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CHAPTER 2 PIN FUNCTIONS
User’s Manual U15017EJ2V0UD
2.2 Pin Functions
2.2.1 P00 to P03 (Port 0)
P00 to P03 constitute a 4-bit input port. These pins function alternately as A/D converter analog inputs.
The following operation modes can be specified in 1-bit units.
(1) Port mode
In this mode, P00 to P03 function as a 4-bit input port.
(2) Control mode
In this mode, P00 to P03 function as A/D converter analog input pins (ANI8 to ANI11).
2.2.2 P10 to P17 (Port 1)
P10 to P17 constitute an 8-bit input port. These pins function alternately as A/D converter analog inputs.
The following operation modes can be specified in 1-bit units.
(1) Port mode
In this mode, P10 to P17 functions as an 8-bit input port.
(2) Control mode
In this mode, P10 to P17 function as analog input pins (ANI0 to ANI7) of the A/D converter.
2.2.3 P20, P25 to P27 (Port 2)
P20 and P25 to P27 constitute a 4-bit I/O port. These pins function alternately as data input/output for serial
interface 0, asynchronous serial interface, clock, and data input for the timer signal.
The following operation modes can be specified in 1-bit units.
(1) Port mode
In this mode, P20 and P25 to P27 function as a 4-bit I/O port. These pins can be set in the input or output
mode in 1-bit units by using the port 2 mode register (PM2). The on-chip pull-up resistor can be specified in
1-bit units using the pull-up resistor option register 2 (PU2).
(2) Control mode
In this mode, P20 and P25 to P27 function as data input/output for serial interface 0, the asynchronous serial
interface, the clock, and data input for the timer signal.
(a) SI0, SO0
These are serial data I/O pins of the serial interface 0.
(b) SCK0
This is a serial clock I/O pin of the serial interface 0.
(c) TI00
This is a timer input pin of 16-bit timer counter 0 (TM0).
(d) R
X
D0, T
X
D0
These are serial data I/O pins of the asynchronous serial interface.