Re: A86: VAT size


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Re: A86: VAT size




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----- Original Message -----
From: Cassady Roop <croop@oregontrail.net>
To: <assembly-86@lists.ticalc.org>
Sent: Saturday, January 22, 2000 8:18 PM
Subject: Re: A86: VAT size


> Some questions about calc resets...
>
> 1.  Since stat vars are present at first power-up and can't (normally)
> be deleted, can I trust that their positions in the VAT will not
> change?  Will they always be at the beginning, is what I'm asking I
> guess...

Yes. This is how the new chmasc works - I delete xStat & yStat. Then I
resize fStat to the size of the chmasc restorer thingie, and rename it. Then
I recreate the 3 stat vars. That way I can know that the restorer thingie is
always in the same spot.

> 2.  What other than a wipe of the VAT, does a mem reset do? (if
> anything?)

Actually it doesn't even wipe the VAT. Basically, it wipes page 0.

> 3.  If I were to change the _p_ptemp and _ptemp_end pointers to their
> default first power-up values, would the calc think the memory had been
> wiped?  This is why I need an answer to number 1;  'cause I would like
> the calc to think it has been mem wiped, but I want to make sure the
> default vars are there.

Not sure what you mean here. However, it's dangerous to tinker with those
pointers unless you save the VAT in a temp var, and then if they make
changes after you save the VAT in the temp var, it gets ugly... chmasc
handles this by creating invisible VAT padding (a bunch of variables called
@BUFFER1, @BUFFER2, @BUFFER3, etc)

>
> If any of that makes sense...
>
> Cassady Roop
>
>
>
> rabidcow@juno.com wrote:
> >
> > normal vars should be from $bfff to (_P_PTEMP+1)
> > temp vars (var name starts with '$') should be from (_PTEMP_END+1) to
> > (_P_PTEMP+1)
> >
> > _P_PTEMP = $d297
> > _PTEMP_END = $d29a
> >
> > the +1 is because they're 24 bit pointers, but they're always on page 7
>



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