Chapter 1
Introduction
© National Instruments Corporation
1-3
GPIB-130 User Manual
With the GPIB-130, it is possible to overcome the following two configuration restrictions
imposed by ANSI/IEEE Standard 488.1-1987:
•
A cable length limit of 20 m total per contiguous bus or 2 m times the number of devices on
the bus, whichever is smaller
•
An electrical loading limit of 15 devices per contiguous bus
Each GPIB-130 system extends the distance limit by 300 m and the loading limit to 30 devices
(including the extenders), without sacrificing speed or performance. These point-to-point
extender systems can be connected in series for longer distances or in star patterns for additional
loading.
The maximum data transfer rate over the extension is 900 kbytes/sec. Furthermore, there is no
speed degradation at all for transfers between devices on the same side of the extension.
Because the GPIB-130 is a functionally transparent extender, the same GPIB communications
and control programs that work with an unextended system can work unmodified with an
extended system. There is one minor exception to this transparency in conducting parallel polls,
as explained in Chapter 3 in the section Parallel Poll Response (PPR) Modes.
What Your Kit Should Contain
Your GPIB-130 kit should contain the following components:
Kit Component
Part Number
GPIB-130 Bus Extender
181460-01
One of the following power supplies:
• 100-120 VAC (5V-regulated, 700mA)
or
• 220-240 VAC (5V-regulated, 1A)
181626-01
181626-31
GPIB-130 User Manual
320391-01