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Atari 2600 Programming Tutorial
An anonymous reader writes "Anyone want to learn how to program the Atari 2600? 128 bytes of RAM, and you feed the TV each scanline yourself! There's a tutorial running on AtariAge. So far, its being updated every day. Good stuff." Sure, it might not be the most practical of platforms, but what other 20 year old platform is so dear to our hearts?
The '2600 has only one line of video memory (to oversimplify the architecture). This means that you have to count clock cycles exactly and do most of your work between the last pixel of one line and the first pixel of the next, or between one frame and the next.
Bottom line: This machine is harder to program than probably anything else you've ever worked on, and not necessarily in a good way.
Even if you're interested in classic gaming, wouldn't you rather spend your own clock cycles, say, porting some classic games to your favourite current architectures? If you can really use the challenge, maybe you should study the '2600, and reverse engineer them to make sure the conversion is accurate...
t would be nice to find programmable ROM cartriges for the 2600.
Sorry, but the Cuttle Cart has been discontinued. I'm sure there are alternatives, though.
Another interesting idea is for some small company to develop gameboy-size atari 2600 pads with most of the games built in. Could even be incorporated into cell phones, now that I would buy.
Go ahead.
But if we could only combine current media (an 8/16 MB compactflash card could hold every version of every game ever written for this machine) you'd have something. Especially now that Sean Kelly doesn't seem to be able to offer his carts for sale any more. Sorry.
I should really have split this to 3 different posts to max the karma benefits. Oh, well. Maybe I'll get the rest in offline karma.
The thing is that on any given scan line one can draw two independent objects, two players. Either can be doubled or even tripled, but then they need to be identical in color and shape (barring some very clever, very tight programming), which doesn't work for the ghosts. So, they drew two ghosts on one screen, then the remaining ghost and Pacman on the other, alternating this way and hoping that persistance of vision would make it all OK, but they only did this when the various objects fell on the same scan line. As a result, the screen will be just fine until three objects lie in the same row, and then it begins to flicker until they separate.
This next song is very sad. Please clap along. -- Robin Zander
They were willing to sacrifice the appearence of the game in order to make the gameplay more like the original. The could have taken the approach that many other companies did with their 2600 maze games - make sure that there were never more than two objects on the same line at the same time. But then the ghosts wouldn't behave the way you'd expect.
As you mentioned, it might have been possible to use doubling and tripling, but I suspect that there wouldn't be enough time on the scan line to do all the repositioning (Assuming you don't want your ghosts to be limited to a fixed distance apart).
Repositioning on the current scan line for the current scan line is tough to accomplish (I used to think it was impossible until I saw Galaxian).