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NNTP-Posting-Date: Sat, 03 Mar 2012 13:10:13 -0600
Date: Sat, 03 Mar 2012 14:10:13 -0500
From: Steven Hirsch <snhirsch@gmail.com>
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Subject: Re: Best place to hide about 30 bytes in //e RAM
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On 03/03/2012 10:41 AM, Egan Ford wrote:
> Programmers,
>
> I just created a program launcher that I'd like re-activate on CTRL-RESET. I
> know that I have no control over the programs being launched and that there
> will be a chance that my reset vector bytes ($3F2-$3F4) may get hosed, but in
> the event they do not, where is the least likely place someone will use
> memory? I tried page $BF with the worse results. Right now I am starting at
> $310 with good results, but I'd like better results if possible.

How about the beginning of the stack page?  IIRC, few (if any) programs get 
that close to the end.  I hacked up a modified version of the RamFast ROM that 
copied a small software loop into that location to speed things up when 
running with ZipChip or TransWarp 2e accelerators (where DMA is a 
non-starter).  Never saw a problem with stack collisions.