Configuration and Installation Chapter 2
PC-DIO-24 User Manual 2-2 © National Instruments Corporation
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INSTRUMENTS
1U2
2W1
3F1
4W2
Figure 2-1. 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 U2 (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 U2 corresponds to one of the address lines A9 through A2. Thus, 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