Re: LZ-Adv: Interrupt-without graph mem???
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> > I downloaded GameWizard 0.9 by Jimmy Mardell (mja@algonet.se) off
> > ticalc.org a few days ago. It uses an interrupt system to activate a
> > menu when you hold <on> and press <enter>. This can be activated in a
> > ZShell program or even outside of ZShell. When it is activated you can
> > pull up the menu even when you are on the graph screen. I thought that
> > interrupts used addr. 8888h (which is in the graph mem) to store the
> > interrupt routine that they want to use (as in greyscale). How is it
> > possible to change the graph mem, but not mess up the interrupt??? Does
> > it have something to do with a VBL interrupt? Is that why you have to
> > hold <on> for it to work? How does this work and how could I use it to
> > say...activate a small asm program?
>
> The interrupt array (the one with 257 identical bytes) is stored right
> AFTER zshell. The trick is that you make the zshell string longer (by
> just adding spaces after it in basic mode). If you make it about 600 bytes
> longer, you can store then interrupt table at $9100-$9200 and the interrupt
> routine at $9292. Then there are some holes where you can store variables
> that the interrupt program uses.
Did you just change the bytes after the ZShell string or did you have to
change parts of the actual ZShell string itself?
>
> Of course you can't run two programs with the this method at the same time...
>
> The idea with patching ZShell is Mike Bakers. The problem is that those
> programs won't work when the next ZShell version comes out, since that
> zshell is probably a bit bigger.
did you use this method just so that you could have access to the graph
mem w/o screwing things up?
Thanks this helps a lot!
<pre>
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Thayne Miller
yomaster@geocities.com
YoMaster's Domain:
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</pre>
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