455A Datasheet, PDF (9/148 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

455A Group
PORT BLOCK DIAGRAM
Register Y
Decoder
Skip decision
SZD instruction
SD instruction
RD instruction
CLD
instruction
Note3 _FR1i
S
RQ
Key-on wakeup
input
Edge detection
circuit
Note4
K3j
Note1
D0 D3 Note2
Note1
Note4
PU3j
Pull-up
transistor
Register Y
Decoder
Skip decision
SZD instruction
SD instruction
RD instruction
CLD
instruction
FR20
S
RQ
K32
Key-on wakeup
Edge detection
input
circuit
Note1
D4 Note2)
Note1
PU32
Pull-up
transistor
K32
Key-on wakeup
Edge detection
input
circuit
Register Y
Decoder
Skip decision
SZD instruction
SD instruction
RD instruction
CLD
instruction
FR21
S
RQ
PU32
Pull-up
transistor
Note1
D5/INT Note2
Note1
External 0 interrupt
Key-on wakeup input
Timer 1 count start
synchronous circuit input
External 0 interrupt circuit
Note5
Notes 1.
This symbol represents a parasitic diode on the port.
2. Applied potential to these ports must be VDD or less.
3. i represents bits 0 to 3.
4. j represents bits 0 to 1.
5. As for details, refer to the external interrupt structure.
Fig 3. Port block diagram (1)
Rev.1.01 Feb 15, 2008 Page 9 of 146
REJ03B0224-0101