Re: [stella] Syncing without WSYNC

Subject: Re: [stella] Syncing without WSYNC
From: Chris Wilkson <ecwilkso@xxxxxxx>
Date: Thu, 30 Aug 2001 11:04:55 -0400 (EDT)
On Thu, 30 Aug 2001, B. Watson wrote:

> Does anyone know, is one scanline *exactly* 76 cycles? I.E. if I write a
> scanline loop with no STA WSYNC in it, that takes exactly 76 cycles (with
> dey;bne start_of_loop as the last 5 cycles), will the Atari stay in sync
> with the TV picture, or are the WSYNCs absolutely necessary? The emulators
> all handle it fine, but will a real Atari be able to do this?

Yes, you can do this.  Strobing the WSYNC register is just a lazy way to do
it.  It also only takes 2 bytes.  Delay loops and whatnot waste valuable ROM
space.  :)


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