Measurement Computing CIO-DAS16/Jr - Manual (Page 10)

CIO-DAS16/Jr User's Guide Installing the CIO-DAS16/Jr
Base address switch
The board is shipped with the base address set to 300 hex. Unless there is already a board in your system that
uses address 300 hex (768 decimal), leave the switches as they were set at the factory. In the example shown in
, the board is set for base address 300 hex (768 decimal). Figure 2
Figure 2. Base address switch
SW
A9
A8
A7
A6
A5
A4 HEX
200
100
80
40
20
10
9 8 7 6 5 4
Frequency select jumper
Use the frequency select jumper to set the frequency of the source applied to the on-board pacer to either 1 MHz
(default) or 10 MHz.
The frequency select jumper is incorporated in the board design because the original DAS-16, designed in 1984,
had a 1 MHz crystal. When MetraByte redesigned the DAS-16 and added the faster 10 MHz crystal, a jumper
was provided to maintain compatibility with older software. The CIO-DAS16/Jr has a select jumper because the
DAS-16 has the jumper. Older software may require that you set the 1 MHz setting for this jumper.
Use the 10 MHz setting for any new software development to achieve better resolution setting pacer
frequencies.
M z H
1 1
J2
0
Figure 3. Frequency select jumper
Analog channel number select switch
Use the analog input mode-select switch to configure the board for eight differential (default) or
16 single-ended inputs. Using differential inputs allows up to 10 volts of common mode (ground loop) rejection.
16 8
Figure 4. Analog channel number select switch
DMA level select switch
Use the direct memory access (DMA) level-select switch to set the DMA level to either 1 (default) or level 3.
Unless you have another board in your system using DMA level 1, leave the DMA level-select switch at the
level 1 position (
). Figure 5
Figure 5. DMA level select switch
Some network boards use DMA, and so do some IEEE-488 interface boards. If you suspect a conflict with
another board in the system, change this switch to DMA level 3.
3 1
10