Re: mouse encoder

At 00:03 23/08/2001 +0000, you wrote:

>Thanks for the details. I have one of Dan's tachs, but found the
>reflective sensor to be a problem in my environment (only limited
>testing). I hadn't thought of using slotted IR sensor, I have some,
>might give it a try. You say you need a different version of
>interface? Or that you can accommodate both? I'll have to give it a
>try.

The counting circuit basically handles anything that can give it a TTL
signal. The two sensors I use need different pull-up resistors for the
photosensor, and different series resistors for the IR emitting diode;
otherwise, both are compatible with the meter.

A problem I have found with the reflective type is that they are (not
surprisingly) sensitive to the IR reflectivity of the surface you point
them at. I have taken to using alternating matt black & white paint
stripes, rather than relying on polished metal to reflect IR, since
discovering that the aluminium pulleys on my Myford seem to be IR absorbent
even when polished.

>Be sure and post the magazine's publication date, although I suspect it
>will be difficult to get single copies!

Will do.

>Which PIC did you say you used? Sold separately? And did you program
>in assembly or 'C'? (BASIC?).

It is a 16F84. Haven't worked out the marketing detail yet - will advise in
due course.

The coding is all in "C", bar about a dozen words of assembler for the
interrupt routine.

>Hope you do well on the kit sales.

Thanks - so do I!

Regards,
Tony