NAME

       siggen - signal generator

SYNOPSIS

       loadrt siggen [num_chan=num | names=name1[,name2...]]

DESCRIPTION

       siggen  is  a  signal  generator  that  can  be  used for testing and other applications that need simple
       waveforms.  It produces sine, cosine,  triangle,  sawtooth,  and  square  waves  of  variable  frequency,
       amplitude, and offset, which can be used as inputs to other HAL components.

       siggen  supports  a  maximum  of  sixteen channels.  The number of channels actually loaded is set by the
       num_chan argument when the module is loaded.  Alternatively, specify names= and unique names separated by
       commas.

       The num_chan= and names= specifiers  are  mutually  exclusive.   If  neither  num_chan=  nor  names=  are
       specified, the default value is one.

NAMING

       The names for pins, parameters, and functions are prefixed as:
         siggen.N. for N=0,1,...,num-1 when using num_chan=num
         nameN. for nameN=name1,name2,... when using names=name1,name2,...

       The siggen.N. format is shown in the following descriptions.

FUNCTIONS

       siggen.N.update (uses floating-point)
              Updates  output  pins  for signal generator N.  Each time it is called it calculates a new sample.
              It should be called many times faster than the desired signal frequency, to avoid  distortion  and
              aliasing.

PINS

       siggen.N.frequency float in
              The output frequency for signal generator N, in Hertz.  The default value is 1.0 Hertz.

       siggen.N.amplitude float in
              The  output  amplitude  for  signal  generator  N.  If offset is zero, the outputs will swing from
              -amplitude to +amplitude.  The default value is 1.00.

       siggen.N.offset float in
              The output offset for signal generator N.  This value is added directly to the output signal.  The
              default value is zero.

       siggen.N.reset bit in
              Resets output pins to pretermined states:
                sine      0
                sawtooth  0
                square   -1 * amplitude
                cosine   -1 * amplitude
                triangle -1 * amplitude

       siggen.N.clock bit out
              The clock output.  Bit type clock signal output at the commanded frequency.

       siggen.N.square float out
              The square wave output.  Positive while triangle and cosine are ramping upwards, and while sine is
              negative.

       siggen.N.sine float out
              The sine output.  Lags cosine by 90 degrees.

       siggen.N.cosine float out
              The cosine output.  Leads sine by 90 degrees.

       siggen.N.triangle float out
              The triangle wave output.  Ramps up while square is positive, and down while square  is  negative.
              Reaches its positive and negative peaks at the same time as cosine.

       siggen.N.sawtooth float out
              The  sawtooth  output.   Ramps  upwards to its positive peak, then instantly drops to its negative
              peak and starts ramping again.  The drop occurs when triangle and cosine  are  at  their  positive
              peaks, and coincides with the falling edge of square.

PARAMETERS

       None

LinuxCNC Documentation                             2007-01-16                                          SIGGEN(9)