Square Waveform

Generates a waveform containing a square wave. Details

offset is the DC offset of the signal. The default is 0.0.
reset signal resets the phase to the phase control value and the timestamp to zero. The default is FALSE.
frequency is the frequency of the waveform in units of Hertz. The default is 10.
amplitude is the amplitude of the waveform. The amplitude is also the peak voltage. The default is 1.0.
phase is the initial phase, in degrees, of the waveform. The default is 0.
error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurs before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.
status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
code is the error or warning code. The default is 0. If status is TRUE, code is a non-zero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
sampling info contains sampling information.
Fs is the sampling rate in samples per second. The default is 1000.
#s is the number of samples in waveform. The default is 1000.
duty cycle is the percentage of time a square wave remains high versus low over one period.
signal out is the generated waveform.
error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out indicator on the front panel and select Explain Error from the shortcut menu for more information about the error.
status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
code is the error or warning code. If status is TRUE, code is a non-zero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Square Waveform Details

If Square Wave is represented by the sequence Y, the VI generates the pattern according to the following formula:

y[i] = amp × square(phase[i]), for i = 0, 1, 2, ..., n-1,

where amp = amplitude, n = number of samples (#s), and square[p] is:

1.0 if 0 <= pmod < (0.01 × duty) × 360.0

or

-1.0 if (0.01 × duty) × 360.0 <= pmod < 360.0

where pmod = p modulo 360.0, duty = duty cycle in percent, and phase[i] is:

initial_phase + frequency × 360.0 × i/Fs

where initial_phase = phase if reset signal is TRUE, or last output phase if reset signal is FALSE.

This VI is reentrant so that it can be used to simulate a continuous acquisition from a square wave function generator. If the input control reset phase is FALSE, subsequent calls to this VI produce the output Square Wave waveform containing the NEXT n samples of a square wave. This VI remembers the phase and time stamp of the current waveform, and uses this to continuously generate and time stamp the subsequent waveforms, as long as the reset signal input is FALSE.