playsoft

Of course, please feel free to include it. However it does need cart RAM which is used to hold the 320C playfield as a bitmap (so there are Maria cycles left for sprites). If it's still viable let me know, if nothing else I'd add some audio. The sequel does require some more material from Atari to work with, but I am sure they will provide 😃

I think it would have been possible.

And it could look better with graphics specifically designed for 320C. I just did an automatic conversion of those graphics; whenever there's a conflict with a pixel pair containing 2 different colours, replace the darkest pixel with the background. The snow is just re-used starfield code but there's something unintentionally neat about how it looks when the screen transitions.

I was thinking more of gameplay but I do have a 320C mini-game of sorts; a spoof game that lampoons Atari. The idea was to release it last Christmas when the Atari acquisition of AtariAge was fresh in everyone's mind, but I ended up abandoning it as it was too stupid. It's probably not entirely suitable for kids or Atari employees. Graphics from: https://sondanielson.itch.io/gameboy-simple-rpg-tileset https://parabellum-games.itch.io/gb-studio-indoors https://parabellum-games.itch.io/gb-studio-character-pack https://opengameart.org/content/16x16-fantasy-tileset atarimas.a78

I don't know if this would be suitable but I ported Blowsub, originally a mini-game on the 5200/A8. I wouldn't normally revisit things past, but I always wondered with more time what else I may have done with it. The answer seems to be not a lot, because after rewriting it for the 7800 I haven't felt inspired to do anything with it. Graphics are by @kiwilove and Pixel fish tank set by Brysia (itch.io). Control is either a joystick in port #1 or a paddle in port #2. The aim is to destroy the submarines scoring enough points for extended time; hitting a mine will destroy everything on screen, hitting an electric eel is shocking. It lacks high score support and needs some difficulty options, maybe a better title screen too. bs.a78

And graphics by @TIX

It's not specifically to do with the sound chips. The break functionality works by adding extra code at run time, effectively hacking the games. As a result it works with some games, but not with others.

On the GD menu, move to the game and press the right button which will bring up a sub-menu. On the break option, moving the joystick left/right will toggle between enabled/disabled. Change it to disabled then move down to start game and press the left button to launch it.

I think I know what's going on. Firmware 23.11.2863 added "auto-fix for bad headers for known ROMs": https://forums.atariage.com/topic/353425-news-firmware-update-notifications/?do=findComment&comment=5356799 With the file @Trebor posted, the GD checksums the cart image and identifies it as the Portal demo and assumes it's the original version without the covox or irq bits set in the header (which didn't exist at the time). It decides to correct the header - but has forgotten to set covox! In the file I posted a couple of unused bytes are changed, the checksum no longer matches and the header from the file is used. Regarding the crash, are you running with break disabled? The break functionality inserts extra code which can cause issues. Unless you are looking to cheat a game, I would recommend always running with break disabled.

I only have my NTSC 7800 set up at the moment, which is not ideal for testing the Portal demo (PAL only) but it does run to a certain extent. I get the same (wrong header, no covox). I copied the header bytes to a completely different program and that loaded without issue. I modified a couple of unused bytes in the demo and the wrong header warning went away. I don't know if the GD is doing something specific for this demo? You now get the covox audio although the pokey music is very quiet (compared to what it was before). Looking at the header bytes, it has irqpokey2 set. This should really be irqpokey1 (I use the pokey @ $450 for the IRQ). I set this instead and it didn't make any difference. Portal (Demo) (PAL) (20230813) (9E5AAC54).a78

I did a quick test on the Lynx which is 160x102 using the same graphics. I think you do lose some of the smoothness with the low vertical resolution, although you don't really notice that on a real Lynx since the screen is so small. galt.o galt.lnx

I've not made a single penny from anything I've done, so monetary value has never been an issue. However, when there were unlicensed games in the store it felt like a buffer; if the IP rights holders weren't going after those, they were unlikely to go after me. Galagon looks fantastic but it's not really fair to compare a game which runs on a modern day ARM processor, to one that runs natively on a 40 year old 6502. To get an idea of what would be possible with a similar approach on the 5200, take a look at some of @Wrathchild's A8 Uno cart demos (https://youtu.be/D5BMyeijeUI?feature=shared). While ARM games can make better use of the 2600's graphics, they are still limited by them and I'm not sure that level of flicker would be acceptable on the 5200. Otherwise a sprite multiplexer would be the simplest approach, but I used one in AtariBlast! where I purposely arranged the patterns to avoid flicker and there were still complaints! @TIX already contributed the sprites.

That was a nice surprise, thanks for choosing it as a HSC game. I had not played it for ages, so with some trepidation I loaded it up. I carelessly lost 2 lives early on but in the end managed not to embarrass myself: I played a couple of games of Checkered Flag but that would be too embarrassing to post my times.

Yes, I think if I did return to it I'd take that approach, especially as all the unlicensed games have gone from the store. That was a buffer to me; if publishers weren't going after unlicensed games being sold, they weren't likely to go after a hobbyist posting their homebrews for free. With Atari releasing new hardware capable of playing these old games, I wonder if publishers will be stricter regarding homebrews. Probably it would just be a cease and desist letter, but I don't feel it's worth taking any chances. There's (basic) collision detection in the version above, to make use of @Synthpopalooza's explosion sound effect.

I think it's unlikely I will ever return to it, but I did incorporate some of @Synthpopalooza's sound effects. g5200.bin build.zip