Measurement Computing CIO-DIO24H Digital Input

CIO-DIO24H Digital Input (not recommended)


Simulink® Real-Time™ Library of Drivers No Longer Recommended for Use


The CIO-DIO24H has one 8255 chip with 3 ports (A,B,C). Each port has a maximum of 8 digital I/O lines that can be configured as inputs or outputs.

Use a separate driver block for each port. By selecting the digital input driver block, the port is configured as input.

Scaling Input to Output

I/O Module Input

Block Output Data Type




TTL low = 0.0
TTL high = 1.0

Block Parameters

Channel vector

Enter numbers between 1 and 8 to select the digital input lines used with this port. This driver allows the selection of individual digital input lines in arbitrary order. The number of elements defines the number of digital lines used.

For example, to use all of the digital inputs for one port, enter


Number the lines beginning with 1 even if this board manufacturer starts numbering the lines with 0.


From the list choose either A, B, or C. The I/O board has an 8255 chip with 3 ports. The Port parameter defines which port of the 8255 chip is used for this driver block. Each port has a maximum or 8 digital lines that can be configured as inputs or outputs depending on which driver block is chosen. In each case, one block is required for each port.

Sample time

Enter the base sample time or a multiple of the base sample time (-1 means sample time is inherited).

Base address

Enter the base address of the board. This entry must correspond to the DIP switch setting on the board. For example, if the DIP switch setting is 300 (hexadecimal), enter 0x300.

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