On 19 Sep 97 at 11:46, Clyde Smith-Stubbs wrote:

> On Thu, Sep 18, 1997 at 07:50:09PM -0500, John Payson wrote:
>
> > It's true that not all PICs have a hardware known-zero.  Nonetheless, you
> > might want to consider having the compiler allocate one.  You could use
>
> The trouble with allocating a RAM location as a zero is that you
> have to ensure it is in fact always zero (some of your suggestions
> make it non zero temporarily) or be prepared to save and restore it
> on interrupts.

If it's a hardware KZ, I presume you mean it can't be set Non-Z?
If this is so, how could John Payson's dec loop work, since you
couldn't set it up.

>
> An easier approach is to use a known-zero location on chips that
> have it, and do things other ways on other chips. This is already on
> our to-do list (thanks to your earlier suggestions!)

What are some example KZ's?
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)