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COUNTER

NAME
SYNOPSIS
DESCRIPTION
FUNCTIONS
PINS
PARAMETERS
SEE ALSO

NAME

counter − counts input pulses (DEPRECATED)

SYNOPSIS

loadrt counter [num_chan=N]

DESCRIPTION

counter is a deprecated HAL component and will be removed in a future release. Use the encoder component with encoder.X.counter-mode set to TRUE.

counter is a HAL component that provides software- based counting that is useful for spindle position sensing and maybe other things. Instead of using a real encoder that outputs quadrature, some lathes have a sensor that generates a simple pulse stream as the spindle turns and an index pulse once per revolution. This component simply counts up when a "count" pulse (phase-A) is received, and if reset is enabled, resets when the "index" (phase-Z) pulse is received.

This is of course only useful for a unidirectional spindle, as it is not possible to sense the direction of rotation.

counter conforms to the "canonical encoder" interface described in the HAL manual.

FUNCTIONS

counter.capture-position (uses floating-point)

Updates the counts, position and velocity outputs based on internal counters.

counter.update-counters

Samples the phase-A and phase-Z inputs and updates internal counters.

PINS

counter.N.phase-A bit in

The primary input signal. The internal counter is incremented on each rising edge.

counter.N.phase-Z bit in

The index input signal. When the index-enable pin is TRUE and a rising edge on phase-Z is seen, index-enable is set to FALSE and the internal counter is reset to zero.

counter.N.index-enable bit io

counter.N.reset bit io

counter.N.counts signed out

counter.N.position float out

counter.N.velocity float out

These pins function according to the canonical digital encoder interface.

PARAMETERS

counter.N.position-scale float rw

This parameter functions according to the canonical digital encoder interface.

counter.N.rawcounts signed ro

The internal counts value, updated from update-counters and reflected in the output pins at the next call to capture-position.

SEE ALSO

encoder(9). The HAL User Manual.