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Chapter 10 a/d converter, 1 a/d converter functions, 2 a/d converter configuration – IBM uPD78082 User Manual

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CHAPTER 10 A/D CONVERTER

CHAPTER 10 A/D CONVERTER

10.1 A/D Converter Functions

The A/D converter converts an analog input into a digital value. It consists of 8 channels (ANI0 to ANI7) with an

8-bit resolution.

The conversion method is based on successive approximation and the conversion result is held in the 8-bit A/D

conversion result register (ADCR).

The following two ways are available to start A/D conversion.

(1) Hardware start

Conversion is started by trigger input (INTP3).

(2) Software start

Conversion is started by setting the A/D converter mode register.

Select 1 channel of analog input from ANI0 to ANI7 and perform A/D conversion. As for A/D conversion operations,

when the hardware is started up, the A/D conversion operation stops when A/D conversion is completed, and an

interrupt request (INTAD) is generated. In the case of software start, the A/D conversion operation is repeated. Each

time an A/D conversion operation ends, an interrupt request (INTAD) is generated.

10.2 A/D Converter Configuration

The A/D converter consists of the following hardware.

Table 10-1. A/D Converter Configuration

Item

Configuration

Analog input

8 Channels (ANI0 to ANI7)

Control register

A/D converter mode register (ADM)

A/D converter input select register (ADIS)

External interrupt mode register 1 (INTM1)

Register

Successive approximation register (SAR)

A/D conversion result register (ADCR)

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