Re: [stella] kernal klunk

Subject: Re: [stella] kernal klunk
From: Dennis Debro <ddebro@xxxxxxxxxxxxx>
Date: Mon, 9 Feb 2004 9:03:04 -0500
Hi Kirk,

Hopefully this will sort in the archives correctly. This isn't a true reply as the message isn't in my inbox anymore.

> So I'm having trouble with my kernal...but I can't understand why I'm seeing
> it *now*, everything I've been changing is in VBLANK (the fractional
> positioning, and I just added in a routine to rebound off the floor at 1/2
> the descending speed) and the Kernal, which seemed pretty solid before, 
> should be unaffected.

It seems the problem is your kernel loop is taking longer than you expected. Counting the cycles at the maximum cycle count shows the last branch happening at cycle 73. The loop branch crosses a page boundary so that's 4 cycles vs. 3. Doing this produces an extra scan when all your objects are on the same scan line.

Take care,

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