Intel 87C196CB Analog-To-Digital A/D Converter, 2. A/D Result ADRESULT Register - Read Format

Models: 8XC196NT 87C196CB

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AD_RESULT (Read)

ANALOG-TO-DIGITAL (A/D) CONVERTER

AD_RESULT (Read)

Address:

1FAAH

 

Reset State:

7F80H

The A/D result (AD_RESULT) register consists of two bytes. The high byte contains the eight most- significant bits from the A/D converter. The low byte contains the two least-significant bits from a ten- bit A/D conversion, indicates the A/D channel number that was used for the conversion, and indicates whether a conversion is currently in progress.

15

ADRLT9

ADRLT8

ADRLT7

ADRLT6

7

 

 

 

 

 

 

 

ADRLT1

ADRLT0

 

 

 

 

8

ADRLT5 ADRLT4 ADRLT3 ADRLT2

0

STATUS

ACH2

ACH1

ACH0

 

 

 

 

Bit

Bit

Function

Number

Mnemonic

 

 

 

 

15:6

ADRLT9:0

A/D Result

 

 

These bits contain the A/D conversion result.

 

 

 

5:4

Reserved. These bits are undefined.

 

 

 

3

STATUS

A/D Status

 

 

Indicates the status of the A/D converter. Up to 8 state times are required

 

 

to set this bit following a start command. When testing this bit, wait at

 

 

least the 8 state times.

 

 

0 = A/D is idle

 

 

1 = A/D conversion is in progress

 

 

 

2:0

ACH2:0

A/D Channel Number

 

 

These bits indicate the A/D channel number that was used for the

 

 

conversion. The 87C196CB has eight A/D channel inputs, numbered

 

 

0–7

 

 

 

Figure 6-2. A/D Result (AD_RESULT) Register — Read Format

6-3

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Intel 87C196CB Analog-To-Digital A/D Converter, 2. A/D Result ADRESULT Register - Read Format, ADRESULT Read, Function