Datasheet

Section 8 I/O Ports
Rev. 4.00 Sep 27, 2006 page 256 of 1130
REJ09B0327-0400
Port 8 Data Direction Register (P8DDR)
Bit 76543210
P86DDR P85DDR P84DDR P83DDR P82DDR P81DDR P80DDR
Initial value10000000
Read/Write WWWWWWW
P8DDR is a 7-bit write-only register, the individual bits of which specify input or output for the
pins of port 8. P8DDR has the same address as PBPIN, and if read, the port B state will be
returned.
Setting a P8DDR bit to 1 makes the corresponding port 8 pin an output pin, while clearing the bit
to 0 makes the pin an input pin.
P8DDR is initialized to H'80 by a reset and in hardware standby mode. It retains its prior state in
software standby mode.
Port 8 Data Register (P8DR)
Bit 76543210
P86DR P85DR P84DR P83DR P82DR P81DR P80DR
Initial value10000000
Read/Write R/W R/W R/W R/W R/W R/W R/W
P8DR is a 7-bit readable/writable register that stores output data for the port 8 pins (P86 to P80). If
a port 8 read is performed while P8DDR bits are set to 1, the P8DR values are read directly,
regardless of the actual pin states. If a port 8 read is performed while P8DDR bits are cleared to 0,
the pin states are read.
P8DR is initialized to H'80 by a reset and in hardware standby mode. It retains its prior state in
software standby mode.
8.9.3 Pin Functions
Port 8 pins also function as SCI1 I/O pins (TxD1, RxD1, SCK1), the IIC1 I/O pin (SCL1), HIF
I/O pins (CS2, GA20, HA0, HIFSD), and external interrupt input pins (IRQ5 to IRQ3). The port 8
pin functions are shown in table 8.19.