![background image](http://html.mh-extra.com/html/national-instruments/gpib-130/gpib-130_user-manual_709644021.webp)
Configuration and Operation
Chapter 3
GPIB-130 User Manual
3-4
© National Instruments Corporation
Both GPIB-130s in the extension system do not need to be set to the same PPR mode. The PPR
mode of the local GPIB-130 should be chosen to accommodate the Controllers on the local GPIB
system. Likewise, the PPR mode of the remote GPIB-130 should be chosen to accommodate the
Controllers on the remote GPIB system. If no Controllers are physically connected to one of the
GPIB-130s, the PPR mode of that GPIB-130 has no effect on the system.
Setting the PPR Mode
Use switch position 2 on the side of each GPIB-130 to set the PPR mode. Slide the switch to the
up position to set Immediate PPR mode; slide the switch down to set Stored PPR mode. See
Figure 3-2.
On Of
f
. . . . . . . . . . . .
A. Immediate PPR Mode
(Default)
B. Stored PPR Mode
On Of
f
. . . . . . . . . . . .
PPoll Imm.
PPoll Stored
uffered
uffered
PPoll Imm.
PPoll Stored
uffered
uffered
Key
= PPoll position
= Buffer position
Figure 3-2. Switch Setting for Parallel Poll Response (PPR) Mode
Operating the GPIB-130 System
The GPIB-130 extension system is fully operational when power is applied to both units. In
some systems, it is necessary to power on the System Controller device last, after the extenders
and all other devices are operating. This power-on sequence is necessary if the System
Controller executes only one IFC shortly after power-on.
The GPIB-130 has four indicator LEDs on the top of the box labeled Power, Link, Talk, and
Listen.
Power LED
The Power LED is lit whenever power is applied to the GPIB-130 and the power switch on the
side of the box is in the on position.