Re: [CAD_CAM_EDM_DRO] Basic Stamp + Encoder

Hi Dave,

I'll have a good look in my system and send you all that I have on this
subject tomorrow, it is late here.

I am working on just such a system and am quite close to finishing the
design. It would be wise to download the data sheets of the PIC's you are
thinking of using. You are quite correct, the history, conditional code or a
table are not necessary because the encoders are read via interrupts. No
transitions can be lost this way. It is very possible to read four encoders
and display the results and still have some spare time on a PIC running at
20 meg.

Regards,

Terry



| Hi Terry,
|
| I have not done any PIC programming but have worked for large computer
| manufacturers (CDC and now Cray) for years and have been programming in
all
| languages since about 1968. I think programming for a PIC would be a nice
| change of pace!
|
| I need a DRO for my Bridgeport and plan to make one eventually using a PIC
| to do the counting and drive the display. I have looked at the code for
the
| PC based DRO systems and see that it keeps a history of the last few
encoder
| transitions - I think this is an attempt to avoid missing transitions. The
| way it is done uses either a lot of conditional code (which will slow the
| program down) or a large table (which will not fit in a PIC memory). I
don't
| think this history is really necessary.
|
| I would like to see the code you have for PICs. It will give me another
| example to study and hopefully convince me that the history stuff is not
| necessary.
|
| Regards,