CHAPTER 2 PIN FUNCTIONS
2.2.7 P70 to P72 (Port 7)
These pins constitute a 3-bit I/O port. Port 7 can be set in the input or output mode in 1-bit units by port mode
register 7 (PM7). When used as an input port, use of an on-chip pull-up resistor can be specified by pull-up resistor
option register B7 (PUB7) in port units.
2.2.8 P80, P81 (Port 8)Note
These pins constitute a 2-bit I/O port. Port 8 can be set in the input or output mode in 1-bit units by port mode
register 8 (PM8). When used as an input port, use of an on-chip pull-up resistor can be specified by pull-up resistor
option register B8 (PUB8) in port units.
Note Only the µPD789426 and µPD789436 Subseries.
2.2.9 P90 to P97 (Port 9)Note
These pins constitute an 8-bit I/O port. Port 9 can be set in the input or output mode in 1-bit units by port mode
register 9 (PM9). When used as an input port, use of an on-chip pull-up resistor can be specified by pull-up resistor
option register B9 (PUB9) in port units.
Note Only the µPD789426 and µPD789436 Subseries.
2.2.10 S0 to S14Note
These pins are segment signal output pins for the LCD controller/driver.
Note S0 to S4 in the case of the µPD789426 and 789436 Subseries
2.2.11 COM0 to COM3
These pins are common signal output pins for the LCD controller/driver.
2.2.12 VLC0 to VLC2
These pins are power supply voltage pins to drive the LCD.
2.2.13 CAPH, CAPL
These pins are capacitor connection pins to drive the LCD.
2.2.14 RESET
This pin inputs an active-low system reset signal.
2.2.15 X1, X2
These pins are used to connect a crystal resonator for main system clock oscillation.
To supply an external clock, input the clock to X1 and input the inverted signal to X2.
2.2.16 XT1, XT2
These pins are used to connect a crystal resonator for subsystem clock oscillation.
To supply an external clock, input the clock to XT1 and input the inverted signal to XT2.
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User’s Manual U15075EJ1V0UM00
NEC [ NEC ]
