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User’s Manual U12697EJ3V0UM
CHAPTER 2 PIN FUNCTIONS
(2) P10 to P17 (Port 1)
These pins constitute an 8-bit input-only port. In addition to general-purpose input port pins, they also function
as the analog inputs for the A/D converter.
On-chip pull-up resistors are not available.
(a) Port mode
These pins function as an 8-bit input-only port.
(b) Control mode
These pins function as the analog input pins (ANI0 to ANI7) of the A/D converter. The values are undefined
when the pins specified for analog input are read.
(3) P20 to P27 (Port 2)
These pins constitute an 8-bit I/O port. In addition to I/O port pins, they also function as the data I/O, clock
I/O, clock output, and buzzer output of the serial interface.
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
2 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 2.
(b) Control mode
These pins function as the data I/O pins, clock I/O pins, clock output pins, and buzzer output pins of the serial
interface.
Pins P25 to P27 can be specified as N-channel open drain by the port function control register (PF2) (only
in the
µ
PD784225Y Subseries).
(i)
SI0, SI1, SO0, SO1, SDA0
Note
These pins are the I/O pins for serial data in the serial interface.
(ii)
SCK0, SCK1, SCL0
Note
These pins are the I/O pins for the serial clock of the serial interface.
(iii) RxD1, TxD1
These pins are the I/O pins for serial data in the asynchronous serial interface.
Note
Only in the
µ
PD784225Y Subseries
