PC Elite Reference
Installation Guide
apparently busy doing another job. DMA is ideal for moving
large amounts of data very quickly. The DMA hardware is
designed so that the ELITE board will only generate DMA
requests when the board is programmed to do perform DMA
input or output. This allows for DMA line sharing.
The position of the jumper MUST match the DMA channel
used in the software.
Setting The DMA Jumper Block.
_____________________________
Two movable jumpers on the DMA jumper block are used
to select the channel for direct memory access. For most users
the best position is the factory default, DMA 1.
Moving the jumper pins select which DMA channel is used
by the IEEE board hardware. The jumpers can be in one of three
positions, see Figure 2-5. The jumpers must be set in pairs, both
jumpers MUST be set in the same DMA channel pair.
NOTE: Do not add an extra jumpers of your own across the
jumper block, it will only cause great confusion.
Figure 2-5. The DMA Jumper Block.
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DMA CHANNEL SELECTION.
______________________
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DMA CHANNEL 1.
DEFAULT
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DMA CHANNEL 2.
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DMA CHANNEL 3.
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2-16
Chapter 2
