National Instruments AT-DIO-32F, Руководство пользователя

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Configuration and Installation Chapter 2
AT-DIO-32F User Manual 2-8 © National Instruments Corporation
The AT-DIO-32F hardware can only use Channels 5, 6, and 7 as DMA channels. Notice that
these are the three available 16-bit channels on the PC I/O channel. The AT-DIO-32F does not
use and cannot be configured to use the 8-bit DMA channels on the PC I/O channel.
Each DMA channel consists of two signal lines as shown in Table 2-4.
Table 2-4. DMA Channels for the AT-DIO-32F
DMA DMA DMA
Channel Acknowledge Request
5 DACK5 DRQ5
6 DACK6 DRQ6
7 DACK7 DRQ7
Two jumpers must be installed to select a DMA channel. The switch BANK A is used to select
the DMA channel for Group 1, and the switch BANK B is used to select the DMA channel for
Group 2. Figure 2-3 displays the jumper positions for selecting DMA Channels 5 and 6. In this
setting, Group 1 uses DMA Channel 5, and Group 2 uses DMA Channel 6.
BANK B
BANK A
DMA CH
7 6 5
• • • •
• •
• • • •
W1
Figure 2-3. DMA Jumper Settings for DMA Channels 5 and 6 (Factory Settings)
If you want to use only one DMA channel, then place the configuration jumpers in the positions
shown in Figure 2-4.
BANK B
BANK A
DMA CH
7 6 5
• • • •
• • • •
• • • •
W1
Figure 2-4. DMA Jumper Settings for DMA Channel 5 Only