Documentation

Measurement Computing PCI-DIO24H Digital Output

PCI-DIO24H Digital Output

Library

Simulink® Real-Time™ Library for Measurement Computing™

Note

The PCI-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 output driver block, the port is configured as output.

Scaling Input to Output

I/O Module Output

Block Input Data Type

Scaling

TTL

Double

< 0.5 = TTL low
≥ 0.5 = TTL high

Block Parameters

Channel vector

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

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

[1,2,3,4,5,6,7,8] 

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

Port

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.

Reset vector

The reset vector controls the behavior of the channel at model termination. Enter a scalar or a vector that is the same length as the channel vector. If you specify a scalar value, that setting is replicated over the channel vector. If you specify a value of 1, the corresponding channel is reset to the value specified in the initial value vector. If you specify a value of 0, the channel remains at the last value attained while the model was running.

Initial value vector

The initial value vector contains the initial values (0 or 1) of the output channels. Enter a scalar or a vector that is the same length as the channel vector. If you enter a scalar, that value is replicated as the initial value over the channel vector. The channels are set to these initial values between the time the model is downloaded and the time it is started.

Sample time

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

PCI slot (-1:autosearch)

If only one board of this type is in the target computer, enter -1 to locate the board.

If two or more boards of this type are in the target computer, enter the bus number and the PCI slot number of the board associated with this driver block. Use the format [BusNumber,SlotNumber].

To determine the bus number and the PCI slot number, type:

tg = slrt;
getPCIInfo(tg, 'installed')

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