National Instruments 320174B-01 Chapter 3 Theory of Operation

© National Instruments Corporation 3-1 Lab-NB User Manual
Chapter 3
Theory of Operation
This chapter contains a functional overview of the Lab-NB and explains the operation of each
functional unit making up the Lab-NB.
Functional Overview
The block diagram in Figure 3-1 shows a functional overview of the Lab-NB board.
Data/
Address
12-Bit
D/A
12-Bit
D/A
1-MHz
Timebase
2-MHz
Timebase
Control
Signals
12
12
88253
Ctr/Timer
Group B
NuBus
Interface
FIFO
16
8253
Ctr/Timer
Group A
82C55A
Digital
Interface
8
Input
Max
Pgm
Gain
12-Bit
A/D
÷ 10
÷ 5
10-MHz
Clock
12 1
1
NuBus
Back Panel Connector
Figure 3-1. Lab-NB Block Diagram