Adding the DMA Description Item

The CX2590 requires one DMA channel for NORMAL operation. The CX2590 can use either DMA channel 0, 1, 2, or 3 and the DMA bus width is eight bits.

To add the DMA requirements to the XSCSI.INF file for the CX2590:

1. Right-click on the CX2590_DMA subfolder under the Log Config Sections folder and select the Add DMA Descriptor option. This will create an DMA Descriptor subfolder.
2. Double-click on the new subfolder.

An array of DMAs and Yes/No values appears in the edit area. Double-click on individual DMA item names to set DMA channels 0, 1, 2, and 3 to Yes and all other DMAs to No. In this example, there is no need to change the default DMA bus width of 8 bits. When you are done, the DMA array will look like this:

Item             Value
  DMA Bus Width    8 bits
  DMA  0           Yes
  DMA  1           Yes
  DMA  2           Yes
  DMA  3           Yes
  DMA  4           No
  DMA  5           No
  DMA  6           No
  DMA  7           No
 

Note that given the requirements in this example, adding this DMA descriptor to the INF file does not satisfy all the DMA requirements for this example. The DMA requirements are:

"One DMA channel, although the board will work without one."

In order to meet the requirement "the board will work without one," you will have to add another logical configuration section to the INF file, with priority set to SUBOPTIMAL and with no DMA item. The method for doing this is shown in the next section.