NAME

       sim_encoder - simulated quadrature encoder

SYNOPSIS

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

DESCRIPTION

       sim_encoder  can  generate quadrature signals as if from an encoder.  It also generates an
       index pulse once per revolution.  It is mostly used for testing and simulation, to replace
       hardware  that  may  not  be  available.   It  has  a limited maximum frequency, as do all
       software based pulse generators.

       sim_encoder supports a maximum of eight 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.

FUNCTIONS

       sim-encoder.make-pulses (no floating-point)
              Generates  the actual quadrature and index pulses.  Must be called as frequently as
              possible, to maximize the count rate and minimize jitter.  Operates on all channels
              at once.

       sim-encoder.update-speed (uses floating-point)
              Reads the speed command and other parameters and converts the data into a form that
              can be used by make-pulses.  Changes take effect only when update-speed runs.   Can
              (and  should) be called less frequently than make-pulses.  Operates on all channels
              at once.

NAMING

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

       The sim-encoder.N. format is shown in the following descriptions.

PINS

       sim-encoder.N.phase-A bit out
              One of the quadrature outputs.

       sim-encoder.N.phase-B bit out
              The other quadrature output.

       sim-encoder.N.phase-Z bit out
              The index pulse.

       sim-encoder.N.speed float in
              The desired speed of the encoder, in user units per per second.  This is divided by
              scale, and the result is used as the encoder speed in revolutions per second.

PARAMETERS

       sim-encoder.N.ppr u32 rw
              The  pulses per revolution of the simulated encoder.  Note that this is pulses, not
              counts, per revolution (ppr).  Each pulse or cycle from the encoder results in four
              counts, because every edge is counted.  Default value is 100 ppr, or 400 counts per
              revolution.

       sim-encoder.N.scale float rw
              Scale factor for the speed input.  The speed value is divided by scale to  get  the
              actual  encoder  speed  in revolutions per second.  For example, if scale is set to
              60, then speed is in revolutions  per  minute  (RPM)  instead  of  revolutions  per
              second.  The default value is 1.00.