The usual issue with many of those encoders is they can be one of
several codes and the rate in pulses per revolution is much higher
than the encoder used. The difference is in the range of less than
90 per revolution to some of the Bornes at 400pulses revoution.
The latter encoders at 200P/R and higher need a much more responsive
program usually interrupt driven. if not it just does flaky things. If
your doing your own code that is generally not an issue, For QCX you
can't (sources not available). For someone else design the pins
needed (for interrupt interface) may already be claimed. That
makes coding awkward.
A optical version of the typical QCX and similar encoder is
common and cheap buy spares. Simply dropping something
else in without code work is not often successful.
Please reply on list so we can share.
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