4507_M Datasheet, PDF (118/216 Pages) Renesas Technology Corp – 4-BIT CISC SINGLE-CHIP MICROCOMPUTER 4500 SERIES

4507 Group
APPLICATION
2.1 I/O pins
(3) Port P2
Port P2 is a 2-bit I/O port.
Also, its key-on wakeup function is switched to ON/OFF by the register K20 and K21, and its pull-
up transistor function is switched to ON/OFF by the register PU20 and PU21.
s Input/output of port P2
q Data input to port P2
Set the output latch of specified port P2i (i=0, 1) to “1” with the OP2A instruction. If the output
latch is set to “0,” “L” level is input.
The state of port P2 is transferred to register A when the IAP2 instruction is executed.
However, port P2 is 2 bits and A2 and A3 are fixed to “0.”
q Data output from port P2
The contents of register A is output to port P2 with the OP2A instruction.
The output structure is an N-channel open-drain.
(4) Port P3
Port P3 is a 2-bit I/O port.
s Input/output of port P3
q Data input to port P3
Set the output latch of specified port P3i (i=0, 1) to “1” with the OP3A instruction. If the output
latch is set to “0,” “L” level is input.
The state of port P3 is transferred to register A when the IAP3 instruction is executed.
However, port P3 is 2 bits and A2 and A3 are fixed to “0.”
q Data output from port P3
The contents of register A is output to port P3 with the OP3A instruction.
The output structure is an N-channel open-drain.
Rev.2.01 Feb 04, 2005
2-3
REJ09B0195-0201