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CHAPTER 2 PIN FUNCTIONS
User’s Manual U14701EJ3V0UD
2.2.3 P20 to P25 (Port 2)
These are 6-bit I/O ports. Besides serving as I/O ports, they function as serial interface data I/O and clock I/O.
The following operation modes can be specified in 1-bit units.
(1) Port mode
These ports function as 6-bit I/O ports. They can be specified as input or output ports in 1-bit units with port
mode register 2 (PM2). On-chip pull-up resistors can be used by setting pull-up resistor option register 2 (PU2).
(2) Control mode
These ports function as serial interface data I/O and clock I/O functions.
(a) SI1, SI3, SO1, and SO3
Serial interface serial data I/O pins.
(b) SCK1 and SCK3
Serial interface serial clock I/O pins.
(c) R
X
D0 and T
X
D0
Asynchronous serial interface serial data I/O pins.
2.2.4 P30 to P34 (Port 3)
These are 5-bit I/O ports. Besides serving as I/O ports, they function as timer I/O.
(1) Port mode
These ports function as 5-bit I/O ports. They can be specified as input or output ports in 1-bit units with port
mode register 3 (PM3). On-chip pull-up resistors can be used by setting pull-up resistor option register 3 (PU3).
P31 and P32 are also capture trigger signal input pins to the capture registers (CR00 and CR01) of the 16-bit
timer/event counter 0 with a valid edge input.
(2) Control mode
These ports function as timer I/O.
(a) TI00
External count clock input pin to 16-bit timer/event counter 0 and capture trigger signal input pin to capture
registers (CR00 and CR01) of the 16-bit timer/event counter 0.
(b) TI01
Capture trigger signal input pin to capture register (CR00) of the 16-bit timer/event counter 0.
(c) TI50 and TI51
External count clock input pins to 8-bit timer/event counters 50 and 51.
(d) TO0, TO50, and TO51
Timer output pins.