UPD17015GS datasheet(36/120 Pages) NEC

Part #	UPD17015GS

Description	4-BIT SINGLE-CHIP MICROCONTROLLER FOR PORTABLE RADIOS

PDF	120 Pages

Scroll/Zoom	100%

Manufacturer	NEC [NEC]

Direct Link	http://www.nec.com/

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36 / 120 page

µPD17015

9.2

GENERAL-PURPOSE I/O PORTS (P0A0 and P0A1 pins)

9.2.1

Configurations of the I/O ports

The configurations of the I/O ports are shown below.

(1) P0A0 and P0A1 pin

VDD

Output

latch

I/O switching flag

Write instruction

Port register

(1 bit)

Read instruction

9.2.2

Using the I/O Port

The P0ABIO0 or P0ABIO1 flag of the LCD enable register sets the I/O port to input or output mode.

P0A0 and P0A1 pins are bit I/O ports, each bit of which (each pin) can be set to input or output mode.

To set the output data, write the data to the corresponding port register. To read the input data, execute an

instruction to read the data.

9.2.3

Control Registers of the I/O Ports

The P0ABIO0 and P0ABIO1 flags of the LCD enable register set P0A0 and P0A1 pins in input or output mode,

respectively.

Fig. 9-1 shows the configuration and functions of the LCD enable register.

UPD17015GS Datasheet(PDF) 36 Page - NEC