HD6473032F Datasheet, PDF (142/572 Pages) Hitachi Semiconductor – Hitachi Microcomputer

7.3.2 Register Descriptions
Table 7-3 summarizes the registers of port 2.
Table 7-3 Port 2 Registers
Address* Name
Abbreviation R/W
H'FFC1
Port 2 data direction register
P2DDR
W
H'FFC3
Port 2 data register
P2DR
R/W
H'FFD8
Port 2 input pull-up control register P2PCR
R/W
Note: * Lower 16 bits of the address.
Initial Value
H'00
H'00
H'00
Port 2 Data Direction Register (P2DDR): P2DDR is an 8-bit write-only register that can select
input or output for each pin in port 2.
Bit
Initial value
Read/Write
7
6
5
4
3
2
1
0
P2₇DDR P2₆DDR P2₅DDR P2₄DDR P2₃DDR P2₂DDR P2₁DDR P2₀DDR
0
0
0
0
0
0
0
0
W
W
W
W
W
W
W
W
Port 2 data direction 7 to 0
These bits select input or
output for port 2 pins
Mode 1: A pin in port 2 becomes an address output pin if the corresponding P2DDR bit is set to 1,
and a generic input pin if this bit is cleared to 0.
Modes 2 and 3: Port 2 functions as an input/output port. A pin in port 2 becomes an output pin if
the corresponding P2DDR bit is set to 1, and an input pin if this bit is cleared to 0.
P2DDR is a write-only register. Its value cannot be read. All bits return 1 when read.
P2DDR is initialized to H'00 by a reset and in hardware standby mode. In software standby mode it
retains its previous setting. If a P2DDR bit is set to 1, the corresponding pin maintains its output
state in software standby mode.
127