
CHAPTER 2 PIN FUNCTIONS
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User’s Manual U13952EJ3V1UD
2.2.6 P80 to P87 (Port 8)
These pins constitute an 8-bit I/O port.
In addition to I/O port pins, these pins can also function as LCD
controller/driver segment signal.
The following operation modes can be specified in 1-bit units.
(1)
Port mode
In this port mode, P80 to P87 function as an 8-bit I/O port. These pins can be set to input or output mode in
1-bit units by using port mode register 8 (PM8). When used as an input port pins, an on-chip pull-up resistor
can be used by setting pull-up resistor option register 2 (PU2).
(2)
Control mode
In this mode, P80 to P87 function as segment signal output pins (S20 to S27) for the LCD controller/driver.
2.2.7 P90 to P93 (Port 9)
These pins constitute a 4-bit I/O port.
In addition to I/O port pins, these pins can also function as LCD
controller/driver segment signal.
The following operation modes can be specified in 1-bit units.
(1)
Port mode
In this mode, P90 to P93 function as a 4-bit I/O port. These pins can be set to input or output mode in 1-bit
units by using port mode register 9 (PM9). When used as input port pins, an on-chip pull-up resistor can be
used by setting pull-up resistor option register 2 (PU2).
(2)
Control mode
In this mode, P90 to P93 function as segment signal output pins (S16 to S19) for the LCD controller/driver.
2.2.8 S0 to S15
These pins are segment signal output pins for the LCD controller/driver.
2.2.9 COM0 to COM3
These pins are common signal output pins for the LCD controller/driver.
2.2.10 VLC0 to VLC2
These pins are power supply voltage pins to drive the LCD.
2.2.11 BIAS
This pin supplies power to drive the LCD.
2.2.12 AVREF
This pin is the A/D converter reference voltage pin. Connect it to VDD0, VDD1, VSS0, or VSS1 when not using the A/D
converter.
2.2.13 AVDD
This pin is the A/D converter analog circuit power supply pin. Always keep it at the same potential as the VDD0 pin
(even when the A/D converter is not used).