CHAPTER 2 PIN FUNCTIONS
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User’s Manual U11302EJ4V0UM
2.2 Description of Pin Functions
2.2.1 P00 to P04 (Port 0)
These pins constitute a 5-bit I/O port. Besides serving as I/O port pins, they function as external interrupt request
inputs, an external count clock input to the timer, a capture trigger signal input, and crystal resonator connection for
subsystem clock oscillation.
The following operating modes can be specified in 1-bit units.
(1) Port mode
P00 and P04 function as input-only port pins and P01 to P03 function as I/O port pins.
P01 to P03 can be specified in input or output mode in 1-bit units using port mode register 0 (PM0). When they
are used as input port pins, an on-chip pull-up resistor can be used by setting the pull-up resistor option register
(PUO).
(2) Control mode
P00 to P04 function as external interrupt request inputs, an external count clock input to the timer, and crystal
connection for subsystem clock oscillation.
(a) INTP0 to INTP3
INTP0 to INTP2 are external interrupt request input pins for which valid edges can be specified (rising edge,
falling edge, and both rising and falling edges). INTP0 becomes a 16-bit timer/event counter capture trigger
signal input pin with a valid edge input. INTP3 becomes a falling edge detection external interrupt request
input pin.
(b) TI0
TI0 is a pin for inputting the external count clock to the 16-bit timer/event counter.
(c) XT1
Crystal connection pin for subsystem clock oscillation
2.2.2 P10 to P17 (Port 1)
These pins constitute an 8-bit I/O port. Besides serving as I/O port pins, they function as A/D converter analog
inputs.
The following operating modes can be specified in 1-bit units.
(1) Port mode
P10 to P17 function as an 8-bit I/O port. They can be specified in input or output mode in 1-bit units using port
mode register 1 (PM1). When they are used as input port pins, an on-chip pull-up resistor can be used by setting
the pull-up resistor option register (PUO).
(2) Control mode
P10 to P17 function as A/D converter analog input pins (ANI0 to ANI7). The on-chip pull-up resistors are
automatically disabled when the pins are specified for analog input.
Содержание mPD780208 Subseries
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