Pin Functions - Hitachi H8S/2678 Series Reference Manual

P8DR is initialized to H'00 by a reset and in hardware standby mode. It retains its prior state in
software standby mode.
Port 8 Register (PORT8)
Bit 7
—
Initial value
Undefined Undefined
Read/Write —
Note: * Determined by the state of pins P85 to P80.
PORT8 is a 6-bit read-only register that shows the pin states. PORT8 cannot be written to; writing
of output data for the port 8 pins (P85 to P80) must always be performed on P8DR.
Bits 7 and 6 are reserved; if read they will return an undefined value.
If a port 8 read is performed while P8DDR bits are set to 1, the P8DR values are read. If a port 8
read is performed while P8DDR bits are cleared to 0, the pin states are read.
After a reset and in hardware standby mode, PORT8 contents are determined by the pin states, as
P8DDR and P8DR are initialized. PORT8 retains its prior state in software standby mode.
5.9.3

Pin Functions

Port 8 pins also function as interrupt input pins (IRQ0 to IRQ5) and EXDMAC input/output pins
(EDREQ2, ETEND2, EDACK2, EDREQ3, ETEND3, and EDACK3). Port 8 pin functions are
shown in table 5.16.
242
6 5
— P85
—*
— R
4 3
P84 P83
—* —*
R R
2 1
P82 P81
—* —*
R R
0
P80
—*
R