NEC uPD78056Y - Manual (Page 84)

84
CHAPTER 4 PIN FUNCTION (
µ
PD78054Y Subseries)
4.2.8 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 in 1-bit units.
(1) Port mode
Port 7 functions as a 3-bit input/output port. 1-bit-units 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, the I/O and output latches must be set according
to the function the user requires.
For the setting, see to the operation mode setting list in Table 19-2 “Serial Interface Channel
2”.
4.2.9 P120 to P127 (Port 12)
These are 8-bit input/output ports. Besides serving as input/output ports, they function as a real-time output port.
The following operating modes can be specified in 1-bit units.
(1) Port mode
These ports function as 8-bit input/output ports. They can be specified in 1-bit units as input or output ports
with port mode register 12 (PM12). When they are used as input ports, on-chip pull-up resistors can be used
by defining the pull-up resistor option register H (PUOH).
(2) Control mode
These ports function as real-time output ports (RTP0 to RTP7) outputting data in synchronization with a trigger.