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CHAPTER 3 PIN FUNCTION (
µ
PD78058F SUBSERIES)
(1) Port mode
These ports function as 8-bit input/output ports. They can be specified bit-wise as input or output ports with
port mode register 6 (PM6).
P60 to P63 are N-ch open drain outputs. Mask ROM version can contain pull-up resistors with the mask option.
When P64 to P67 are used as input ports, on-chip pull-up resistors can be used by defining the pull-up resistor
option register L (PUOL).
(2) Control mode
These ports function as control signal output pins (RD, WR, WAIT, ASTB) in external memory expansion mode.
When a pin is used as a control signal output, the on-chip pull-up resistor is automatically disabled.
Caution When external wait is not used in external memory expansion mode, P66 can be used as an
input/output port.
3.2.8 P70 to P72 (Port 7)
This is a 3-bit input/output port. In addition to its use as an input/output port, it also has serial interface data input/
output and clock input/output functions.
The following operating modes can be specified bit-wise.
(1) Port mode
Port 7 functions as a 3-bit input/output port. Bit-wise specification as an input port or output port is possible
by means of port mode register 7 (PM7). When used as input ports, on-chip pull-up resistors can be used
by defining the pull-up resistor option register L (PUOL).
(2) Control mode
Port 7 functions as serial interface data input/output and clock input/output.
(a) SI2, SO2
Serial interface serial data input/output pins
(b) SCK2
Serial interface serial clock input/output pin.
(c) RxD, TxD
Asynchronous serial interface serial data input/output pins.
(d) ASCK
Asynchronous serial interface serial clock input/output pin.
Caution When this port is used as a serial interface pin, the I/O and output latches must be set
according to the function the user requires.
For the setting, refer to Table 19-2 “Serial Interface Channel 2 Operating Mode Settings of
List”.