Single-Chip Microcontrollers User's Manual

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CHAPTER 4 PIN FUNCTION (
ยต
PD78058FY SUBSERIES)
4.2.4 P30 to P37 (Port 3)
These are 8-bit input/output ports. Beside serving as input/output ports, they function as timer input/output, clock
output, and buzzer output.
The following operating modes can be specified bit-wise.
(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 3 (PM3). When they 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 timer input/output, clock output, and buzzer output.
(a) TI1 and TI2
Pin for external count clock input to the 8-bit timer/event counter.
(b) TO0 to TO2
Timer output pins.
(c) PCL
Clock output pin.
(d) BUZ
Buzzer output pin.