[chbot] Mouse Scroll Wheel Question

[Richard Jones]

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A friend of mine wishes to use a mouse scroll wheel circuit as a low cost
USB input for a software defined radio, removing the scroll wheel and
providing his own pulses from a rather nice 'knob'.
Has anyone actually had a mouse apart apart and figured it out?
The initial assumption was that the wheel would have an optical quadrature
detector but there seems to be only one optical detector, and I suspect
that the inputs are multiplexed from buttons etc.
Any ideas welcome.

Richard Jones