Ben_Larson

The wording is very confusing. My interpretation would be: even though it says 'same color' in the diagram, it could still mean that they are supposed to be slightly different. Maybe it means 'same color' in the sense that they are both orange (for example), but each one is a slightly different shade of orange.

Keep in mind that the elements in the display list don't really have to be in the order that they appear on the screen as long as they aren't overlapping. They can be in whatever order, really. The way I do it in my Super Pro Racers game (I am using direct mode by the way) is that I just keep track of the DL tile elements that have scrolled off-screen and reuse those entries when new tile elements get scrolled onto to the screen. In that way, the list of tiles pretty much stays the same length, and the elements are just recycled. But then you also have to support sprites, so you have to have some additional display list entries for the sprites that you keep track of separately. Indirect mode horizontal scrolling with sprites on top is probably easier to do, but it generally requires more DMA time I think.

No real updates except to speak of except to say that since the game is feature complete and I haven't found any more bugs, I'm retroactively calling this last release v1.0 (non beta now!). If I find any bugs moving forward I will of course fix them...

Hey sorry, haven't logged in in a while so I just saw this. The piggyback resistor mod was just to increase the sharpness of the image. My 2600jr that I was comparing against not only had better color saturation, but the picture also seemed sharper. The piggyback resistor mod seemed to bring the 7800's video output sharpness in 2600 mode closer to that.

hizzy, you can dramatically increase the color saturation on 2600 games by adding one resistor to the TIA. Here's a post I made about it last year. This was a mod that Atari themselves was apparently doing on the 2600 at one point, but for some reason it wasn't stock on the 7800.

14v is pretty typical for an old school 'wall wart' (aka linear) 9V adapter with no load because they're unregulated. Under load they will be closer to 9V but typically still higher than 9V. If you want one that's actually 9V all the time you would need to get a switched mode adapter. Typically you can tell these from the linear adapters because they're much lighter since they don't have the big transformers in them that older linear power supplies have.

...and here is the version with driving controller support. Thanks to @PacManPlus for encouraging me to do this and providing me with some info on how the driving controller works. Note that the title screen works a bit differently when the driving controller is plugged in: Rotating: Switches selection between # of players, difficulty, and # of laps. Rotating + holding button: Changes the value of the current selection I am gonna call this release v1.0 beta because I think it's feature complete now. racers.a78

Could you use regular DMA for the interior parts of the 48px high sprite, and holey DMA for just the top and bottom? The 'holeyness' would of course affect everything else in the same display list zone, so it wouldn't work if you have multiple 48px high sprites with overlapping and different Y positions...

New version. Changes since last one: * Added support for 2-way and 3-way ties in grand prix mode (previously one of the players would get one point less even if the finishing time was exactly the same) * More optimizations to reduce slowdown * Fixes for glitchy flashing track tiles on certain long horizontal stretches of track due to running out of DMA time * Tweaks to track #3 in the track selection screen so that it's more accurately represented * Fixes so that the number of scanlines is consistent @PacManPlus convinced me to add driving controller support, so that's the next item up on my to-do list... racers.a78

Are you sure the MJE210 is dead? I only ask because I know from my experience working on amps that power transistors can get hot even under normal operation. Did you check it with a multimeter?

Okay, another new version. Here's the changes since the last version: * Fixes for 2P split screen mode to address the slowdown issues (as demonstrated in the ZPH playthrough). The main fix here was to switch to 30Hz screen updates in 2P mode vs 60Hz in 1P mode. The other alternative would have been to omit the CPU car entirely in split-screen mode, which I didn't really want to do. * Tweaks to the starting track positions to ensure the cars are always centered in the middle of the track vertically * Fix for bug that was causing the top row of track 2 to disappear when going backwards on the track * Fix for flickering glitches when cars were at the top of the screen * Time trial timer color changed from gray back to red James also found a very strange bug during the ZPH playthrough where one specific block did not load on track 6. I wasn't able to reproduce this bug during testing but I think I have an idea what was causing it and I think I have fixed it? (fingers crossed ). racers.a78

Okay it's been a little while, but I got a new version. Changes since the last version: * Increased ROM to 48K and added 2 more tracks * Added track selection screen (see image below) * Fixed bug where P2 car couldn't steer when P1 car wasn't moving * Fix bug where the palette switch at the bottom of the screen on time trial mode was occurring 1-2 scanlines too early racers.a78

Just seeing this thread now. I was there today at the show and I saw the Intellivision booth with Food Fight running. I didn't know you guys were atariagers or else I would have stopped to talk! Next time I guess...

Another new version. Changes since 2024-05-17: * Fixed bug that would cause the CPU cars to steer into the wall if you hit reset on track 3 when they were on the center straightaway and then selected that same track again * Fixed issue so that cars appear partially off the left side of the screen (instead of disappearing the minute they hit the left edge) * Fixed it so that car won't steer if not moving and no acceleration (thank you Philsan for pointing that out) * Tweaked CPU steering on track 3 to avoid hitting the wall on one turn My plan is to add 2+ more tracks, as well as a track selection screen that actually shows you what each track looks like. That will mean going to 48K, which means I will have an excuse to build another dev board. Speaking of which, here's some photos of my current ramshackle dev board for your entertainment. 😁 racers-2024-05-22.zip

Alright, new version... Changes since last version: * Tweaked difficulty. 'Easy' is easier, 'medium' is slightly easier, 'impossible' is slightly harder. 'Hard' is unchanged. * Tweaked some colors. The red lines in the title screen header were very hard to see on real hardware over RF so I changed them to blue. I also changed the time trial and results screens to use gray instead of red for the text backgrounds. * Added a little bit of whitespace above the timer in 'time trial' mode. racers-2024-05-17.zip