Measurement Computing CIO-DI48 - Manual (Page 6)

3.0 HARDWARE SETUP
3.1 BASE ADDRESS SELECTION
The CIO-DI## employs the PC bus for power, communications and data transfer. As
such it draws power from the PC, monitors the address lines and control signals and
responds to it's I/O address, and it receives and places data on the 8 data lines.
The BASE address is the most important user-selectable feature of the CIO-DI##.
The base address, an d offsets from it, are the locations that PC software reads input
data from.
Base address dip switches are used for setting the base address. Each switch position
corresponds to one of the PC bus address lines. Placing a switch down puts it in the
active position.
A complete address is constructed by adding the HEX o r decimal number which
corresponds to all the address bits the CIO-DI## has been instructed to respond to.
For example shown in Figure 3-1, switches 9 and 8 are DOWN, al l others UP.
Address 9 = 200h (512D) and address 8 = 100h
(256D), When added together they equal 300h (768D).
NOTE
Disregard the numbers printed on the switch; refer only to the
numbers printed in white on the board!
In Figure 3-1, note that the number of switches varies with the board version.
Certain addresses are used by the PC, others are free and may be used by the
CIO-DI## and other expansion boards. We recommend trying the factory default
address 300h (768D) first.
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