Port 0 - NEC PD789860 User Manual

6.2.1 Port 0

This is an 8-bit I/O port with an output latch. Port 0 can be set to input or output mode in 1-bit units by using port
mode register 0 (PM0).
RESET input sets port 0 to input mode.
Figure 6-1 shows a block diagram of port 0.
RD
WR
PORT
WR
PM
PM: Port mode register
RD: Port 0 read signal
WR: Port 0 write signal
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CHAPTER 6 PORT FUNCTIONS
Figure 6-1. Block Diagram of P00 to P07
Output latch
(P00 to P07)
PM00 to PM07
User's Manual U14826EJ5V0UD
P00 to P07