quanser.hardware.hil.read_digital :: QUARC MATLAB Functions

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quanser.hardware.hil.read_digital

Reads the specified digital channels.

Syntax

[values, err] = board.read_digital(channels)

Description

Reads the specified digital channels immediately. It returns vector of logical values where true (1) represents a high digital input, and false (0) represents a low digital input.

Warning Many cards allow the digital I/O lines to be programmed as inputs or outputs. The digital I/O lines are configured as inputs or outputs using the set_digital_directions function. All the channels which will be used as digital inputs must be configured as inputs using this function. Failure to configure the digital I/O may result in the read_digital function failing to read those inputs.

If no err output is provided then it throws an exception if an error occurs. In generated code it prints the error message. Use hil_get_error_message to get the message associated with an error code.

Parameters

board

The board instance returned by the quanser.hardware.hil.open function.

channels

A vector of channel numbers. Channel numbers are zero-based.

Select a board type from the list for board-specific details: .

Outputs

values

A vector of digital values, as int8s. There is one element for each channel.

err

A negative error code or zero on success.

Examples

% Reads digital channels 0, 3 and 5
values = board.read_digital([0 3 5]);