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Unreal History of the Atari 2600
Such_a_geek writes "Atari fans, do you remember playing Gunther Gebel Williams' Cage Cleaner, Typing Tutor, and Peabo Bryson's Cow Tipper on your 2600? How about playing the interactive Foghat 8-track while playing with your Pong action figures? Yeah, me neither. But thanks to this totally fake but quite convincing screenshots in this alternate history of 2600 games, I almost find myself remembering these things."
for what it is worth.. here ;)
check your flash
The war with islam is a war on the beast
The war on terror is a war for peace
I have one of these.
Target, 15 bucks or so. Money WELL spent. How long has it been since YOU held a joystick like that?
perv.
best web host ever
The 1802 was, in fact, used in quite a few space probes, including the Pioneer series, because of its reliability (it was miserably slow by contrast to the 6502 but also much simpler).
Brackets contain world's first nanosig, highly magnified:[.]
i was able to get just a few...site seems to have completely died now. i have typing tutor, hands across america, ms. paul's fish stock hunter, and part of emett-otter's jug-band motorcross.
here's my partial mirror
There isnt much source code per say. Most games were 4 KByte, the biggest were 32 or maybe 64. They were done completely in 6507 assembly, and can be disassembled into essentially what the programmers wrote. The hard part is making sense of it. With effort, and some experience, one can label the disassembly enough to understand whats going on. There are several games where this has been done, and are publicly available. Remember that the atari was very simple, it barely had enough power to draw the screen line by line. Their was a CPU (6507 which was a 6502 with only 13 address lines) and the TIA chip, which was what generated the scan lines for television. Their was iirc 128 bytes of memory, and if one was really sneaky, some ram could be put on the cartridge. The most complex part of atari code is bank switching, where differant segments of a rom are mapped onto the same set of addresses. Having the source would not give any benefit, as it is one step above machine code. The best way to preserve atari title is to have emulators that are as close to a 2600 as possible, thus allowing the titles to still be played.
-- the computer doesn't want any beer, no matter how much you think it does. NEVER, EVER feed your computer beer.
The 2600 reset did not actually reset the CPU, it was just an input that the cart could read and act upon. I know this well since I've written a couple of 2600 demos, and I've used it.
Brackets contain world's first nanosig, highly magnified:[.]
That "MOD PARENT UP" trick is stupid and it's nice to see it fail miserably.
What might have not been clear from your post was that bank switching was game vendor specific and not part of the 2600 itself.
As you said, some cartridges had RAM but accessing it was strictly based on addresssing since the R/W line from the processor was not brought out to the cartridge interface. So you'd have an address space for reading from RAM and a different address space for writing to it.
I recall I once had a bug on an indexed read (the index was incorrect) that ended up reading from the wrong location. It turned out the location it read from was in the RAM write address space. So I read an incorrect value and at the same time wrote an incorrect value all in one instruction.