hil_write_pwm_buffer :: QUARC MATLAB Functions

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hil_write_pwm_buffer

Deprecated

The HIL API MATLAB functions have been deprecated in favour of the new quanser.hardware.hil class, which has support for code generation for Quanser targets. Hence, with the new hil class it is possible to run MATLAB scripts in real-time on Quanser targets, while making use of the Quanser hardware.

Writes the specified samples to the pwm channels at the indicated sampling rate.

Syntax

[samples_written, err] = hil_write_pwm_buffer(board, clock, frequency, channels, duty_cycles)

Description

Writes the specified samples to the pwm channels at the indicated sampling rate. The number of samples is determined by the number of columns in the duty_cycles matrix.

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 handle returned by hil_open.

clock

The clock to use as a timebase for the buffered operation. Hardware clocks are numbered incrementally starting at 0, with 0 meaning HARDWARE_CLOCK_0, 1 meaning HARDWARE_CLOCK_1, etc. The number of clocks available depends on the board selected. Refer to Clocks for more information.

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

frequency

The sampling frequency in Hertz at which samples will be collected.

channels

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

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

duty_cycles

A matrix of pwm duty cycles. Values must lie in the range -1.0 to +1.0. There must be one row for each channel and one column for each sample.

Outputs

samples_written

The number of samples written. This value will equal the number of samples specified unless the operation was canceled.

err

A negative error code or zero on success.

Examples

% Uniformly distributed random duty cycles between -1 and +1.
duty = (rand(2, 5000)-0.5)*2;

% Writes 5000 samples to pwm channels 0 and 3 at 1 kHz using SYSTEM_CLOCK_1
hil_write_pwm_buffer(board, -1, 1000, [0 3], duty);