Re: PIC based DRO

> From: "james owens" <wotisname@...>
>
> I have been considering this very issue for some time. We have an electronics magazine here that is PIC crazy, every project that appears uses a PIC some where.

Sounds like Circuit Cellar or Midnight Engineering, both good magazines
for our type of stuff.

> Both have problems, especially below .001"/count. With linear strips, a
> person is relying pretty heavily on the linearity of the ballscrews in
> the photoplotter that created them in the first place.

I've used look up tables in the past to correct for non-linear stages,
however the tables are pretty large and I doubt it would fit in a PIC.
If you really need the accuracy vs. needing repeatability, you might
need the more expensive glass doodads. For some applications
repeatability combined with traditional measurement tools might be
enough.

Jim Eckman

P.S. On accepting free advice, why would anyone read a news list not
believe in using free advice? Sounds like a waste of time otherwise. Of
course anyone who wants to pay for embedded systems work can pay my low
hourly rate of $125 ;)