MITSUBISHI MICROCOMPUTERS
4280 Group
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER for INFRARED REMOTE CONTROL TRANSMITTERS
PORT BLOCK DIAGRAMS
Register Y
SD instruction
RD instruction
CLD instruction
Decoder
(Note 1)
S
R
Q
Ports D
0
–D
6
Register Y
SD instruction
RD instruction
Decoder
(Note 1)
S Q
R
CLD instruction
Pull-down
transistor
PU0
2
Port D
7
(Note 4)
Skip decision (SZD instruction)
Key-on wakeup input
Register A
A
0
OEA
instruction
A
0
Key-on wakeup input
PU0
0
Register A
A
1
A
1
OEA
instruction
D Q
T
IAE instruction
Pull-down
transistor
D Q
T
IAE instruction
(Note 1)
Port E
0
(Note 4)
(Note 1)
Port E
1
(Note 4)
Key-on wakeup input
PU0
1
IAE instruction
Pull-down
transistor
Register A
A
2
Key-on wakeup input
Port E
2
(Note 4)
(Note 1)
Pull-down
transistor
Register A
A
i
(Note 2)
A
i
Key-on wakeup input
TCA instruction
Register A
A
j
(Note 3)
Register C
OGA
instruction
D Q
T
IAG instruction
Pull-down
transistor
(Note 1)
Ports G
0
–G
3
(Note 4)
Register A
A
j
(Note 3)
TAC instruction
To timer 1
CARRY
(Note 1)
Carrier wave
output circuit
Register A
A
3
OCRA instruction
Timer 1 underflow signal
V1
2
Port CARR
D Q
T R
TCA
instruction
D Q
T R
V1
0
Carrier wave
output control
signal
Notes 1:
This symbol represents a parasitic diode.
2: i represents bits 0 to 3.
3: j represents bits 0 to 2.
4: Applied voltage must be less than V
DD
.
MITSUBISHI
ELECTRIC
5
MITSUBISHI [ MITSUBISHI ELECTRIC SEMICONDUCTOR ]
