Martin McCormick wrote:
>         Now, for my PIC question.  Are any of the following so
> obsolete that, if I built something with them, I couldn't replace it
> with what's current without a total re-write of the program?
>
> 16C54 12c509JW 16F84 16C71JW 16c64jw 17C42

You sure know how to pick'em!  This is quite a lineup of museum pieces and
outright losers.  However, PIC code is quite portable between chips in the
same family, and even reasonably portable accross families, especially if
you use some discipline up front.

My advice if you're just starting now is to get a few 18F252 and don't
look back.  Except for wider choice of packages, the older chips are
pointless in low volume designs.  With the fixed 18F1320 there will soon
be an 18 pin package in the 18 family.  If you really need a smaller
package, then look at the 16F630, 12F629, and 12F675.  These are all
actually 16 family parts despite their name.  There is absolutely no
reason to mess with 12-bit core parts for low volume designs.

Hopefully we can start recommending the dsPICs soon.


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