UPD784020 Datasheet, PDF (12/90 Pages) NEC – 16/8-BIT SINGLE-CHIP MICROCOMPUTER

mPD784020, 784021
6. LIST OF PIN FUNCTIONS
6.1 PORT PINS
Pin
P00-P07
P10
P11
P12
P13
P14
P15-P17
P20
P21
P22
P23
P24
P25
P26
P27
P30
P31
P32
P33
P34-P37
P60-P63
P66
P67
P70-P77
I/O
I/O
I/O
Input
I/O
I/O
I/O
Dual-function
Function
—
Port 0 (P0):
Ý 8-bit I/O port
Ý Functions as a real-time output port (4 bits ¥ 2).
Ý Inputs and outputs can be specified bit by bit.
Ý The use of the pull-up resistors can be specified by software for the pins
in the input mode together.
Ý Can drive a transistor.
PWM0
Port 1 (P1):
PWM1
Ý 8-bit I/O port
ASCK2/SCK2
Ý Inputs and outputs can be specified bit by bit.
RxD2/SI2
TxD2/SO2
—
Ý The use of the pull-up resistors can be specified by software for the pins
in the input mode together.
Ý Can drive LED.
NMI
Port 2 (P2):
INTP0
Ý 8-bit input-only port
INTP1
INTP2/CI
INTP3
INTP4/ASCK/SCK1
INTP5
SI0
Ý P20 does not function as a general-purpose port (nonmaskable inter-
rupt). However, the input level can be checked by an interrupt service
routine.
Ý The use of the pull-up resistors can be specified by software for pins
P22 to P27 (in units of 6 bits).
Ý The P25/INTP4/ASCK/SCK1 pin functions as the SCK1 output pin by
CSIM1.
RxD/SI1
Port 3 (P3):
TxD/SO1
Ý 8-bit I/O port
SCK0
Ý Inputs and outputs can be specified bit by bit.
SO0/SB0
TO0-TO3
Ý The use of the pull-up resistors can be specified by software for the pins
in the input mode together.
A16-A19
Port 6 (P6):
WAIT/HLDRQ
Ý P60 to P63 are an output-only port.
Ý Inputs and outputs can be specified bit by bit for pins P66 and P67.
REFRQ/HLDAK
Ý The use of the pull-up resistors can be specified by software for the pins
in the input mode together.
ANI0-ANI7
Port 7 (P7):
Ý 8-bit I/O port
Ý Inputs and outputs can be specified bit by bit.
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