NEC PD750008 Manuale Utente

µPD750008 USER'S MANUAL

5.1.1 Types, Features, and Configurations of Digital I/O Ports

Table 5-1 lists the types of digital I/O ports.

Figures 5-2 to 5-6 show the configurations of the ports.

Table 5-1. Types and Features of Digital Ports

Port name

Function

Operation and feature

Remarks

(symbol)

PORT0

4-bit I/O

Also used as INT4, SCK, SO/SB0,
and SI/SB1.

PORT1

Also used as INT0 to INT2 and
TI0.

PORT3

Note 1

4-bit I/O

Also used as MD0 to MD3

Note 2

PORT6

Also used as KR0 to KR3.

PORT2

Also used as PTO0, PTO1, PCL,
and BUZ.

PORT7

Also used as KR4 to KR7.

PORT4

Note 1

4-bit I/O

Allows input or output mode setting in

Whether to use pull-up resistors

PORT5

Note 1

(N-ch open-drain;

units of 4 bits. Ports 4 and 5 can be

can be specified bit by bit with a

can withstand

paired, allowing data I/O in units of

mask option

Note 3

13V)

8 bits.

PORT8

2-bit I/O

Allows input or output mode setting in
units of 2 bits.

Notes 1. Can directly drive the LED.

2. Only for the µPD75P0016.

3. The µPD75P0016 does not have a mask option and cannot be connected with a pull-up resistor.

P10 is also used as an external vectored interrupt input pin. This input is provided with a noise eliminator.

(See Section 6.3 for details.)

When the RESET signal is generated, output latches of ports 2 to 8 are cleared to 0 and the output buffer

is turned off so that these ports are in the input mode.

Allows read and test at any timeregard
less of the operation modes of another
functions assigned to these pins.

Allows input or output mode setting bit
by bit.

Ports 6 and 7 can be paired, allowing
data I/O in units of 8 bits. Allows input
or output mode setting in units of 4 bits.