OKI MSM82C55A-2GS Cmos programmable peripheral interface Datasheet

E2O0020-27-X3
This version: Jan. 1998
MSM82C55A-2RS/GS/VJS
Previous version: Aug. 1996
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
¡ Semiconductor
CMOS PROGRAMMABLE PERIPHERAL INTERFACE
GENERAL DESCRIPTION
The MSM82C55A-2 is a programmable universal I/O interface device which operates as high
speed and on low power consumption due to 3m silicon gate CMOS technology. It is the best
fit as an I/O port in a system which employs the 8-bit parallel processing MSM80C85AH CPU.
This device has 24-bit I/O pins equivalent to three 8-bit I/O ports and all inputs/outputs are
TTL interface compatible.
FEATURES
• High speed and low power consumption due to 3m silicon gate CMOS technology
• 3 V to 6 V single power supply
• Full static operation
• Programmable 24-bit I/O ports
• Bidirectional bus operation (Port A)
• Bit set/reset function (Port C)
• TTL compatible
• Compatible with 8255A-5
• 40-pin Plastic DIP (DIP40-P-600-2.54): (Product name: MSM82C55A-2RS)
• 44-pin Plastic QFJ (QFJ44-P-S650-1.27): (Product name: MSM82C55A-2VJS)
• 44-pin Plastic QFP (QFP44-P-910-0.80-2K): (Product name: MSM82C55A-2GS-2K)
1/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
CIRCUIT CONFIGURATION
8
VCC
8
GND
Group A
Port A
(8)
8
PA0 - PA7
8
Group A
Control
8
D 0 - D7
Data
Bus
Buffer
Internal Bus Line
4
8
4
8
RD
WR
RESET
CS
Read/
Write
Control
Logic
Group A
Port C
(High Order
4 Bits)
Group B
Port C
(Low Order
4 Bits)
4
PC4 - PC7
4
PC0 - PC3
Group B
Control
8
Group B
Port B
(8)
8
PB0 - PB7
A0
A1
2/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
PIN CONFIGURATION (TOP VIEW)
40 pin Plastic DIP
1
2
3
4
RD 5
CS 6
GND 7
A1 8
A0 9
PC7 10
PC6 11
PC5 12
PC4 13
PC0 14
PC1 15
PC2 16
PC3 17
PB0 18
PB1 19
PB2 20
PA3
PA2
PA1
PA0
34 WR
24
23
22
21
PB6
PB5
PB4
PB3
D4
D5
D6
D7
VCC
PB7
D0
D1
D2.
D3
D4
D5
D6
D7
VCC
PB7
40 WR
41 PA7
43 PA5
42 PA6
1 NC
44 PA4
2 PA3
6 RD
5 PA0
39
38
37
36
35
34
33
32
31
30
29
RESET
D0
D1
D2.
D3
NC
D4
D5
D6
D7
VCC
PB7 28
PB5 26
PB6 27
PB3 24
PB4 25
PB2 22
NC 23
7
8
9
10
11
12
13
14
15
16
17
PB0 20
PB1 21
CS
GND
A1
A0
PC7
NC
PC6
PC5
PC4
PC0
PC1
4 PA1
3 PA2
44 pin Plastic QFJ
PB6 21
NC 22
PB3 18
PB4 19
PB5 20
VCC
17
PB1 15
PB2 16
PA4
PA5
PA6
PA7
WR
RESET
D0
D1
D2
D3
RESET
PC2 18
PC3 19
35 PA7
37 PA5
36 PA6
38 PA4
39 VCC
40 PA3
33
32
31
30
29
28
27
26
25
24
23
1
2
3
4
5
6
7
8
9
10
11
NC 12
PC3 13
PB0 14
CS
GND
A1
A0
PC7
PC6
PC5
PC4
PC0
PC1
PC2
42 PA1
41 PA2
44 RD
43 PA0
44 pin Plastic QFP
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
3/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
ABSOLUTE MAXIMUM RATINGS
Parameter
Rating
Conditions
Symbol
Unit
MSM82C55A-2RS MSM82C55A-2GS MSM82C55A-2vJS
Supply Voltage
VCC
Input Voltage
VIN
Output Voltage
Ta = 25°C
with respect
to GND
VOUT
TSTG
Storage Temperature
Power Dissipation
—
PD
Ta = 25°C
–0.5 to +7
V
–0.5 to VCC +0.5
V
–0.5 to VCC +0.5
V
–55 to +150
°C
1.0
0.7
1.0
W
OPERATING RANGE
Symbol
Range
Unit
Supply Voltage
Parameter
VCC
3 to 6
V
Operating Temperature
Top
–40 to 85
°C
RECOMMENDED OPERATING RANGE
Parameter
Symbol
Min.
Typ.
Max.
Unit
Supply Voltage
VCC
4.5
5
5.5
V
Operating Temperature
Top
–40
+25
+85
°C
"L" Input Voltage
VIL
–0.3
—
+0.8
V
"H" Input Voltage
VIH
2.2
—
VCC + 0.3
V
DC CHARACTERISTICS
Parameter
Symbol
"L" Output Voltage
VOL
"H" Output Voltage
VOH
Conditions
MSM82C55A-2
Unit
Min.
Typ.
Max.
IOL = 2.5 mA
—
—
0.4
V
IOH = –40 mA
4.2
—
—
V
IOH = –2.5 mA
3.7
—
—
V
Input Leak Current
ILI
0 £ VIN £ VCC
Output Leak Current
ILO
0 £ VOUT £ VCC
Supply Current
(Standby)
ICCS
CS ≥ VCC –0.2 V
VIH ≥ VCC –0.2 V
VIL £ 0.2 V
Average Supply
Current (Active)
ICC
I/O Wire Cycle
82C55A-2
...8 MHzCPU Timing
VCC = 4.5 V to 5.5 V
Ta = –40°C to +85°C
(CL = 0 pF)
–1
—
1
mA
–10
—
10
mA
—
0.1
10
mA
—
—
8
mA
4/26
¡ Semiconductor
AC CHARACTERISTICS
Parameter
Setup Time of Address to the Falling Edge of RD
MSM82C55A-2RS/GS/VJS
(VCC = 4.5 V to 5.5 V, Ta = –40 to +85°C)
MSM82C55A-2
Symbol
Unit Remarks
Min.
Max.
tAR
20
—
ns
Hold Time of Address to the Rising Edge of RD
tRA
0
—
ns
RD Pulse Width
tRR
100
—
ns
Delay Time from the Falling Edge of RD to the Output of
Defined Data
tRD
—
120
ns
Delay Time from the Rising Edge of RD to the Floating of
Data Bus
tDF
10
75
ns
Time from the Rising Edge of RD or WR to the Next Falling
Edge of RD or WR
tRV
200
—
ns
Setup Time of Address before the Falling Edge of WR
tAW
0
—
ns
Hold Time of Address after the Rising Edge of WR
tWA
20
—
ns
WR Pulse Width
tWW
150
—
ns
Setup Time of Bus Data before the Rising Edge of WR
tDW
50
—
ns
Hold Time of Bus Data after the Rising Edge of WR
tWD
30
—
ns
Delay Time from the rising Edge of WR to the Output of
Defined Data
tWB
—
200
ns
Setup Time of Port Data before the Falling Edge of RD
tIR
20
—
ns
Hold Time of Port Data after the Rising Edge of RD
tHR
10
—
ns
ACK Pulse Width
tAK
100
—
ns
STB Pulse Width
tST
100
—
ns
Setup Time of Port Data before the rising Edge of STB
tPS
20
—
ns
Hold Time of Port Bus Data after the rising Edge of STB
tPH
50
—
ns
Delay Time from the Falling Edge of ACK to the Output of
Defined Data
tAD
—
150
ns
Delay Time from the Rising Edge of ACK to the Floating of
Port (Port A in Mode 2)
tKD
20
250
ns
Delay Time from the Rising Edge of WR to the Falling Edge of
OBF
tWOB
—
150
ns
Delay Time from the Falling Edge of ACK to the Rising Edge of
OBF
tAOB
—
150
ns
Delay Time from the Falling Edge of STB to the Rising Edge of
IBF
tSIB
—
150
ns
Delay Time from the Rising Edge of RD to the Falling Edge of
IBF
tRIB
—
150
ns
Delay Time from the the Falling Edge of RD to the Falling Edge
of INTR
tRIT
—
200
ns
Delay Time from the Rising Edge of STB to the Rising Edge of
INTR
tSIT
—
150
ns
Delay Time from the Rising Edge of ACK to the Rising Edge of
INTR
tAIT
—
150
ns
Delay Time from the Falling Edge of WR to the Falling Edge of
INTR
tWIT
—
250
ns
Load
150 pF
Note: Timing measured at VL = 0.8 V and VH = 2.2 V for both inputs and outputs.
5/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
TIMING DIAGRAM
Basic Input Operation (Mode 0)
tRR
RD
tIR
tHR
Port Input
tAR
tRA
CS, A1, A0
D7 - D0
tRD
tDF
Basic Output Operation (Mode 0)
tWW
WR
tDW
tWD
D 7 - D0
tAW
tWA
CS, A1, A0
Port Output
tWB
Strobe Input Operation (Mode 1)
tST
STB
tSIB
IBF
tSIT
tRIB
INTR
tRIT
RD
tPH
Port Input
tPS
6/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
Strobe Output Operation (Mode 1)
WR
tAOB
OBF
tWOB
INTR
tWIT
ACK
tAIT
tAK
Port Output
tWB
Bidirectional Bus Operation (Mode 2)
WR
tAOB
OBF
tWOB
INTR
tAK
ACK
STB
tST
tSIB
IBF
tAD
tPS
tKD
Port A
RD
tPH
tRIB
7/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
OUTPUT CHARACTERISTICS (REFERENCE VALUE)
1
Output "H" Voltage (VOH) vs. Output Current (IOH)
Output "H" Voltage VOH (V)
5
Ta = –40 to + 85°C
VCC = 5.0 V
4
3
2
1
0
0
–1
–2
–3
–4
–5
Output Current IOH (mA)
Output "L" Voltage (VOL) vs. Output Current (IOL)
5
Output "L" Voltage VOL (V)
2
4
3
2
VCC = 5.0 V
Ta = –40 to +85°C
1
0
0
1
2
3
4
5
Output Current IOL (mA)
Note: The direction of flowing into the device is taken as positive for the output current.
8/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
PIN DESCRIPTION
Pin No.
D 7 - D0
Item
Bidirectional
Data Bus
Input/Output
Function
Input and
Output
These are three-state 8-bit bidirectional buses used to write and
read data upon receipt of the WR and RD signals from CPU and also
used when control words and bit set/reset data are transferred from
CPU to MSM82C55A-2.
This signal is used to reset the control register and all internal
registers when it is in high level. At this time, ports are all made into
the input mode (high impedance status).
all port latches are cleared to 0.
and all ports groups are set to mode 0.
RESET
Reset Input
Input
CS
Chip Select
Input
Input
RD
Read Input
Input
When RD is in low level, data is transferred from MSM82C55A-2 to
CPU.
WR
Write Input
Input
When WR is in low level, data or control words are transferred from
CPU to MSM82C55A-2.
A0 , A 1
Port Select Input
(Address)
Input
By combination of A0 and A1, either one is selected from among
port A, port B, port C, and control register. These pins are usually
connected to low order 2 bits of the address bus.
PA7 - PA0
Port A
Input and
Output
These are universal 8-bit I/O ports. The direction of inputs/ outputs
can be determined by writing a control word. Especially, port A can
be used as a bidirectional port when it is set to mode 2.
PB7 - PB0
Port B
Input and
Output
These are universal 8-bit I/O ports. The direction of inputs/outputs
ports can be determined by writing a control word.
These are universal 8-bit I/O ports. The direction of inputs/outputs
can be determined by writing a control word as 2 ports with 4 bits
each. When port A or port B is used in mode 1 or mode 2 (port A
only), they become control pins. Especially, when port C is used as
an output port, each bit can set/reset independently.
When the CS is in low level, data transmission is enabled with CPU.
When it is in high level, the data bus is made into the high impedance
status where no write nor read operation is performed. Internal
registers hold their previous status, however.
PC7 - PC0
Port C
Input and
Output
VCC
–
–
+5V power supply.
GND
–
–
GND
9/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
BASIC FUNCTIONAL DESCRIPTION
Group A and Group B
When setting a mode to a port having 24 bits, set it by dividing it into two groups of 12 bits each.
Group A: Port A (8 bits) and high order 4 bits of port C (PC7~PC4)
Group B: Port B (8 bits) and low order 4 bits of port C (PC3~PC0)
Mode 0, 1, 2
There are 3 types of modes to be set by grouping as follows:
Mode 0: Basic input operation/output operation (Available for both groups A and B)
Mode 1: Strobe input operation/output operation (Available for both groups A and B)
Mode 2: Bidirectional bus operation (Available for group A only)
When used in mode 1 or mode 2, however, port C has bits to be defined as ports for control signal
for operation ports (port A for group A and port B for group B) of their respective groups.
Port A, B, C
The internal structure of 3 ports is as follows:
Port A: One 8-bit data output latch/buffer and one 8-bit data input latch
Port B: One 8-bit data input/output latch/buffer and one 8-bit data input buffer
Port C: One 8-bit data output latch/buffer and one 8-bit data input buffer (no latch for input)
Single bit set/reset function for port C
When port C is defined as an output port, it is possible to set (to turn to high level) or reset (to
turn to low level) any one of 8 bits individually without affecting other bits.
10/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
OPERATIONAL DESCRIPTION
Control Logic
Operations by addresses and control signals, e.g., read and write, etc. are as shown in the table
below:
Operaiton
Input
Output
Control
Others
RD
A0
CS
0
0
0
1
0
Port A Æ Data Bus
0
1
1
0
0
0
1
1
0
0
Port B Æ Data Bus
0
0
0
0
1
Data Bus Æ Port A
A1
WR
Operation
Port C Æ Data Bus
0
1
0
0
1
Data Bus Æ Port B
1
0
0
0
1
1
1
0
0
1
Data Bus Æ Port C
Data Bus Æ Control Register
1
1
0
1
0
Illegal Condition
¥
¥
1
¥
¥
Data bus is in the high impedance status.
Setting of Control Word
The control register is composed of 7-bit latch circuit and 1-bit flag as shown below.
Group A Control Bits
D7
D6
D5
D4
Group B Control Bits
D3
D2
D1
D0
Definition of input/
output of low order
4 bits of port C.
Definition of input/
output of 8 bits of
port B.
Mode definition of
group B.
Definition of input/
output of high order
4 bits of port C.
Definition of input/
output of 8 bits of
port A.
0 = Output
1 = Input
0 = Output
1 = Input
0 = Mode 0
1 = Mode 1
0 = Output
1 = Input
0 = Output
1 = Input
Mode definition of group A.
Control word Identification flag
Be sure to set 1 for the control word
to define a mode and input/output.
When set to 0, it becomes
the control word for bit set/
reset.
D6 D5
0 0
0 1
1 ¥
Mode
Mode 0
Mode 1
Mode 2
11/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
Precaution for Mode Selection
The output registers for ports A and C are cleared to f each time data is written in the command
register and the mode is changed, but the port B state is undefined.
Bit Set/Reset Function
When port C is defined as output port, it is possible to set (set output to 1) or reset (set output
to 0) any one of 8 bits without affecting other bits as shown below.
D7
D6
D5
D4
D3
D2
D1
D0
Definition of set/reset
for a desired bit.
0 = Reset
1 = Set
Definition of bit wanted
to be set or reset.
Dont's Care
Control word Identification flag
Be sure to set to 0 for bit set/reset
When set to 1, it becomes the control
word to define a mode and input/output.
Port C
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
D3 D2 D1
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Interrupt Control Function
When the MSM82C55A-2 is used in mode 1 or mode 2, the interrupt signal for the CPU is
provided. The interrupt request signal is output from port C. When the internal flip-flop INTE
is set beforehand at this time, the desired interrupt request signal is output. When it is reset
beforehand, however, the interrupt request signal is not output. The set/reset of the internal
flip-flop is made by the bit set/reset operation for port C virtually.
Bit set Æ INTE is set Æ Interrupt allowed
Bit reset Æ INTE is reset Æ Interrupt inhibited
Operational Description by Mode
1. Mode 0 (Basic input/output operation)
Mode 0 makes the MSM82C55A-2 operate as a basic input port or output port. No control
signals such as interrupt request, etc. are required in this mode. All 24 bits can be used as
two-8-bit ports and two 4-bit ports. Sixteen combinations are then possible for inputs/
outputs. The inputs are not latched, but the outputs are.
12/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
Control Word
Group A
Type
D7 D 6 D 5 D 4 D 3 D 2 D 1 D 0
Group B
Port A
High Order 4 Bits
of Port C
Port B
Low Order 4 Bits
of Port C
Output
1
1
0
0
0
0
0
0
0
Output
Output
Output
2
1
0
0
0
0
0
0
1
Output
Output
Output
Input
3
1
0
0
0
0
0
1
0
Output
Output
Input
Output
4
1
0
0
0
0
0
1
1
Output
Output
Input
Input
5
1
0
0
0
1
0
0
0
Output
Input
Output
Output
6
1
0
0
0
1
0
0
1
Output
Input
Output
Input
7
1
0
0
0
1
0
1
0
Output
Input
Input
Ouput
8
1
0
0
0
1
0
1
1
Output
Input
Input
Input
9
1
0
0
1
0
0
0
0
Input
Output
Output
Output
10
1
0
0
1
0
0
0
1
Input
Output
Output
Input
11
1
0
0
1
0
0
1
0
Input
Output
Input
Output
12
1
0
0
1
0
0
1
1
Input
Output
Input
Input
13
1
0
0
1
1
0
0
0
Input
Input
Output
Output
14
1
0
0
1
1
0
0
1
Input
Input
Output
Input
15
1
0
0
1
1
0
1
0
Input
Input
Input
Output
16
1
0
0
1
1
0
1
1
Input
Input
Input
Input
Notes: When used in mode 0 for both groups A and B
2. Mode 1 (Strobe input/output operation)
In mode 1, the strobe, interrupt and other control signals are used when input/output
operations are made from a specified port. This mode is available for both groups A and
B. In group A at this time, port A is used as the data line and port C as the control signal.
Following is a description of the input operation in mode 1.
STB (Strobe input)
When this signal is low level, the data output from terminal to port is fetched into the
internal latch of the port. This can be made independent from the CPU, and the data is not
output to the data bus until the RD signal arrives from the CPU.
IBF (Input buffer full flag output)
This is the response signal for the STB. This signal when turned to high level indicates that
data is fetched into the input latch. This signal turns to high level at the falling edge of STB
and to low level at the rising edge of RD.
INTR (Interrupt request output)
This is the interrupt request signal for the CPU of the data fetched into the input latch. It
is indicated by high level only when the internal INTE flip-flop is set. This signal turns to
high level at the rising edge of the STB (IBF = 1 at this time) and low level at the falling edge
of the RD when the INTE is set.
INTE A of group A is set when the bit for PC4 is set, while INTE B of group B is set when the
bit for PC2 is set.
Following is a description of the output operation of mode 1.
13/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
OBF (Output buffer full flag output)
This signal when turned to low level indicates that data is written to the specified port upon
receipt of the WR signal from the CPU. This signal turns to low level at the rising edge of
the WR and high level at the falling edge of the ACK.
ACK (Acknowledge input)
This signal when turned to low level indicates that the terminal has received data.
INTR (Interrupt request output)
This is the signal used to interrupt the CPU when a terminal receives data from the CPU via
the MSM82C55A-5. It indicates the occurrence of the interrupt in high level only when the
internal INTE flip-flop is set. This signal turns to high level at the rising edge of the ACK
(OBF = 1 at this time) and low level at the falling edge of WR when the INTE B is set.
INTE A of group A is set when the bit for PC6 is set, while INTE B of group B is set when the
bit for PC2 is set.
Mode 1 Input
(Group A)
(Group B)
8
INTEA
8
-
PB7
-
PA7
INTEB
PA0
PB0
PC4
STBA
PC2
STBB
PC5
IBFA
PC1
IBFB
PC3
INTRA
PC0
INTRB
RD
RD
Note: Although belonging to group B, PC3 operates as the control signal of
group A functionally.
Mode 1 Output
(Group A)
(Group B)
8
INTEA
8
-
PB7
-
PA7
INTEB
PA0
PB0
PC7
OBFA
PC1
OBFB
PC6
ACKA
PC2
ACKB
PC0
INTRB
WR
WR
PC3
INTRA
14/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
Port C Function Allocation in Mode 1
Combination of
Input/Output
Port C
Group A: Input
Group B: Input
PC0
Group A: Input Group A: Output
Group B: Output Group B: Input
INTRB
INTRB
Group A: Output
Group B: Output
INTRB
INTRB
OBFB
PC1
IBFB
OBFB
IBFB
PC2
STBB
ACKB
STBB
ACKB
PC3
INTRA
INTRA
INTRA
INTRA
PC4
STBA
STBA
I/O
I/O
PC5
IBFA
IBFA
I/O
I/O
PC6
I/O
I/O
ACKA
ACKA
PC7
I/O
I/O
OBFA
OBFA
Note: I/O is a bit not used as the control signal, but it is available as a port of mode 0.
Examples of the relation between the control words and pins when used in mode 1 are
shown below:
(a) When group A is mode 1 output and group B is mode 1 input.
Control Word
D7
D6
D5
D4
D3
D2
D1
D0
1
0
1
0
1/0
1
1
¥
Selection of I/O
of PC4 and PC5
when not defined
as a control pin.
1 = Input
0 = Output
As all of PC0 - PC3 bits
become a control pin
in this case, this bit is
"Don't Care".
8
WR
RD
PA7 - PA0
PC7
PC6
PC3
PC4, PC5 2
PB7 - PB0
PC2
PC1
PC0
OBFA
ACKA
INTRA
I/O
8
Group A: Mode 1 Output
Group B: Mode 1 Input
STBB
IBFB
INTRB
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
(b) When group A is mode 1 input and group B is mode 1 output.
D7
D6
D5
D4
D3
D2
D1
D0
1
0
1
1
1/0
1
0
¥
Selection of I/O of PC6 and PC7
when not defined as a control pin.
1 = Input
0 = Output
RD
WR
PA7 - PA0
PC4
PC5
PC3
PC6, PC7
PB7 - PB0
PC1
PC2
PC0
8
2
STBA
IBFA
INTRA
I/O
8
Group A: Mode 1 Input
Group B: Mode 1 Output
OBFB
ACKB
INTRB
3. Mode 2 (Strobe bidirectional bus I/O operation)
In mode 2, it is possible to transfer data in 2 directions through a single 8-bit port. This
operation is akin to a combination between input and output operations. Port C waits for
the control signal in this case, too. Mode 2 is available only for group A, however.
Next, a description is made on mode 2.
OBF (Output buffer full flag output)
This signal when turned to low level indicates that data has been written to the internal
output latch upon receipt of the WR signal from the CPU. At this time, port A is still in the
high impedance status and the data is not yet output to the outside. This signal turns to low
level at the rising edge of the WR and high level at the falling edge of the ACK.
ACK (Acknowledge input)
When a low level signal is input to this pin, the high impedance status of port A is cleared,
the buffer is enabled, and the data written to the internal output latch is output to port A.
When the input returns to high level, port A is made into the high impedance status.
STB (Strobe input)
When this signal turns to low level, the data output to the port from the pin is fetched into
the internal input latch. The data is output to the data bus upon receipt of the RD signal from
the CPU, but it remains in the high impedance status until then.
IBF (Input buffer full flag output)
This signal when turned to high level indicates that data from the pin has been fetched into
the input latch. This signal turns to high level at the falling edge of the STB and low level
at the rising edge of the RD.
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
INTR (Interrupt request output)
This signal is used to interrupt the CPU and its operation in the same as in mode 1. There
are two INTE flip-flops internally available for input and output to select either interrupt
of input or output operation. The INTE1 is used to control the interrupt request for output
operation and it can be reset by the bit set for PC6. INTE2 is used to control the interrupt
request for the input operation and it can be set by the bit set for PC4.
Mode 2 I/O Operation
PC3
-
PA7
INTRA
8
PA0
WR
RD
PC7
OBFA
INTE1
PC6
ACKA
INTE2
PC4
STBA
PC5
IBFA
Port C Function Allocation in Mode 2
Port C
Function
PC0
PC1
Confirmed to the Group B Mode
PC2
PC3
PC4
INTRA
STBA
PC5
IBFA
PC6
ACKA
PC7
OBFA
Following is an example of the relation between the control word and the pin when used in
mode 2.
When input in mode 2 for group A and in mode 1 for group B.
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
D7
D6
D5
D4
D3
D2
D1
D0
1
1
¥
¥
¥
1
1
¥
As all of 8 bits of port C become
control pins in this case, D3 and
D0 bits are treated as "Don't Care".
No I/O specification is required for mode 2,
since it is a bidirectional operation.
This bit is therefore treated as "Don't Care".
When group A is set to mode 2, this bit is treated
as "Don't Care".
PC3
PA7 - PA0
PC7
PC6
PC4
PC5
RD
WR
PB7 - PB0
PC2
PC1
PC0
INTRA
8
OBFA
ACKA
STBA
IBFA
Group A: Mode 2
Group B: Mode 1 Input
8
STBB
IBFB
INTRB
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
4. When Group A is Different in Mode from Group B
Group A and group B can be used by setting them in different modes each other at the same
time. When either group is set to mode 1 or mode 2, it is possible to set the one not defined
as a control pin in port C to both input and output as port which operates in mode 0 at the
3rd and 0th bits of the control word.
(Mode combinations that define no control bit at port C)
PC7
PC6
PC5
Port C
PC4
PC3
Mode 0
I/O
I/O
IBFA
STBA
INTRA
I/O
I/O
I/O
Mode 0
Output
Mode 0
OBFA
ACKA
I/O
I/O
INTRA
I/O
I/O
I/O
3
Mode 0
Mode 1
Input
I/O
I/O
I/O
I/O
I/O
STBB
IBFB
INTRB
4
Mode 0
Mode 1
Output
I/O
I/O
I/O
I/O
I/O
ACKB
OBFB
INTRB
5
Mode 1
Input
Mode 1
Input
I/O
I/O
IBFA
STBA
INTRA
STBB
IBFB
INTRB
6
Mode 1
Input
Mode 1
Output
I/O
I/O
IBFA
STBA
INTRA
ACKB
OBFB
INTRB
7
Mode 1
Output
Mode 1
Input
OBFA
ACKA
I/O
I/O
INTRA
STBB
IBFB
INTRB
8
Mode 1
Output
OBFA
ACKA
I/O
I/O
INTRA
ACKB
OBFB
INTRB
9
Mode 2
Mode 1
Output
Mode 0
OBFA
ACKA
IBFA
STBA
INTRA
I/O
I/O
I/O
Group A
Group B
1
Mode 1
input
2
Controlled at the 3rd bit (D3) of
the Control Word
PC2
PC1
PC0
Controlled at the 0th bit (D0) of
the Control Word
When the I/O bit is set to input in this case, it is possible to access data by the normal port
C read operation.
When set to output, PC7-PC4 bits can be accessed by the bit set/reset function only.
Meanwhile, 3 bits from PC2 to PC0 can be accessed by normal write operation.
The bit set/reset function can be used for all of PC3-PC0 bits. Note that the status of port C
varies according to the combination of modes like this.
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
5. Port C Status Read
When port C is used for the control signal, that is, in either mode 1 or mode 2, each control
signal and bus status signal can be read out by reading the content of port C.
The status read out is as follows:
D7
D6
Status Read on the Data Bus
D5
D4
D3
D2
Mode 0
I/O
I/O
IBFA
INTEA
INTRA
Mode 1
Output
Mode 0
OBFA
INTEA
I/O
I/O
3
Mode 0
Mode 1
Input
I/O
I/O
I/O
4
Mode 0
Mode 1
Output
I/O
I/O
5
Mode 1
Input
Mode 1
Input
I/O
6
Mode 1
Input
Mode 1
Output
7
Mode 1
Output
Mode 1
Input
8
Mode 1
Output
9
Mode 2
10
11
Group A
Group B
1
Mode 1
Input
2
D1
D0
I/O
I/O
I/O
INTRA
I/O
I/O
I/O
I/O
I/O
INTEB
IBFB
INTRB
I/O
I/O
I/O
INTEB
OBFB
INTRB
I/O
IBFA
INTEA
INTRA
INTEB
IBFB
INTRB
I/O
I/O
IBFA
INTEA
INTRA
INTEB
OBFB
INTRB
OBFA
INTEA
I/O
I/O
INTRA
INTEB
IBFB
INTRB
Mode 1
Output
Mode 0
OBFA
INTEA
I/O
I/O
INTRA
INTEB
OBFB
INTRB
OBFA
INTE1
IBFA
INTE2
INTRA
I/O
I/O
I/O
Mode 2
Mode 1
Input
OBFA
INTE1
IBFA
INTE2
INTRA
INTEB
IBFB
INTRB
Mode 2
Mode 1
Output
OBFA
INTE1
IBFA
INTE2
INTRA
INTEB
OBFB
INTRB
6. Reset of MSM82C55A-2
Be sure to keep the RESET signal at power ON in the high level at least for 50 ms.
Subsequently, it becomes the input mode at a high level pulse above 500 ns.
Note: Comparison of MSM82C55A-5 and MSM82C55A-2
MSM82C55A-5
After a write command is executed to the command register, the internal latch is cleared in
PORTA PORTC. For instance, 00H is output at the beginning of a write command when
the output port is assigned. However, if PORTB is not cleared at this time, PORTB is
unstable. In other words, PORTB only outputs ineffective data (unstable value according
to the device) during the period from after a write command is executed till the first data
is written to PORTB.
MSM82C55A-2
After a write command is executed to the command register, the internal latch is cleared in
All Ports (PORTA, PORTB, PORTC). 00H is output at the beginning of a write command
when the output port is assigned.
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
NOTICE ON REPLACING LOW-SPEED DEVICES WITH HIGH-SPEED DEVICES
The conventional low speed devices are replaced by high-speed devices as shown below.
When you want to replace your low speed devices with high-speed devices, read the replacement
notice given on the next pages.
High-speed device (New)
Remarks
M80C85AH
Low-speed device (Old)
M80C85A/M80C85A-2
M80C86A-10
M80C86A/M80C86A-2
16bit MPU
M80C88A-10
M80C88A/M80C88A-2
8bit MPU
M82C84A-2
M82C84A/M82C84A-5
Clock generator
M81C55-5
M82C37B-5
M81C55
M82C37A/M82C37A-5
RAM.I/O, timer
DMA controller
M82C51A-2
M82C51A
USART
M82C53-2
M82C55A-2
M82C53-5
M82C55A-5
Timer
PPI
8bit MPU
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
Differences between MSM82C55A-5 and MSM82C55A-2
1) Manufacturing Process
These devices use a 3 m Si-Gate CMOS process technology.
The MSM82C55A-2 is about 7% smaller in chip size than the MSM82C55A-5 as the MSM82C55A2 changed its output characteristics.
2) Function
Item
Internal latch during writing into
the command register
MSM82C55A-5
Only ports A and C are cleared.
Port B is not cleared.
MSM82C55A-2
All ports are cleared.
The above function has been improved to remove bugs and other logics are not different between
the two devices.
3) Electrical Characteristics
3-1) DC Characteristics
Parameter
Symbol
MSM82C55A-5
MSM82C55A-2
''L'' Output Voltage
VOL
0.45 V
(IOL = +2.5 mA)
0.40 V
(IOL = +2.5 mA)
''H'' Output Voltage
VOH
2.4 V
(IOH = -400 mA)
3.7 V
(IOH = -2.5 mA)
Average Operating Current
ICC
5 mA maximum
(I/O Cycle = 1 ms)
8 mA maximum
(I/O Cycle = 375 ns)
As shown above, the DC characteristics of the MSM82C55A-2 satisfies the DC characteristics of the
MSM82C55A-5.
3-2) AC Characteristics
Parameter
Symbol
MSM82C55A-5
MSM82C55A-2
Address Hold Time for RD Rising
tRA
20 ns minimum
0 ns minimum
RD Pulse Width
tRR
300 ns minimum
100 ns minimum
Difined Data Output Delay Time
From RD Falling
tRD
200 ns maximum
120 ns maximum
Data Floating Delay Time From RD Rising
tRF
100 ns maximum
75 ns maximum
RD/WR Recovery Time
tRV
850 ns minimum
200 ns minimum
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¡ Semiconductor
Parameter
MSM82C55A-2RS/GS/VJS
Symbol
MSM82C55A-5
MSM82C55A-2
Address Hold Time for WR Rising
tWA
30 ns minimum
20 ns minimum
WR Pulse Width
tWW
300 ns minimum
150 ns minimum
Data Setup Time for WR Rising
tDW
1000 ns minimum
50 ns minimum
Data Hold Time for WR Rising
tWD
40 ns minimum
30 ns minimum
Defined Data Output Time
From WR Rising
tWB
350 ns maximum
200 ns maximum
Port Data Hold Time for RD Rising
tHR
20 ns minimum
10 ns minimum
ACK Pulse Width
tAK
300 ns minimum
100 ns minimum
STB Pulse Width
tST
300 ns minimum
100 ns minimum
Port Data Hold Time for STB Falling
tPH
180 ns minimum
50 ns minimum
ACK Falling to Defined Data Output
tAD
300 ns maximum
150 ns maximum
WR Falling to OBF Falling Delay Time
tWOB
650 ns maximum
150 ns maximum
ACK Falling to OBF Rising Delay Time
tAOB
350 ns maximum
150 ns maximum
STB Falling to IBF Rising Delay Time
tSIB
300 ns maximum
150 ns maximum
RD Rising to IBF Falling Delay Time
tRIB
300 ns maximum
150 ns maximum
RD Falling to INTR Falling Delay Time
tRIT
400 ns maximum
200 ns maximum
STB Rising to INTR Rising Delay Time
tSIT
300 ns maximum
150 ns maximum
ACK Rising to INTR Rising Delay Time
tAIT
350 ns maximum
150 ns maximum
WR Falling to INTR Falling Delay Time
tWIT
850 ns minimum
250 ns maximum
As shown above, the MSM82C55A-2 satisfies the characteristics of the MSM82C55A-5.
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
PACKAGE DIMENSIONS
(Unit : mm)
DIP40-P-600-2.54
Package material
Lead frame material
Pin treatment
Solder plate thickness
Package weight (g)
Epoxy resin
42 alloy
Solder plating
5 mm or more
6.10 TYP.
Notes for Mounting the Surface Mount Type Package
The SOP, QFP, TSOP, SOJ, QFJ (PLCC), SHP and BGA are surface mount type packages, which
are very susceptible to heat in reflow mounting and humidity absorbed in storage.
Therefore, before you perform reflow mounting, contact Oki’s responsible sales person for the
product name, package name, pin number, package code and desired mounting conditions
(reflow method, temperature and times).
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¡ Semiconductor
MSM82C55A-2RS/GS/VJS
(Unit : mm)
QFJ44-P-S650-1.27
Mirror finish
Package material
Lead frame material
Pin treatment
Solder plate thickness
Package weight (g)
Epoxy resin
Cu alloy
Solder plating
5 mm or more
2.00 TYP.
Notes for Mounting the Surface Mount Type Package
The SOP, QFP, TSOP, SOJ, QFJ (PLCC), SHP and BGA are surface mount type packages, which
are very susceptible to heat in reflow mounting and humidity absorbed in storage.
Therefore, before you perform reflow mounting, contact Oki’s responsible sales person for the
product name, package name, pin number, package code and desired mounting conditions
(reflow method, temperature and times).
25/26
¡ Semiconductor
MSM82C55A-2RS/GS/VJS
(Unit : mm)
QFP44-P-910-0.80-2K
Mirror finish
Package material
Lead frame material
Pin treatment
Solder plate thickness
Epoxy resin
42 alloy
Solder plating
5 mm or more
Package weight (g)
0.41 TYP.
Notes for Mounting the Surface Mount Type Package
The SOP, QFP, TSOP, SOJ, QFJ (PLCC), SHP and BGA are surface mount type packages, which
are very susceptible to heat in reflow mounting and humidity absorbed in storage.
Therefore, before you perform reflow mounting, contact Oki’s responsible sales person for the
product name, package name, pin number, package code and desired mounting conditions
(reflow method, temperature and times).
26/26