69CHAPTER 3 PIN FUNCTION (μPD78058F SUBSERIES)(1) Port modeThese ports function as 8-bit input/output ports. They can be specified bit-wise as input or output ports withport 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 resistoroption register L (PUOL).(2) Control modeThese 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 aninput/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 modePort 7 functions as a 3-bit input/output port. Bit-wise specification as an input port or output port is possibleby means of port mode register 7 (PM7). When used as input ports, on-chip pull-up resistors can be usedby defining the pull-up resistor option register L (PUOL).(2) Control modePort 7 functions as serial interface data input/output and clock input/output.(a) SI2, SO2Serial interface serial data input/output pins(b) SCK2Serial interface serial clock input/output pin.(c) RxD, TxDAsynchronous serial interface serial data input/output pins.(d) ASCKAsynchronous 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 setaccording to the function the user requires.For the setting, refer to Table 19-2 “Serial Interface Channel 2 Operating Mode Settings ofList”.
