1”. When the erase status is
cleared, it is set to “0”.
Table 22 Status register
78
Each bit of
SRD0 bits
SR7 (D7)
Sequencer status
SR6 (D6)
SR5 (D5)
Status name
Definition
“1”
“0”
Ready
Busy
Reserved
Erase status
Ended in error
Ended successfully
SR4 (D4)
SR3 (D3)
Program status
Reserved
Ended in error
-
Ended successfully
-
SR2 (D2)
SR1 (D1)
Reserved
Reserved
-
-
SR0 (D0)
Reserved
-
-
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Read status register
SR4=1 and SR5
=1 ?
YES
Command
sequence error
NO
SR5=0?
NO
Block erase error
Execute the clear status register command (5016)
to clear the status register. Try performing the
operation one more time after confirming that the
command is entered correctly.
Should a block erase error occur, the block in error
cannot be used.
YES
SR4=0?
NO
Program error
Should a program error occur, the block in error
cannot be used.
YES
End (block erase, program)
Note: When one of SR5 to SR4 is set to “1” , none of the program, all blocks erase, or block erase
is accepted. Execute the clear status register command (5016) before executing these commands.
Fig. 76 Full status check flowchart and remedial procedure for errors
79
MITSUBISHI MICROCOMPUTERS
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CPU Reprogram Mode
In CPU reprogram mode, the on-chip flash memory can be operated
on (read, program, or erase) under control of the Central Processing
Unit (CPU).
In CPU reprogram mode, only the user ROM area shown in Figure
72 can be reprogrammed; the Boot ROM area cannot be reprogrammed. Make sure the program and block erase commands are
issued for only the user ROM area.
The control program for CPU reprogram mode can be stored in either user ROM or Boot ROM area. In the CPU reprogram mode,
because the flash memory cannot be read from the CPU, the reprogram control software must be transferred to internal RAM area before it can be executed.
Microcomputer Mode and Boot Mode
The control software for CPU reprogram mode must be programed
into the user ROM or Boot ROM area in parallel I/O mode beforehand. (If the control software is programed into the Boot ROM area,
the standard serial I/O mode becomes unusable.)
See Figure 72 for details about the Boot ROM area.
Normal microcomputer mode is entered when the microcomputer is
released from reset with pulling CNVSS pin low. In this case, the
CPU starts operating using the control software in the user ROM
area.
When the microcomputer is released from reset by pulling the P46/
SCLK pin high, the CNVSS pin high, the CPU starts operating using
the control software in the Boot ROM area (program start address
should be stored FFFC16, FFFD16). This mode is called the “boot
mode”.
Block Address
Block addresses refer to the maximum address of each block. These
addresses are used in the block erase command. In case of the
M38859FF, these are two block.
Outline Performance (CPU Reprogram Mode)
In the CPU reprogram mode, the CPU erases, programs and reads
the internal flash memory as instructed by software commands. This
reprogram control software must be transferred to internal RAM before it can be executed.
The CPU reprogram mode is accessed by applying 5V ± 10% to the
CNVSS pin and writing “1” for the CPU reprogram mode select bit (bit
1 in address 0FFE16). Software commands are accepted once the
mode is accessed.
Use software commands to control software and erase operations.
Whether a program or erase operation has terminated normally or in
error can be verified by reading the status register.
Figure 77 shows the flash memory control register.
_____
Bit 0 is the RY/BY status flag used exclusively to read the operating
status of the flash memory. During programming and erase operations, it is “0”. Otherwise, it is “1”.
Bit 1 is the CPU reprogram mode select bit. When this bit is set to “1”
and 5V ± 10% are applied to the CNVSS pin, the M38859FF enters
the CPU reprogram mode. Software commands are accepted once
the mode is accessed. In CPU reprogram mode, the CPU becomes
unable to access the internal flash memory. Therefore, use the con-
80
trol software in RAM for write to bit 1. To set this bit to “1”, it is necessary to write “0” and then write “1” in succession. The bit can be set
to “0” by only writing a “0”.
Bit 2 is the CPU reprogram mode entry flag. This bit can be read to
check whether the CPU reprogram mode has been entered or not.
Bit 3 is the flash memory reset bit used to reset the control circuit of
the internal flash memory. This bit is used when exiting CPU reprogram mode and when flash memory access has failed. When the
CPU reprogram mode select bit is “1”, writing “1” for this bit resets
the control circuit. To release the reset, it is necessary to set this bit
to “0”.
Bit 4 is the User area/Boot area selection bit. When this bit is set to
“1”, Boot ROM area is accessed, and CPU reprogram mode in Boot
ROM area is available. In boot mode, this bit is set “1” automatically.
To set and clear this bit must be operated in RAM area.
Figure 78 shows a flowchart for setting/releasing the CPU reprogram mode.
Notes on CPU Reprogram Mode
Described below are the precautions to be observed when reprogram the flash memory in CPU reprogram mode.
(1) Operation speed
During CPU reprogram mode, set the internal clock φ frequency
4MHz or less using the main clock division ratio selection bits (bit
6,7 at 003B16).
(2) Instructions inhibited against use
The instructions which refer to the internal data of the flash
memory cannot be used during CPU reprogram mode .
(3) Interrupts inhibited against use
The interrupts cannot be used during CPU reprogram mode because they refer to the internal data of the flash memory.
(4) Watchdog timer
In case of the watchdog timer has been running already, the internal reset generated by watchdog timer underflow does not
happen, because of watchdog timer is always clearing during
program or erase operation.
(5) Reset
Reset is always valid. In case of CNVSS = “H” when reset is released, boot mode is active. So the program starts from the address contained in address FFFC16 and FFFD16 in boot ROM
area.
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
b7
b0
Flash memory control register (address 0FFE16)
FMCR
RY/BY status flag (FMCR0)
0: Busy (being programmed or erased)
1: Ready
CPU reprogram mode select bit (FMCR1) (Note 2)
0: Normal mode (Software commands invalid)
1: CPU rewrite mode (Software commands acceptable)
CPU reprogram mode entry flag (FMCR2)
0: Normal mode
1: CPU rewrite mode
Flash memory reset bit (FMCR3) (Note 3)
0: Normal operation
1: Reset
User ROM area / Boot ROM area select bit (FMCR4) (Note 4)
0: User ROM area accessed
1: Boot ROM area accessed
Reserved bits (Indefinite at read/ “0” at write)
Notes 1: The contents of flash memory control register are “XXX00001” just after reset release.
2: For this bit to be set to “1”, the user needs to write “0” and then “1” to it in succession. If it is not
this procedure, this bit will not be set to ”1”. Additionally, it is required to ensure that no interrupt
will be generated during that interval.
Use the control program in the area except the built-in flash memory for write to this bit.
3: This bit is valid when the CPU rewrite mode select bit is “1”. Set this bit 3 to “0” subsequently after
setting bit 3 to “1”.
4: Use the control program in the area except the built-in flash memory for write to this bit.
Fig. 77 Flash memory control registers
Program in ROM
Program in RAM
Start
*1
Single-chip mode, or boot mode
Set CPU reprogram mode select bit to “1” (by
writing “0” and then “1” in succession)(Note 3)
Set CPU mode register (Note 1)
Transfer CPU reprogram mode
control program to internal RAM
Jump to transferred control program in RAM
(Subsequent operations are executed by control
program in this RAM)
Check the CPU reprogram mode entry flag
Using software command execute erase,
program, or other operation
Execute read array command or reset flash
memory by setting flash memory reset bit (by
writing “1” and then “0” in succession) (Note 2)
*1
Write “0” to CPU reprogram mode select bit
End
Notes 1: Set bit 6,7 (Main clock division ratio selection bits ) at CPU mode register (003B16).
2: Before exiting the CPU reprogram mode after completing erase or program operation, always be sure to
execute a read array command or reset the flash memory.
Fig. 78 CPU rewrite mode set/reset flowchart
81
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Software Commands
Read Status Register Command (7016)
Table 23 lists the software commands.
After setting the CPU reprogram mode select bit to “1”, write a software command to specify an erase or program operation.
The content of each software command is explained below.
When the command code “7016” is written in the first bus cycle, the
content of the status register is read out at the data bus (D0–D7) by a
read in the second bus cycle.
The status register is explained in the next section.
Read Array Command (FF16)
Clear Status Register Command (5016)
The read array mode is entered by writing the command code “FF16”
in the first bus cycle. When an address to be read is input in next bus
cycles, the content of the specified address is read out at the data
bus (D0–D7).
The read array mode is retained intact until another command is written. And after power on and after recover from deep power down
mode, this mode is selected also.
This command is used to clear the bits SR1,SR4 and SR5 of the
status register after they have been set. These bits indicate that operation has ended in an error. To use this command, write the command code “5016” in the first bus cycle.
Table 23 List of software commands (CPU rewrite mode)
First bus cycle
Command
Cycle number
Mode
Address
Second bus cycle
Data
(D0 to D7)
Mode
Address
Data
(D0 to D7)
Read
X
SRD (Note 1)
Read array
1
Write
Read status register
2
Write
X
7016
Clear status register
1
Write
X
5016
Program
2
Write
X
4016
Write
WA
Block erase
2
Write
X
2016
Write
BA (Note 3)
X
(Note 4)
Note 1: SRD = Status Register Data
2: WA = Write Address, WD = Write Data
3: BA = Block Address (Enter the maximum address of each block.)
4: X denotes a given address in the user ROM area .
82
F F1 6
(Note 2)
WD
(Note 2)
D016
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Program Command (4016)
Block Erase Command (2016/D016)
Program operation starts when the command code “4016” is written
in the first bus cycle. Then, if the address and data to program are
written in the 2nd bus cycle, program operation (data programming
and verification) will start.
Whether the program operation is completed can be confirmed by
_____
reading the status register or the RY/BY status flag. When the program starts, the read status register mode is accessed automatically
and the content of the status register is read into the data bus (D0–
D7). The status register bit 7 (SR7) is set to “0” at the same time the
program operation starts and is returned to “1” upon completion of
the program operation. In this case, the read status register mode
remains active until the read array command (FF16) is written.
____
The RY/BY status flag is “0” during program operation and “1” when
the program operation is completed as is the status register bit 7.
At program end, program results can be checked by reading the status register.
By writing the command code “2016” in the first bus cycle and the
confirmation command code “D016” in the second bus cycle that
follows to the block address of a flash memory block, the system
initiates a block erase (erase and erase verify) operation.
Whether the block erase operation is completed can be confirmed
____
by reading the status register or the RY/BY status flag. At the same
time the block erase operation starts, the read status register mode
is automatically entered, so the content of the status register can be
read out. The status register bit 7 (SR7) is set to “0” at the same time
the block erase operation starts and is returned to “1” upon completion of the block erase operation. In this case, the read status register mode remains active until the read array command (FF16) is written.
____
The RY/BY status flag is “0” during block erase operation and “1”
when the block erase operation is completed as is the status register
bit 7.
After the block erase operation is completed, the status register can
be read out to know the result of the block erase operation. For details, refer to the section where the status register is detailed.
Start
Start
Write 4016
Write 2016
Write Program address
Program data
Write
Status register
read
SR7=1?
or
RY/BY=1?
Status register
read
NO
SR7=1?
or
RY/BY=1?
YES
SR4=0?
YES
Program
completed
Fig. 79 Program flowchart
D016
Block address
NO
YES
NO
Program
error
SR5=0?
NO
Erase error
YES
Erase completed
Fig. 80 Erase flowchart
83
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Status Register
Sequencer status (SR7)
The status register shows the operating state of the flash memory
and whether erase operations and programs ended successfully or
in error. It can be read in the following ways.
(1) By reading an arbitrary address from the user ROM area after
writing the read status register command (7016)
(2) By reading an arbitrary address from the user ROM area in the
period from when the program starts or erase operation starts to
when the read array command (FF16) is input
After power-on, and after recover from deep power down mode, the
sequencer status is set to “1”(ready).
The sequencer status indicates the operating status of the device.
This status bit is set to “0” (busy) during program or erase operation
and is set to “1” upon completion of these operations.
Table 24 shows the status register.
Also, the status register can be cleared in the following way.
(1) By writing the clear status register command (5016)
(2) In the deep power down mode
(3) In the power supply off state
After a reset, the status register is set to “8016”.
Each bit in this register is explained below.
Erase status (SR5)
The erase status informs the operating status of erase operation to
the CPU. When an erase error occurs, it is set to “1”.
The erase status is reset to “0” when cleared.
Program status (SR4)
The program status informs the operating status of write operation to
the CPU. When a write error occurs, it is set to “1”.
The program status is reset to “0” when cleared.
If “1” is set for any of the SR5 or SR4 bits, the program, erase all
blocks, and block erase commands are not accepted. Before executing these commands, execute the clear status register command (5016) and clear the status register.
Also, any commands are not correct, both SR5 and SR4 are set to
“1”.
Table 24 Definition of each bit in status register
84
Each bit of
SRD0 bits
SR7 (bit7)
Sequencer status
SR6 (bit6)
SR5 (bit5)
Status name
Definition
“1”
“0”
Ready
Busy
Reserved
Erase status
Terminated in error
Terminated normally
SR4 (bit4)
SR3 (bit3)
Program status
Reserved
Terminated in error
-
Terminated normally
-
SR2 (bit2)
SR1 (bit1)
Reserved
Reserved
-
-
SR0 (bit0)
Reserved
-
-
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Full Status Check
By performing full status check, it is possible to know the execution
results of erase and program operations. Figure 81 shows a full status check flowchart and the action to be taken when each error occurs.
Read status register
SR4=1 and SR5
=1 ?
YES
Command
sequence error
NO
SR5=0?
NO
Block erase error
Execute the clear status register command (5016)
to clear the status register. Try performing the
operation one more time after confirming that the
command is entered correctly.
Should a block erase error occur, the block in error
cannot be used.
YES
SR4=0?
NO
Program error
Should a program error occur, the block in error
cannot be used.
YES
End (block erase, program)
Note: When one of SR5 to SR4 is set to “1” , none of the program, erase all blocks,
and block erase commands is accepted. Execute the clear status register
command (5016) before executing these commands.
Fig. 81 Full status check flowchart and remedial procedure for errors
85
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Functions To Inhibit Rewriting Flash Memory
To prevent the contents of the flash memory data from being read
out or rewritten easily, the device incorporates a ROM code protect
function for use in parallel I/O mode.
ROM code protect function
The ROM code protect function is the function inhibit reading out or
modifying the contents of the flash memory version by using the
ROM code protect control address (FFDB16) during parallel I/O
mode. Figure 82 shows the ROM code protect control address
(FFDB16). (This address exists in the user ROM area.)
If one of the pair of ROM code protect bits is set to “0”, ROM code
b7
protect is turned on, so that the contents of the flash memory data
are protected against readout and reprogram. ROM code protect is
implemented in two levels. If level 2 is selected, the flash memory is
protected even against readout by a manufactures inspection test
also. When an attempt is made to select both level 1 and level 2,
level 2 is selected by default.
If both of the two ROM code protect reset bits are set to “00”, ROM
code protect is turned off, so that the contents of the flash memory
data can be read out or reprogram. Once ROM code protect is
turned on, the contents of the ROM code protect reset bits cannot
be modified in parallel I/O mode. Use CPU reprogram mode to reprogram the contents of the ROM code protect reset bits.
b0
1 1 ROM code protect control (address FFDB16) (Note 1)
ROMCP
Reserved bits (“1” at read/write)
ROM code protect level 2 set bits (ROMCP2) (Notes 2, 3)
b3b2
0 0: Protect enabled
0 1: Protect enabled
1 0: Protect enabled
1 1: Protect disabled
ROM code protect reset bits (ROMCR) (Note 4)
b5b4
0 0: Protect removed
0 1: Protect set bits effective
1 0: Protect set bits effective
1 1: Protect set bits effective
ROM code protect level 1 set bits (ROMCP1) (Note 2)
b7b6
0 0: Protect enabled
0 1: Protect enabled
1 0: Protect enabled
1 1: Protect disabled
Notes 1: The contents of ROM code protect control register are “FF16” just after reset
release. This area is on the ROM in the mask ROM version.
2: When ROM code protect is turned on, the internal flash memory is protected
against readout or modification in parallel I/O mode.
3: When ROM code protect level 2 is turned on, ROM code readout by a shipment
inspection LSI tester, etc. also is inhibited.
4: The ROM code protect reset bits can be used to turn off ROM code protect level 1
and ROM code protect level 2. However, since these bits cannot be modified in
parallel I/O mode, they need to be rewritten in standard serial I/O mode or CPU
rewrite mode.
Fig. 82 ROM code protect control address
86
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Flash Memory Electrical Characteristics
Table 25 Flash memory mode Electrical characteristics
(Ta = 25oC, Vcc = 3.3 ± 0.3V unless otherwise noted)
Limits
Symbol
IPP1
IPP2
IPP3
VIL
VIH
VPP
Parameter
VPP power source current (read)
VPP power source current (program)
VPP power source current (erase)
“L” input voltage (Note)
“H” input voltage (Note)
VPP power source voltage
Test conditions
Min.
0
2.0
4.5
Typ.
Max.
100
60
30
0.8
VCC
5.5
Unit
µA
mA
mA
V
V
V
Note: Input pins for parallel I/O mode.
87
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NOTES ON PROGRAMMING
Processor Status Register
The contents of the processor status register (PS) after a reset are
undefined, except for the interrupt disable flag (I) which is “1”. After a reset, initialize flags which affect program execution. In
particular, it is essential to initialize the index X mode (T) and the
decimal mode (D) flags because of their effect on calculations.
Interrupts
The contents of the interrupt request bits do not change immediately after they have been written. After writing to an interrupt
request register, execute at least one instruction before performing a BBC or BBS instruction.
Decimal Calculations
• To calculate in decimal notation, set the decimal mode flag (D)
to “1”, then execute an ADC or SBC instruction. After executing
an ADC or SBC instruction, execute at least one instruction before executing a SEC, CLC, or CLD instruction.
• In decimal mode, the values of the negative (N), overflow (V),
and zero (Z) flags are invalid.
Serial I/O
In clock synchronous serial I/O, if the receive side is using an external clock and it is to output the S RDY signal, set the transmit
enable bit, the receive enable bit, and the SRDY output enable bit
to “1”.
Serial I/O continues to output the final bit from the TX D pin after
transmission is completed.
In clock-synchronous mode, an external clock is used as synchronous clock, write transmission data to the transmit buffer register
during transfer clock is “H”.
A-D Converter
The comparator uses capacitive coupling amplifier whose charge
will be lost if the clock frequency is too low.
Therefore, make sure that f(XIN) is at least on 500 kHz during an
A-D conversion.
Do not execute the STP or WIT instruction during an A-D conversion.
D-A Converter
When a D-A converter is not used, set all values of D-Ai conversion registers (i=1, 2) to “0016”.
Timers
Instruction Execution Time
If a value n (between 0 and 255) is written to a timer latch, the frequency division ratio is 1/(n+1).
The instruction execution time is obtained by multiplying the period of the internal clock φ by the number of cycles needed to
execute an instruction.
The number of cycles required to execute an instruction is shown
in the list of machine instructions.
The period of the internal clock φ is twice of the XIN period in highspeed mode.
Multiplication and Division Instructions
• The index X mode (T) and the decimal mode (D) flags do not affect the MUL and DIV instruction.
• The execution of these instructions does not change the contents of the processor status register.
Ports
The contents of the port direction registers cannot be read. The
following cannot be used:
• The data transfer instruction (LDA, etc.)
• The operation instruction when the index X mode flag (T) is “1”
• The instruction with the addressing mode which uses the value
of a direction register as an index
• The bit-test instruction (BBC or BBS, etc.) to a direction register
• The read-modify-write instructions (ROR, CLB, or SEB, etc.) to
a direction register.
Use instructions such as LDM and STA, etc., to set the port direction registers.
88
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NOTES ON USAGE
Handling of Power Source Pins
In order to avoid a latch-up occurrence, connect a capacitor suitable for high frequencies as bypass capacitor between power
source pin (V CC pin) and GND pin (V SS pin), between power
source pin (VCC pin) and analog power source input pin (AVSS
pin), and between program power source pin (CNVss/V PP) and
GND pin for flash memory version when on-board reprogramming
is executed. Besides, connect the capacitor to as close as possible. For bypass capacitor which should not be located too far
from the pins to be connected, a ceramic capacitor of 0.01 µF–0.1 µF
is recommended.
Flash Memory Version
The CNVSS pin is connected to the internal memory circuit block
by a low-ohmic resistance, since it has the multiplexed function to
be a programmable power source pin (VPP pin) as well.
To improve the noise reduction, connect a track between CNVSS
pin and VSS pin with 1 to 10 kΩ resistance.
For the mask ROM version, there is no operational interference
even if CNVSS pin is connected to Vss pin via a resistor.
Electric Characteristic Differences Between
Mask ROM and Flash Memory Version MCUs
There are differences in electric characteristics, operation margin,
noise immunity, and noise radiation between Mask ROM and
Flash Memory version MCUs due to the difference in the manufacturing processes.
When manufacturing an application system with the Flash
Memory version and then switching to use of the Mask ROM version, please perform sufficient evaluations for the commercial
samples of the Mask ROM version.
DATA REQUIRED FOR MASK ORDERS
The following are necessary when ordering a mask ROM production:
1. Mask ROM Order Confirmation Form
2. Mark Specification Form
3. Data to be written to ROM, in EPROM form (three identical copies) or one floppy disk.
For the mask ROM confirmation and the mark specifications, refer
to the “Mitsubishi MCU Technical Information” Homepage:
http://www.infomicom.maec.co.jp/indexe.htm
89
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ELECTRICAL CHARACTERISTICS
Table 26 Absolute maximum ratings
Symbol
VCC
VI
VI
VI
VI
VO
VO
Pd
Topr
Tstg
Parameter
Power source voltages
Input voltage P00–P07, P10–P17, P20–P27,
P30–P37, P40–P47, P50–P57,
P60–P67, P80–P87, VREF
RESET, XIN
Input voltage P70–P77
Input voltage CNVSS (Note 1)
Input voltage CNVSS (Note 2)
Output voltage P00–P07, P10–P17, P20–P27,
P30–P37, P40–P47, P50–P57,
P60–P67, P80–P87, XOUT
Output voltage P70–P77
Power dissipation
Operating temperature
Storage temperature
Conditions
All voltages are based on VSS.
Output transistors are cut off.
Ratings
–0.3 to 4.6
Unit
V
–0.3 to VCC +0.3
V
–0.3 to 5.8
–0.3 to 6.5
–0.3 to VCC +0.3
V
V
V
–0.3 to VCC +0.3
V
–0.3 to 5.8
500
–20 to 85
–40 to 125
V
mW
°C
°C
Ta = 25 °C
Notes 1: Flash memory version
2: Mask ROM version
Table 27 Recommended operating conditions
(VCC = 3.3 V ± 0.3V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
Parameter
VCC
Power source voltage
VSS
Power source voltage
VREF
Analog reference voltage
Min.
3.0
Limits
Typ.
3.3
Max.
3.6
0
AVSS
Analog power source voltage
VIA
A-D converter input voltage
AN0–AN7
VIH
“H” input voltage
VIH
“H” input voltage
VIH
“H” input voltage (when TTL input level is selected)
P70–P75
VIH
Unit
V
V
when A-D converter is used
2.0
VCC
when D-A converter is used
2.7
VCC
0
V
V
AVSS
VCC
V
P00–P07, P10–P17, P20–P27, P30–P37, P40–P47,
P50–P57, P60–P67, P80–P87, RESET, CNVSS
0.8VCC
VCC
V
P70–P77
0.8VCC
5.5
V
2.0
5.5
V
“H” input voltage (when I2C-BUS input level is selected)
SDA, SCL
0.7VCC
5.5
V
VIH
“H” input voltage (when SMBUS input level is selected)
SDA, SCL
1.4
5.5
V
VIH
“H” input voltage
XIN, XCIN
0.8VCC
VCC
V
VIL
“L” input voltage
P00–P07, P10–P17, P20–P27, P30–P37, P40–P47,
P50–P57, P60–P67, P70–P77, P80–P87, RESET,
CNVSS
0
0.2VCC
V
VIL
“L” input voltage (when TTL input level is selected)
P70–P75
0
0.8
V
VIL
“L” input voltage (when I2C-BUS input level is selected)
SDA, SCL
0
0.3VCC
V
VIL
“L” input voltage (when SMBUS input level is selected)
SDA, SCL
0
0.6
V
VIL
“L” input voltage
0
0.16VCC
V
90
XIN, XCIN
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 28 Recommended operating conditions
(VCC = 3.3 V ± 0.3V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
ΣIOH(peak)
ΣIOH(peak)
ΣIOL(peak)
ΣIOL(peak)
ΣIOL(peak)
ΣIOH(avg)
ΣIOH(avg)
ΣIOL(avg)
ΣIOL(avg)
ΣIOL(avg)
Parameter
“H” total peak output current
“H” total peak output current
“L” total peak output current
“L” total peak output current
“L” total peak output current
“H” total average output current
“H” total average output current
“L” total average output current
“L” total average output current
“L” total average output current
Min.
Limits
Typ.
P00–P07, P10–P17, P20–P23, P30–P37, P80–P87
P40–P47, P50–P57, P60–P67
P00–P07, P10–P17, P20–P23, P30–P37, P80–P87
P24–P27
P40–P47,P50–P57, P60–P67, P70–P77
P00–P07, P10–P17, P20–P27, P30–P37, P80–P87
P40–P47,P50–P57, P60–P67
P00–P07, P10–P17, P20–P23, P30–P37, P80–P87
P24–P27
P40–P47,P50–P57, P60–P67, P70–P77
Max.
–80
–80
80
80
80
–40
–40
40
40
40
Unit
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
Note : The total output current is the sum of all the currents flowing through all the applicable ports. The total average current is an average value measured
over 100 ms. The total peak current is the peak value of all the currents.
Table 29 Recommended operating conditions
(VCC = 3.3 V ± 0.3V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
Parameter
Min.
Limits
Typ.
Max.
–10
Unit
IOH(peak)
“H” peak output current
P00–P07, P10–P17, P20–P27, P30–P37, P40–P47,
P50–P57, P60–P67, P80–P87 (Note 1)
IOL(peak)
“L” peak output current
P00–P07, P10–P17, P20–P23, P30–P37, P40–P47,
P50–P57, P60–P67, P70–P77, P80–P87 (Note 1)
10
mA
IOL(peak)
“L” peak output current
P24–P27 (Note 1)
20
mA
IOH(avg)
“H” average output current
P00–P07, P10–P17, P20–P27, P30–P37, P40–P47,
P50–P57, P60–P67, P80–P87 (Note 2)
–5
mA
IOL(avg)
“L” average output current
P00–P07, P10–P17, P20–P23, P30–P37, P40–P47,
P50–P57, P60–P67, P70–P77, P80–P87 (Note 2)
5
mA
IOL(avg)
“L” peak output current
P24–P27 (Note 2)
15
mA
f(XIN)
Main clock input oscillation frequency (Note 3)
8
MHz
f(XCIN)
Sub-clock input oscillation frequency (Notes 3, 4)
50
kHz
32.768
mA
Notes 1: The peak output current is the peak current flowing in each port.
2: The average output current IOL(avg), IOH(avg) are average value measured over 100 ms.
3: When the oscillation frequency has a duty cycle of 50%.
4: When using the microcomputer in low-speed mode, set the sub-clock input oscillation frequency on condition that f(XCIN) < f(XIN)/3.
91
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Table 30 Electrical characteristics
(VCC = 3.3 V ± 0.3V, VSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
Limits
Symbol
VOH
VOL
VT+–VT–
IIH
IIH
IIL
IIL
IIL
VRAM
Parameter
“H” output voltage
P00–P07, P10–P17, P20–P27
P30–P37, P40–P47, P50–P57
P60–P67, P80–P87 (Note)
“L” output voltage
P00–P07, P10–P17, P20–P27
P30–P37, P40–P47, P50–P57
P60–P67, P70–P77, P80–P87
Hysteresis
CNTR0, CNTR1, INT0, INT1
INT20–INT40, INT21–INT41, INT5
P30–P37, RxD, SCLK, LRESET
LFRAME, LCLK, SERIRQ
“H” input current
P00–P07, P10–P17, P20–P27
P30–P37, P40–P47, P50–P57
P60–P67, P70–P77, P80–P87
RESET, CNVSS
“H” input current XIN
“L” input current
P00–P07, P10–P17, P20–P27
P30–P37, P40–P47, P50–P57
P60–P67, P70–P77, P80–P87
RESET,CNVSS
“L” input current XIN
“L” input current
P30–P37 (at Pull-up)
RAM hold voltage
Test conditions
IOH = –5 mA
Min.
Max.
VCC–1.0
Unit
V
IOL = 5 mA
1.0
V
IOL = 1.6 mA
0.4
V
V
0.4
VI = VCC
(Pin floating.
Pull-up transistors “off”)
5.0
VI = VCC
VI = VSS
(Pin floating.
Pull-up transistors “off”)
–5.0
VI = VSS
VI = VSS
–13
When clock stopped
2.0
–3
–50
µA
µA
3
Note: P00–P03 are measured when the P00–P03 output structure selection bit (bit 0 of PCTL1) is “0”.
P04–P07 are measured when the P04–P07 output structure selection bit (bit 1 of PCTL1) is “0”.
P10–P13 are measured when the P10–P13 output structure selection bit (bit 2 of PCTL1) is “0”.
P14–P17 are measured when the P14–P17 output structure selection bit (bit 3 of PCTL1) is “0”.
P42, P43, P44, and P46 are measured when the P4 output structure selection bit (bit 2 of PCTL2) is “0”.
P45 is measured when the P45/TXD P-channel output disable bit (bit 4 of UARTCON) is “0”.
92
Typ.
–100
3.6
µA
µA
µA
V
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 31 Electrical characteristics
(VCC = 3.3 V ± 0.3V, VSS = 0 V, Ta = –20 to 85 °C, Mask ROM version unless otherwise noted)
Limits
Symbol
ICC
Parameter
Power source current
Test conditions
High-speed mode
f(XIN) = 8 MHz
f(XCIN) = 32.768 kHz
Output transistors “off”
High-speed mode
f(XIN) = 8 MHz (in WIT state)
f(XCIN) = 32.768 kHz
Output transistors “off”
Middle-speed mode
f(XIN) = 8 MHz
f(XCIN) = stopped
Output transistors “off”
Middle-speed mode
f(XIN) = 8 MHz (in WIT state)
f(XCIN) = stopped
Output transistors “off”
Low-speed mode
f(XIN) = stopped
f(XCIN) = 32.768 kHz
Output transistors “off”
Low-speed mode
f(XIN) = stopped
f(XCIN) = 32.768 kHz (in WIT state)
Output transistors “off”
Additional current when A-D converter
works
f(XIN) = 8 MHz
Additional current when LPC I/F functions
LCLK = 33 MHz
Ta = 25 °C
All oscillation stopped
(in STP state)
Ta = 85 °C
Output transistors “off”
Min.
Unit
Typ.
Max.
2.5
7
mA
0.8
2
mA
1.5
4
mA
0.6
1.5
mA
15
40
µA
10
20
µA
500
µA
1.5
mA
0.1
1.0
µA
10
µA
93
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Table 32 Electrical characteristics
(VCC = 3.3 V ± 0.3V, VSS = 0 V, Ta = –20 to 85 °C, Flash memory version, unless otherwise noted)
Limits
Symbol
ICC
94
Parameter
Power source current
Test conditions
High-speed mode
f(XIN) = 8 MHz
f(XCIN) = 32.768 kHz
Output transistors “off”
High-speed mode
f(XIN) = 8 MHz (in WIT state)
f(XCIN) = 32.768 kHz
Output transistors “off”
Middle-speed mode
f(XIN) = 8 MHz
f(XCIN) = stopped
Output transistors “off”
Middle-speed mode
f(XIN) = 8 MHz (in WIT state)
f(XCIN) = stopped
Output transistors “off”
Low-speed mode
f(XIN) = stopped
f(XCIN) = 32.768 kHz
Output transistors “off”
Low-speed mode
f(XIN) = stopped
f(XCIN) = 32.768 kHz (in WIT state)
Output transistors “off”
Additional current when A-D converter
works
f(XIN) = 8 MHz
Additional current when LPC I/F functions
LCLK = 33 MHz
Ta = 25 °C
All oscillation stopped
(in STP state)
Ta = 85 °C
Output transistors “off”
Min.
Unit
Typ.
Max.
6.0
13
mA
0.8
2
mA
2.0
7
mA
0.6
1.5
mA
100
200
µA
10
20
µA
500
µA
1.5
mA
0.1
1.0
µA
10
µA
MITSUBISHI MICROCOMPUTERS
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Table 33 A-D converter characteristics (1)
(VCC = 3.3 V ± 0.3V, VREF = 2.0 V to VCC, VSS = AVSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
10-bit A-D mode (when conversion mode selection bit (bit 7 of AD2) is “0”)
Symbol
Parameter
–
–
Resolution
Absolute accuracy (excluding quantization error)
Conversion time
Ladder resistor
at A-D converter operated
Reference power
source input current
at A-D converter stopped
tCONV
RLADDER
IVREF
II(AD)
Test conditions
Limits
Min.
Typ.
VCC = VREF = 3.3 V
VREF = 3.3 V
VREF = 3.3 V
12
50
35
150
A-D port input current
Max.
10
±4
61
100
200
5
5.0
Unit
bit
LSB
2tc(XIN)
kΩ
µA
µA
µA
Table 34 A-D converter characteristics (2)
(VCC = 3.3 V ± 0.3V, VREF = 2.0 V to VCC, VSS = AVSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
8-bit A-D mode (when conversion mode selection bit (bit 7 of AD2) is “1”)
Symbol
Parameter
–
–
Resolution
Absolute accuracy (excluding quantization error)
Conversion time
Ladder resistor
at A-D converter operated
Reference power
source input current
at A-D converter stopped
tCONV
RLADDER
IVREF
II(AD)
Test conditions
Limits
Min.
Typ.
VCC = VREF = 3.3 V
VREF = 3.3 V
VREF = 3.3 V
12
50
35
150
A-D port input current
Max.
8
±2
50
100
200
5
5.0
Unit
bit
LSB
2tc(XIN)
kΩ
µA
µA
µA
Table 35 D-A converter characteristics
(VCC = 3.3 V ± 0.3V, VREF = 2.7 V to VCC, VSS = AVSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
–
–
tsu
RO
IVREF
Parameter
Test conditions
Resolution
Absolute accuracy
Setting time
Output resistor
Reference power source input current
Limits
Min.
2
Typ.
3.5
Max.
8
1.0
3
5
2.1
Unit
Bits
%
µs
kΩ
mA
Table 36 Comparator characteristics
(VCC = 3.3 V ± 0.3V, VSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
Parameter
–
TCONV
Absolute accuracy
Conversion time
VIA
IIA
RLADDER
CMPREF
Analog input voltage
Analog input current
Ladder resistor
Internal reference voltage
External reference input voltage
Test conditions
Limits
Min.
Typ.
1LSB = VCC/16
at 8 MHz operating
at 4 MHz operating
0
20
40
Max.
1/2
3.5
7
VCC
5.0
50
29VCC/32
VCC/32
VCC
Unit
LSB
µs
µs
V
µA
kΩ
V
V
95
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Table 37 Timing requirements
(VCC = 3.3 V ± 0.3V, VSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
Limits
Parameter
Min.
16
125
50
50
20
5
5
200
80
80
Reset input “L” pulse width
Main clock input cycle time
Main clock input “H” pulse width
Typ.
Max.
Unit
tc(XIN)
ns
ns
ns
µs
µs
µs
ns
ns
ns
tW(RESET)
tC(XIN)
tWH(XIN)
tWL(XIN)
tC(XCIN)
tWH(XCIN)
tWL(XCIN)
tC(CNTR)
tWH(CNTR)
tWL(CNTR)
Main clock input “L” pulse width
Sub-clock input cycle time
Sub-clock input “H” pulse width
Sub-clock input “L” pulse width
CNTR0, CNTR1 input cycle time
CNTR0, CNTR1 input “H” pulse width
CNTR0, CNTR1 input “L” pulse width
tWH(INT)
INT0, INT1, INT20, INT30, INT40, INT21, INT31, INT41
input “H” pulse width
80
ns
tWL(INT)
INT0, INT1, INT20, INT30, INT40, INT21, INT31, INT41
input “L” pulse width
80
ns
tC(SCLK1)
tWH(SCLK1)
tWL(SCLK1)
tsu(RxD-SCLK1)
th(SCLK1-RxD)
Serial I/O clock input cycle time (Note)
Serial I/O clock input “H” pulse width (Note)
Serial I/O clock input “L” pulse width (Note)
Serial I/O input setup time
Serial I/O input hold time
800
370
370
220
100
ns
ns
ns
ns
ns
Note : When bit 6 of SIOCON is “1” (clock synchronous).
Divide this value by four when bit 6 of SIOCON is “0” (UART).
Table 38 Switching characteristics
(VCC = 3.3 V ± 0.3V, VSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
tWH (SCLK)
tWL (SCLK)
td (SCLK-TXD)
tV (SCLK-TXD)
tr (SCLK)
tf (SCLK)
tr (CMOS)
tf (CMOS)
Parameter
Serial I/O clock output “H” pulse width
Serial I/O clock output “L” pulse width
Serial I/O output delay time (Note 1)
Serial I/O output valid time (Note 1)
Serial I/O clock output rising time
Serial I/O clock output falling time
CMOS output rising time (Note 2)
CMOS output falling time (Note 2)
Notes 1: When the P45/TXD P-channel output disable bit (bit 4 of UARTCON) is “0”.
2: The XOUT pin is excluded.
96
Test
conditions
Limits
Min.
Typ.
tC(SCLK)/2–30
tC(SCLK)/2–30
Max.
140
Fig. 90
–30
10
10
30
30
30
30
Unit
ns
ns
ns
ns
ns
ns
ns
ns
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Measurement output pin
50pF
CMOS output
Fig. 83 Circuit for measuring output switching characteristics
97
MITSUBISHI MICROCOMPUTERS
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SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Timing diagram
tC(CNTR)
tWH(CNTR)
tWL(CNTR)
0.8VCC
CNTR0, CNTR1
0.2VCC
tWH(INT)
INT0, INT1, INT5
INT20, INT30, INT40
INT21, INT31, INT41
tWL(INT)
0.8VCC
0.2VCC
tW(RESET)
RESET
0.8VCC
0.2VCC
tC(XIN)
tWH(XIN)
tWL(XIN)
0.8VCC
XIN
0.2VCC
tC(XCIN)
tWH(XCIN)
tWL(XCIN)
0.8VCC
XCIN
0.2VCC
tC(SCLK)
tf
tr
tWL(SCLK)
SCLK
0.8VCC
0.2VCC
tsu(RxD-SCLK)
td(SCLK-TXD)
Fig. 84 Timing diagram
98
th(SCLK-RxD)
0.8VCC
0.2VCC
RXD
TXD
tWH(SCLK)
tv(SCLK-TXD)
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 39 Multi-master I2C-BUS bus line characteristics
Standard clock mode High-speed clock mode
Symbol
Parameter
Min.
Max.
Max.
Unit
tBUF
Bus free time
4.7
Min.
1.3
tHD;STA
Hold time for START condition
4.0
0.6
tLOW
Hold time for SCL clock = “0”
4.7
tR
Rising time of both SCL and SDA signals
tHD;DAT
Data hold time
tHIGH
Hold time for SCL clock = “1”
tF
Falling time of both SCL and SDA signals
tSU;DAT
Data setup time
250
100
ns
tSU;STA
Setup time for repeated START condition
4.7
0.6
µs
tSU;STO
Setup time for STOP condition
4.0
0.6
µs
µs
µs
µs
1.3
20+0.1Cb
300
ns
0
0
0.9
µs
4.0
0.6
1000
300
µs
20+0.1Cb
300
ns
Note: Cb = total capacitance of 1 bus line
SDA
tHD:STA
tBUF
tLOW
SCL
P
tR
tF
S
tHD:STA
Sr
tHD:DAT
tsu:STO
tHIGH
tsu:DAT
P
tsu:STA
S : START condition
Sr: RESTART condition
P : STOP condition
Fig. 85 Timing diagram of multi-master I2C-BUS
99
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Table 40 Timing requirements and switching characteristics
(VCC = 3.3 V ± 0.3V, VSS = 0 V, Ta = –20 to 85 °C, unless otherwise noted)
Symbol
tC(CLK)
tWH(CLK)
tWL(CLK)
tsu(D-C)
th(C-D)
Standard
Parameter
Min.
30
11
11
13
7
0
2
2
LCLK clock input cycle time
LCLK clock input “H” pulse width
LCLK clock input “L” pulse width
input set up time LAD3 to LAD0,
SERIRQ, CLKRUN, LFRAME
input hold time LAD3 to LAD0, CLKRUN, LFRAME
SERIRQ,
tV(C-D)
LAD3 to LAD0, SERIRQ, CLKRUN
valid delay time
toff(A-F)
LAD3 to LAD0,SERIRQ,CLKRUN
floating output delay time
Typ.
Max.
ns
ns
ns
ns
ns
15
ns
28
ns
Timing diagrams of LPC Bus Interface and Serial Interrupt Output
tC(CLK)
tWH(CLK)
LCLK
tWL(CLK)
VIH
VIL
tsu(D-C)
LAD[3:0]
SERIRQ, CLKRUN, LFRAME
(Input)
tv(C-D)
LAD[3:0]
SERIRQ, CLKRUN
(Active output)
toff(A-F)
LAD[3:0]
SERIRQ, CLKRUN
(Floating output )
Fig. 86 Timing diagram of LPC Interface and Serialized IRQ
100
Unit
th(C-D)
MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
PACKAGE OUTLINE
MMP
Plastic 80pin 12✕12mm body LQFP
Weight(g)
0.47
JEDEC Code
–
Lead Material
Cu Alloy
MD
HD
b2
D
80
ME
EIAJ Package Code
LQFP80-P-1212-0.5
e
80P6Q-A
61
1
l2
Recommended Mount Pad
60
A
A1
A2
b
c
D
E
e
HD
HE
L
L1
Lp
HE
E
Symbol
41
20
21
40
A
L1
F
M
y
L
Detail F
Lp
c
x
A1
b
A3
A2
e
A3
x
y
b2
I2
MD
ME
Dimension in Millimeters
Min
Nom
Max
–
–
1.7
0.1
0.2
0
–
–
1.4
0.13
0.18
0.28
0.105
0.125
0.175
11.9
12.0
12.1
11.9
12.0
12.1
0.5
–
–
13.8
14.0
14.2
13.8
14.0
14.2
0.3
0.5
0.7
1.0
–
–
0.45
0.6
0.75
–
0.25
–
–
–
0.08
0.1
–
–
0°
10°
–
0.225
–
–
0.9
–
–
12.4
–
–
–
–
12.4
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© 2002 MITSUBISHI ELECTRIC CORP.
New publication, effective June 2002.
Specifications subject to change without notice.
REVISION HISTORY
Rev.
3885 GROUP DATA SHEET
Date
Description
Summary
Page
1.0
06/04/02
First edition issued.
(1/X)
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