CHAPTER 2 PIN FUNCTIONS
User’s Manual U12697EJ3V0UM
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(iv) ASCK1
This is the input pin for the baud rate clock of the asynchronous serial interface.
(v)
PCL
This is the clock output pin.
(vi) BUZ
This is the buzzer output pin.
(4) P30 to P37 (Port 3)
These pins constitute an 8-bit I/O port. In addition to I/O port pins, they also function as timer I/O.
The following operation modes can be specified in 1-bit units.
(a) Port mode
These pins function as an 8-bit I/O port. Input of output can be specified in 1-bit units by means of the port
3 mode register. Regardless of whether the input mode or output mode is specified, pull-up resistors can
be connected in 1-bit units using pull-up resistor option register 3.
(b) Control mode
These pins function as timer I/O.
(i)
TI00
This is the external clock input pin to the 16-bit timer/event counter.
This is also used as the capture trigger signal input pin to capture/compare registers 00 and 01.
(ii)
TI01
This is the capture trigger signal input pin to capture/compare register 00.
(iii) TI1, TI2
These are external clock input pins to the 8-bit timer counter.
(iv) TO0 to TO2
These are timer output pins.
(5) P40 to P47 (Port 4)
These pins constitute an 8-bit I/O port. In addition to I/O port pins, they also function as an address/data bus.
LEDs can be directly driven.
The following operation modes can be specified in 1-bit units.
(a) Port mode
These pins function as an 8-bit I/O port. Input or output can be specified in 1-bit units by means of the port
4 mode register. When used as an input port, pull-up resistors can be connected in 8-bit units with bit 4 (PUO4)
of the pull-up resistor option register.
(b) Control mode
These pins function as the lower address/data bus pins (AD0 to AD7) when in the external memory expansion
mode. If PUO4 = 1, pull-up resistors can be connected.
