Re: [stella] The mother of all bankswitching trickery :-)

Subject: Re: [stella] The mother of all bankswitching trickery :-)
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Sun, 8 Dec 2002 13:22:22 +0100
> I wrote:
> >1. The log is wrong!
> >2. The 6507 has only 12 address lines
> >
> >-> The jump goes to $xc96. 
> >
> >Or $fc96 if you should prefer that... ;-)
> 
> ...or maybe not???

You are almost correct. The z26 log shows the programm counter,
which still is 16 bit even in the 6507. But since only 13 address
lines are connected externally, the three high bits aren't evaluated.
So $bc96 is the same as $fc96 to the VCS. Therefore the jump goes
to address $0c96 in the bank that is currently mapped in.


Ciao, Eckhard Stolberg


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