User manual

© National Instruments Corporation 4-1 PC-DIO-96/PnP User Manual
Theory of Operation
Chapter
4
This chapter contains a functional overview of the PC-DIO-96PnP
board and explains the operation of each functional unit making up the
PC-DIO-96PnP.
The block diagram in Figure 4-1 illustrates the key functional
components of the PC-DIO-96PnP board.
Figure 4-1. PC-DIO-96PnP Block Diagram
8
8
8
16
6
+5 VDC
8
8
8
8
8
8
8
8
8
8
8
8
Data 
Transceivers
PC I/O Channel 
Control Circuitry
Interrupt
Control
Circuitry
Plug and Play
Port A
Port B
Port C
Digital I/O Connector
PC I/O Channel
82C55A PPI
82C55A PPI
82C55A PPI
82C55A PPI
82C53 Timer
1 A Fuse
Port A
Port A
Port A
Port B
Port B
Port B
Port C
Port C
Port C
PC I/O
Address
Interrupt
Circuitry
INT