Datasheet

Table Of Contents
Section 9 I/O Ports
REJ09B0140-0900 Rev. 9.00 Page 233 of 846
Sep 16, 2010
H8S/2215 Group
9.1 Port 1
Port 1 is an 8-bit I/O port. The port 1 has the following registers.
Port 1 data direction register (P1DDR)
Port 1 data register (P1DR)
Port 1 register (PORT1)
9.1.1 Port 1 Data Direction Register (P1DDR)
P1DDR is an 8-bit write-only register, the individual bits of which specify input or output for the
pins of port 1. Since this is a write-only register, bit manipulation instructions should not be used
to write to it. For details, see section 2.9.4, Accessing Registers Containing Write-Only Bits.
Bit Bit Name Initial Value R/W Description
7 P17DDR 0 W
6 P16DDR 0 W
5 P15DDR 0 W
4 P14DDR 0 W
3 P13DDR 0 W
2 P12DDR 0 W
1 P11DDR 0 W
0 P10DDR 0 W
Modes 4 to 6
If address output is enabled by the setting of bits AE3 to
AE0 in PFCR, pins P13 to P10 are address outputs. Pins
P17 to P14, and pins P13 to P10 when address output is
disabled, are output ports when the corresponding
P1DDR bits are set to 1, and input ports when the
corresponding P1DDR bits are cleared to 0.
Mode 7
Setting a P1DDR bit to 1 makes the corresponding port 1
pin an output port, while clearing the bit to 0 makes the
pin an input port.