SeaLevel ACB II 3061, Руководство пользователя

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Card Setup
Sealevel Systems ACB-II Page 4
DMA Channel Selection (Header E3)
The D irect M emory A ccess (DMA) Channel can be selected as Channel 1
or Channel 3. See the Appendix F for jumper position. If DMA is not used,
these jumpers should be removed.
DMA Channel 3
Selected
E3
DMA Channel 1
Selected
E3
Figure 3 - Header E3 DMA Selection
DMA Enable (Header E7)
Header E7 selects whether the DMA Tri-State drivers are enabled, disabled
or whether the RTS from Channel B is used to enable the DMA. The
‘A’
position selects the Always Enabled mode. The ‘B’ position selects RTSB
Enable . Please refer to the Zilog SCC User’s Manual for aid in
programming Write Register 5 for RTSB. Removing the jumper disables
the DMA drivers, and no DMA can be performed.
A
B
Figure 4 - Header E7 DMA Enable (Factory Default)