Base i/o address settings, Figure d-1. pcdio24 parts locator diagram, Figure d-1 – National Instruments PC-DIO-24/PnP User Manual
Page 86
Appendix D
Using Your PC-DIO-24 (Non-PnP) Board
© National Instruments Corporation
D-3
PC-DIO-24/PnP User Manual
Figure D-1. PC-DIO-24 Parts Locator Diagram
Base I/O Address Settings
The base I/O address for the PC-DIO-24 is determined by the switches
at position U9 (see Figure 2-1). The switches are set at the factory for
the I/O address hex 210. With this default setting, the PC-DIO-24 uses
the I/O address space hex 210 through 213.
Note:
Verify that this space is not already used by other equipment installed in
your computer. If any equipment in your computer uses this I/O address
space, you must change the base I/O address for the PC-DIO-24 or for the
other device.
Each switch in U9 corresponds to one of the address lines A9
through A2. For space reasons, not all address lines are separately
labeled on the board. The range for possible base I/O address settings is
hex 000 through 3FC. Base I/O address values hex 000 through 0FF are
reserved for system use. Base I/O values hex 100 through 3FF are
available on the I/O channel. A1 and A0 are used by the PC-DIO-24 to
decode the onboard registers. On the U9 DIP switches, press the side
marked OFF to select a binary value of 1 for the corresponding address
bit. Press the other side of the switch to select a binary value of 0 for the
corresponding address bit. Figure D-2 shows two possible switch
settings.
1
W2
2
W3
3
U9
4
Product Name
3
4
1
2