Re: Aw: [stella] Question about HMOVE at cycle 71

Subject: Re: Aw: [stella] Question about HMOVE at cycle 71
From: "Dennis Debro" <dennis@xxxxxxxxxxxxxxx>
Date: Thu, 14 Jul 2005 09:20:38 -0400
Hi Manuel,

> Uhm... the second HMOVE was also on cycle 74?

Yes, starting @ 71 and ending @74.

> Please notice that all HMPX values are shifted 8 pixels when doing HMOVE
> @74, so when the HMCLR writes a zero "0" to the movement registers, it's
> actually saying "shift 8 pixels to the left". To effectively "clear" the
> motion registers for that trick, you'll have to individually load all
> affected HMXX with $80...
> (Either that, or *don't* HMOVE until it's really required again...)

After I hit send I went back and re-read the timing table and saw my
mistake. I'm doing just as you suggested and setting HMxx to #$80 when I'm
not really moving. Right now it's easier to do this versus not hitting
HMOVE when it's not needed. I'll look at it more down the line of
development but it looks as if it will take me less bytes to set HMxx to
#$80 than it would be to bypass the HMOVE.

Take care,

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