Re: [stella] behold, i am become shiva, destroyer of kernals!

Subject: Re: [stella] behold, i am become shiva, destroyer of kernals!
From: Christopher Tumber <christophertumber@xxxxxxxxxx>
Date: Fri, 12 Mar 2004 11:48:12 -0500
Okay, enough Black Helicopter stuff, this is the REAL explanation. And this time I can prove it.


PLP'ing an unknown value can result in munging the D flag.

The skipdraw routines rely on SBC commands. So do other routines, and there were other problems for example the ball leaving the screen and never coming back.

Having the D flag set will cause very different results in these operations.


Sure enough, if I add a SED command just before the fixed missile skipdraw, the problem reappers.


This is a problem on the Supercharger but not elsewhere because:

PLP ;(ENAM1)

Results in a different value than in the emulators (or Cuttle Cart 2 apparently). So the D flag does not get set in the emus/CC2 but does on the Supercharger.



Chris...

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