Jinx wrote...

>I have experience with a few types too - 68705, 1802, 6510,
>2313, 2051 and 8031.=20

>Isn't it just great when you've got 16k
>of space in front of you and you can do pretty much what the
>heck you want to in terms of long jumps, reading program
>memory from any address, play with the stack etc etc and
>not have to worry about page wrap-arounds or looking for
>registers ?=20

Ah, yes: the stack.  After almost two years fiddling with PICs, I'd
almost forgotten what a "stack" was.

When I first started with these little critters, I was all set to do the
usual stack stuff: passing parameters, setting aside space for temporary
storage within a subroutine, etc.  I looked and looked for
stack-manipulation instructions, didn't find any.  Then it dawned on me:
no stack.  Jeez.

That was a bad day.

>Seriously, I'm wondering how PICs ended up this
>way, so very different from any other micro. Anyone know ?

I'm not 100% sure of this, but I think PICs started out as peripheral
controller chips to complement General Instrument's CP1600.  They were
cheap, simple, and blazingly fast.

Over time, they've grown up.  Still darned fast, though.

Cheers,

Dave

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