> resolution

The resolution can be pretty good. A normal mouse has 24 to 48 slots
(varies) and a mechanical multiplication ratio of x 10 or so. The real
resolution is near 100 dpi with the original ball & axle. If you drive the
axle directly you just count the slots and arrange for one rotation to
satisfy your resolution requirements. All quadrature encoders resolve 2 x
the number of slots. Therefore 30 slots = 60 distinctly discernible axle
positions.

Several people have used mice in DIY CNC machinery. Some have used them as
is (like me), connected to a PC serial port.

Peter

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