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Digital control register – National Instruments Low-Cost Multifunction I/O Board for ISA Lab-PC+ User Manual

Page 153

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Appendix D

Register Map and Descriptions

© National Instruments Corporation

D-37

Lab-PC+ User Manual

Digital Control Register

The Digital Control Register can be used to configure Port A, Port B, and Port C as inputs or
outputs as well as selecting simple mode (basic I/O) or handshaking mode (strobed I/O) for
transfers. See Programming the Digital I/O Circuitry in Appendix E, Register-Level
Programming,
for a description of the individual bits in the Digital Control Register.

Address:

Base address + 13 (hex)

Type:

Write-only

Word Size:

8-bit

Bit Map:

7

6

5

4

3

2

1

0

CW7

CW6

CW5

CW4

CW3

CW2

CW1

CW0

Bit

Name

Description

7-0

CW<7..0>

8-bit control word.