RE: [stella] 262 scanline kernel is rolling

Subject: RE: [stella] 262 scanline kernel is rolling
From: "Dennis Debro" <dennis@xxxxxxxxxxxxxxx>
Date: Sat, 26 Mar 2005 14:49:35 -0500
Hi there,

> Right now you're writing 0 at the start of vertical blank
> and 8 at the start of overscan.

That is strange. As Thomas said, D1 of VBLANK only controls the TIA output.
At least as documented by the programming manual. So writing 8 to the
register is essentially the same as writing 0 (i.e. enabling TIA output).

I don't have my hardware setup at the moment to play with this. Was this
truly the problem? What happens if you used other values or ignored VBLANK
altogether? By the values you were entering this should have been simulated.
Are there other bits used by VBLANK that we don't know about?

Take care,

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