Appendix C
Hardware and Software Configuration
© National Instruments Corp.
C-19
GPIB-PCII/IIA for Graphics
Note:
Disabling DMA will decrease performance substantially.
If you change the DMA jumper setting from the default setting, record the new
setting on the GPIB-PCII/IIA Hardware and Software Configuration Form in
Appendix E, Customer Communication. Remember that you must run the
IBDIAG
diagnostic program and configure the software, as explained later in
this appendix, after you change any hardware configuration settings.
Possible Conflicts
There are only three DMA channels that can be used by the GPIB-PCII/IIA
interface board. If any device uses DMA channel 1, change the DMA channel
used by either the GPIB-PCII/IIA or the other device to DMA channel 2 or 3. If
no DMA channel is available, configure the software to run without DMA using
the software configuration program.
Shield Ground Configuration
The GPIB-PCII/IIA is set at the factory with the jumper in place to connect the
logic ground of the GPIB-PCII/IIA to its shield ground. This configuration
minimizes the EMI emissions.
Caution:
The GPIB-PCII/IIA was tested for compliance with FCC
standards with the shield ground connected to logic ground.
Removing the jumper might cause EMI emissions to exceed any
or all of the applicable standards.
If your application requires that logic ground be disconnected from shield
ground, refer to Figure C-1 to locate the shield ground jumper W1 on the GPIB-
PCII/IIA. Remove the jumper and place it across only one of the jumper pins,
as shown in Figure C-9.