RE: [stella] DD Build 0002

Subject: RE: [stella] DD Build 0002
From: "Brian Prescott" <bprescot@xxxxxxxxxxxxxxx>
Date: Sat, 22 Sep 2001 10:21:44 -0400


Another thing that I have found in my 2600 programming trials and
tribulations was that the best place for a problem to hang out is in clear
sight.  You need to use:

	LDA #PF_Reflect

The emulator just happened to work because the right bits were in memory
location 1.


-----Original Message-----
From: owner-stella@xxxxxxxxxxx [mailto:owner-stella@xxxxxxxxxxx]On
Behalf Of Brian Prescott
Sent: Saturday, September 22, 2001 10:02 AM
To: stella@xxxxxxxxxxx
Subject: RE: [stella] DD Build 0002


To remove the blip at the top, all I did was move the code:

	LDA #0
	STA PF2; zero out playfield

up to right under the STA VBLANK.  It must've been a remnant left in PF2
that was drawn on the bottom of the screen, but then again, I'm no expert.

I ran the binary through my Supercharger, and I have good news and bad news.
The good news is that the screen doesn't roll.  The bad news is that the
"Derb" comes out backwards on my Atari, while it comes out as expected on
z26.  I haven't a clue why that would be happening, I looked real quick at
the source code and nothing jumped out at me.

One thing that I did notice during my Vault Assault development was that I
needed to test with the actual Atari somewhat frequently, as I had some
nasty bugs work their way into it by just using the emulator only.  (By the
way, for those of you who own one of the Vault Assault carts, try playing a
game where you score exactly 600 points.  Don't bother trying it with the
binary posted on my web page, though.)


-----Original Message-----
From: owner-stella@xxxxxxxxxxx [mailto:owner-stella@xxxxxxxxxxx]On
Behalf Of Glenn Saunders
Sent: Saturday, September 22, 2001 3:34 AM
To: stella@xxxxxxxxxxx
Subject: [stella] DD Build 0002

I've got the bordering working properly but I have a weird artefact at the
top of the screen.

Could someone take a look at this and tell me why that's showing up?

Also, I adjusted the total scanlines to 200 (most TVs should show the
bottom without scrolling off).  I want to maximize the active playfield
area.  Could someone check to make sure it's not generating too many total
scanlines (including overscan) per screen?   It doesn't roll for me but I
want to keep it by the book.


Glenn Saunders - Producer - Cyberpunks Entertainment
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