Hardware and Software Configuration
Appendix C
GPIB-PCII/IIA for Graphics
C-18
© National Instruments Corp.
Table C-5. DMA Channels for the GPIB-PCII/IIA
Signal Lines
DMA
Channel
DMA
Acknowledge
DMA
Request
1
DACK1
DRQ1
2
DACK2
DRQ2
3
DACK3
DRQ3
You must position two jumpers to select a DMA channel. One jumper selects
the DMA Request line, and the other selects the DMA Acknowledge line. You
must move these two jumpers as a pair, and the DMA Acknowledge and DMA
Request lines that you select must have the same numeric suffix for proper
operation.
Figure C-8 shows the jumper position for the default DMA channel setting,
DMA channel 1.
DRQ3
DRQ1
DACK1
DRQ2
DACK2
DACK3
Figure C-8. DMA Channel Jumper Setting for DMA Channel 1
If you do not want to use DMA for GPIB transfers (the GPIB-PCII/IIA
alternatively can use programmed I/O transfers), you must logically disconnect
the GPIB-PCII/IIA from the DMA lines by selecting
NONE
for the DMA line
when you run the software configuration program, as explained in Step 3.
Configure the Software, later in this appendix. The board can remain in the back
panel and no jumpers have to be moved or changed.
