© National Instruments Corporation vii GPIB-120A User Manual
ContentsAbout This Manual...............................................................................................................ix
Organization of This Manual...........................................................................................ix
Conventions Used in This Manual...................................................................................ix
Related Documentation....................................................................................................x
Customer Communication ...............................................................................................x
Chapter 1
Introduction............................................................................................................................1-1
Description of the GPIB-120A ........................................................................................1-1
What You Need to Get Started ........................................................................................1-3
Optional Equipment.........................................................................................................1-3
Unpacking Your GPIB-120A...........................................................................................1-3
Chapter 2
Connection...............................................................................................................................2-1
Isolation Considerations...................................................................................................2-1
Placing Your Instruments.................................................................................................2-2
Connecting the GPIB-120A.............................................................................................2-2
Connecting to Hewlett-Packard Controllers........................................................2-2
Mounting the GPIB-120A................................................................................................2-2
Chapter 3
Theory of Operation ............................................................................................................3-1
Circuitry of the GPIB-120A.............................................................................................3-1
The GPIB-120A Front Panel............................................................................................3-2
Power On..............................................................................................................3-2
System Controller Detection................................................................................3-2
Active Controller Detection.................................................................................3-2
Source Handshake Detection...............................................................................3-2
Data Direction Control.........................................................................................3-3
Parallel Poll Detection .........................................................................................3-3
Acceptable Identification Codes......................................................................................3-4
Appendix A
Operation of the GPIB........................................................................................................A-1
History of the GPIB .........................................................................................................A-1
GPIB Operation................................................................................................................A-1
Types of Messages...............................................................................................A-1
Talkers, Listeners, and Controllers......................................................................A-2
The Controller-In-Charge and System Controller ...............................................A-2
GPIB Signals and Lines.......................................................................................A-3
Data Lines................................................................................................A-3
Handshake Lines......................................................................................A-3
NRFD (Not Ready For Data).......................................................A-3