
CHAPTER 2 PIN FUNCTIONS
Preliminary User’s Manual U16228EJ1V0UD
50
2.2.9 P120 (port 12)
P120 functions as a 1-bit I/O port. This pin also functions as a pin for external interrupt request input.
The following operation modes can be specified.
(1) Port mode
P120 functions as a 1-bit I/O port. P120 can be set to input or output using port mode register 12 (PM12). Use of
an on-chip pull-up resistor can be specified by pull-up resistor option register 12 (PU12).
(2) Control mode
P120 functions as an external interrupt request input pin (INTP0) for which the valid edge (rising edge, falling
edge, or both rising and falling edges) can be specified.
2.2.10 P130 (port 13)
P130 functions as a 1-bit output-only port.
2.2.11 P140 and P141 (port 14)
P140 and P141 function as a 2-bit I/O port. These pins also function as external interrupt request input, clock
output, and buzzer output pins.
The following operation modes can be specified in 1-bit units.
(1) Port mode
P140 and P141 function as a 2-bit I/O port. P140 and P141 can be set to input or output in 1-bit units using port
mode register 14 (PM14). Use of an on-chip pull-up resistor can be specified by pull-up resistor option register 14
(PU14).
(2) Control mode
P140 and P141 function as external interrupt request input, clock output, and buzzer output pins.
(a) INTP6, INTP7
These are the external interrupt request input pins for which the valid edge (rising edge, falling edge, or both
rising and falling edges) can be specified.
(b) PCL
This is a clock output pin.
(c) BUZ
This is a buzzer output pin.
2.2.12 AVREF
This is the A/D converter reference voltage input pin.
When A/D converter is not used, connect this pin to VDD.
2.2.13 AVSS
This is the A/D converter ground potential pin. Even when the A/D converter is not used, always use this pin with
the same potential as the EVSS pin or VSS pin.