Hitachi H8S/2670, Reference Manual

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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 6 5 4 3 2 1 0
— — P85 P84 P83 P82 P81 P80
Initial value
Undefined Undefined
— * — * — * — * — * — *
Read/Write — — R R R R R R
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.