Strangely, my posts are not going through... So i'll try again. Forgive me
if this actually goes up twice.
I'm currently experimenting some dirty tricks in order to save space. If
the 9-byte VSYNC is giving trouble, you might be able to use this. Under
certain conditions (stack pointer = $FF, that is) you can do VSYNC in 8
bytes, provided you combine it with the overscan timer.
.1
LDX INTIM ; overscan timer
BNE .1
; x=0, Z flag = 0 here
; If stack pointer isn't initially $FF, this won't work!
TXS ; set stack pointer on top of VSYNC register ($00)
PHP ; pushes Z=1 (bit 1 set) to VSYNC then resets SP to $FF.
INC WSYNC ; INC does two writes to WSYNC, giving you two scanlines!
STA WSYNC
STX VSYNC ; x=0, ends VSYNC
I haven't actually tried this on real hardware, so use at your own risk!
>From: "Aaron" <stella-receiver@xxxxxxxxxxxxxxxxx>
>Reply-To: stella@xxxxxxxxxxxxxxxxxx
>To: stella@xxxxxxxxxxxxxxxxxx
>Subject: RE: [stella] Another kernel is rolling
>Date: Thu, 7 Apr 2005 01:27:48 -0400
>
>Dennis Debro said:
> > I ran 2 versions on my 7800 via CC2, one with the old VSYNC routine and
> > another with Edwin's routine. The title screen synced fine with the old
> > VSYNC routine. When I used the one from Edwin, that's presently in the
> > macro.h file, the title screen didn't sync properly.
>
>Well, assuming that's actually the problem, I think it's sufficiently
>weird that I can't be mad about not finding it.
>
>Thanks Dennis!
>
>Archives (includes files) at http://www.biglist.com/lists/stella/archives/
>Unsub & more at http://stella.biglist.com
>
Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://stella.biglist.com
