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Chapter 4 theory of operation, Functional overview, Figure 4-1. lab-pc+ block diagram – National Instruments Low-Cost Multifunction I/O Board for ISA Lab-PC+ User Manual

Page 60: Figure 4-1, Lab-pc+ block diagram

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© National Instruments Corporation

4-1

Lab-PC+ User Manual

Chapter 4
Theory of Operation

This chapter contains a functional overview of the Lab-PC+ and explains the operation of each
functional unit making up the Lab-PC+. This chapter also explains the basic operation of the
Lab-PC+ circuitry.

Functional Overview

The block diagram in Figure 4-1 shows a functional overview of the Lab-PC+ board.

Data/

Address

12-Bit

D/A

12-Bit

D/A

1-MHz

Timebase

2 MHz

Timebase

Control

Signals

12

12

8

8253

Ctr/Timer

Group B

PC I/O

Channel

Interface

FIFO

16

8253

Ctr/Timer

Group A

8255A

Digital

Interface

8

Input

Mux

Pgm
Gain

12-Bit

A/D

ч

10

ч

5

10 MHz
Oscillator

12

1

1

PC I/O Channel

Back P

anel Connector

Input

Mux

Figure 4-1. Lab-PC+ Block Diagram