Contents
GPIB-COM User Manual viii © National Instruments Corporation
Line Control Register.......................................................................................... 5-8
Modem Control Register.................................................................................... 5-10
Line Status Register............................................................................................ 5-12
Modem Status Register....................................................................................... 5-14
Programming the Serial Adapter.................................................................................... 5-16
Polling Method................................................................................................... 5-16
Interrupt-Driven Method..................................................................................... 5-16
The GPIB-COM Controller Function............................................................................. 5-17
Appendix ASpecifications....................................................................................................................... A-1
Appendix BMultiline Interface Command Messages.................................................................. B-1
Appendix COperation of the GPIB...................................................................................................... C-1
History of the GPIB........................................................................................................ C-1
Types of Messages......................................................................................................... C-1
Talkers, Listeners, and Controllers.................................................................................. C-1
System Controller and Active Controller........................................................................ C-2
GPIB Signals.................................................................................................................. C-2
Data Lines....................................................................................................................... C-3
Handshake Lines............................................................................................................. C-3
NRFD (not ready for data).................................................................................. C-3
NDAC (not data accepted).................................................................................. C-3
DAV (data valid)................................................................................................ C-4
Interface Management Lines........................................................................................... C-4
ATN (attention)................................................................................................... C-4
IFC (interface clear)............................................................................................ C-4
REN (remote enable).......................................................................................... C-4
SRQ (service request)......................................................................................... C-4
EOI (end or identify).......................................................................................... C-4
Physical and Electrical Characteristics............................................................................ C-5
Configuration Restrictions.............................................................................................. C-7