Re: [CAD_CAM_EDM_DRO] Re: Laser mouse based DRO - Stand Alone ?

Alan Marconett wrote:

>Hi Art,
>
>I fully agree! And I've ran the DRO chips on an old PC myself! OK, I
>didn't have encoders on the axis of a machine, but I ran the encoders!
>
>PICs are a LOT of fun! They are simple enough that you can get around the
>whole job. Learn a little C, learn a little micro processor an electronics,
>a really good project for learning. And they can be quite powerful
>solutions for commercial products as well (my new job).
>
>Hi-Tech has a FREE "lite" compiler for a few selected PICs. So do some
>other compiler suppliers.
>
> http://www.htsoft.com/
>
>CCS is another compiler; cheaper, probably affordable for many hobbyists
>(Hi-Tech is pricy).
>
>Alan KM6VV
>
>

Art,

Not really CNC-related (except for the fact that you can generate step
pulses or make DROs with a microcontroller), but here's my two cents.

Unless you're required to use a PIC (ie, the chip is already a part of
the design, and the customer won't change it), try the AVR from Atmel.
The cost of the chip is similar (AVRs used to be more expensive, but now
they're less than a PIC in many instances), but I find the instruction
set to be *much* better. There are little things, like the fact that
the PIC has no add-with-carry instruction, to big things like the AVR
having 32 registers. The AVR also has a bunch of C compilers available,
like the PIC.

One hardware advantage to the AVR is that in-circuit programming only
requires a 5V supply (some even program at 3V, I think), whereas the PIC
needs a 12V line to get into programming mode. The PIC has an advantage
in that it only takes 5 wires, and the AVR needs 6 (both including power
and ground).

Either one can be used for some fun projects, and the flexibility of
these chips is pretty amazing.
Just an opinion from someone who's been writing microcontroller code for
the last 15 years or so :)

- Steve