On Tue, Oct 12, 2004 at 04:02:46PM -0700, Olin Lathrop wrote:
> 
> > It does beg a question from the pro side of the fence though: How do you choose
> > the right part for a particular job? Do you start with the smallest/cheapest
> > part then iterate as needed for more features? Or is it better to prototype
> > with more than you need, then pick the chip that fits the final software? Or
> > is cost the ultimate arbiter?
> 

> I usually scope out what hardware features are needed, then pick the
>cheapest PIC that has them.  I usually get samples of that PIC within its
>subfamily that has the maximum RAM and program memory.  The volume purchases
>happen later after we know how much of that is needed so a scaled down PIC
>with the same hardware can be chosen.  For example, I would develop with a
>18F252, but spec out 18F242 for production if everything fits.  >

That's lateral thinking to what I do as a hobbyist. But since it's a one off
(or maybe a two off) I just end up sticking with the bigger target.


> > And as cool as the 10F family is, it's tough for a novice (or even intermediate)
> > hobbyist to prototype with them, despite the coolness factor.
> 

> I don't think it's that hard.  It is certainly easy enough to lay out pads
> for a SOT-23 package.  I hear the 10F parts also come in 8 pin DIP versions
> for prototyping, but that makes no sense since why not just use a 12F629 in
> the first place since one off cost doesn't matter.  

Exactly! In fact for an 8 pin DIP I'd choose the 12F675 under the thinking
outlined above.


> > I keep reading on the list that the higher potential speeds, banking 
> > simplification, and rich feature set makes the 18F family a better overall
> > bet for the hobbyist. I'm just wondering if that is in fact true.
> 

> I think it is.  The extra few cents to go from a 16F876 to a 18F252 once or
> even a dozen times is probably below the noise floor for most hobbyists.  I
> was just trying to point out that there is still value in the "lesser"
> families, even to hobbyists in limited circumstances.  For 18 pins and up, I
> would advise hobbyists to stick to the 18F family.

I think I'm going to step up to the 18F plate my next go round. For most of the
small projects I've been working on I've been using the 16F88 which is the
biggest and most feature packed 18 pin 16F part. But I have some 18F1330's
I believe that I think I'll give a shot on the next go round.

BAJ
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