7 replies to this topic

[johnki]

Alright, I was recently looking into how receptive different systems have been to homebrew, and had seen on the Wikipedia article that the Magnavox Odyssey's homebrew community is almost non-existent.

To be honest, the Odyssey predates me by a bit, so I'm mainly looking for clarification, since information on the web seems incredibly scarce...the Odyssey isn't traditionally programmed is it? Rather, it runs on one of a set of eleven supplied game logic cartridges and the game creators create an overlay and set of rules for the system, right?

If I'm understanding that correctly, is there a way to create more cartridges? Maybe even just program the logic for a cartridge for use with an emulator? Furthermore, ARE there any emulators?

Thanks in advance.

[atari2600land]

From what I understand, and correct me if I'm wrong, technically you could make a cartridge that made the ball and players do different things, but it would be next to impossible because you'd have to have the correct machinery to manufacture a cart, so basically what it all boils down to is how to make the 12 carts in existence do different things and play by different rules. There is an Odyssey emulator, but it's not a very good one. You can download it here: http://www.pong-story.com/odyemu.htm

[johnki]

So the "programming" was entirely based on how the cart was manufactured, as opposed to what was written to it? If so, I think I understand how it works now.

And heh, I can see how it'd be a bit difficult to emulate every game.

Most of the games only had gameplay inside the system though, didn't they? Most of the, I'll say, "management" aspects (score keeping, time keeping, etc) were done by the player on paper, with a timer, etc, right?

[atari2600land]

johnki, on Sat Dec 3, 2011 8:34 PM, said:

So the "programming" was entirely based on how the cart was manufactured, as opposed to what was written to it? If so, I think I understand how it works now.

And heh, I can see how it'd be a bit difficult to emulate every game.

Most of the games only had gameplay inside the system though, didn't they? Most of the, I'll say, "management" aspects (score keeping, time keeping, etc) were done by the player on paper, with a timer, etc, right?

I don't know very much about the technical aspects of the Odyssey. But I can tell you that score keeping and all that stuff was indeed done by the player(s).

[atari2600land]

Re: Wikipedia:
"The Odyssey uses a type of removable printed circuit board card that inserts into a slot similar to a cartridge slot; these do not contain any components but have a series of jumpers between pins of the card connector. These jumpers interconnect different logic and signal generators to produce the desired game logic and screen output components respectively."

[johnki]

atari2600land, on Sat Dec 3, 2011 8:42 PM, said:

Re: Wikipedia:
"The Odyssey uses a type of removable printed circuit board card that inserts into a slot similar to a cartridge slot; these do not contain any components but have a series of jumpers between pins of the card connector. These jumpers interconnect different logic and signal generators to produce the desired game logic and screen output components respectively."

Gotcha. Wonder if there's any documentation on how they worked. Doesn't sound impossible to make new ones, but possibly pricey (well, relatively). I'd have to do a bit more research, and, of course, have a reliable source of information on how they worked.

But yeah, thanks for what info you have passed on. I'm definitely curious as to how development of a homebrew Odyssey game would go.

Edited by johnki, Sat Dec 3, 2011 8:54 PM.

[theloon]

I'm pretty sure someone did make a homebrew for the original Odyssey here. I'd check the homebrew section. I'd assume it's less about "programming" and more about manufacturing the "cart" and screen overlay.

[Retro Rogue]

You can't emulate the Odyssey, there's no CPU or code to run. Best you can do is simulate the logic blocks and circuitry, which is what the only current simulator does. The Odyssey is a discrete logic state machine, just as all pre-CPU arcade games were as well. The "game" itself is done directly through circuitry that represents different aspects of the game. (I.E. in PONG you have a circuit that generates a paddle, another for the ball, another to change the direction of the ball, etc.) The current state of any input device (such as the paddles) changes settings which effects the overall "state" of the entire circuit and how all the parts interact as a whole. In the case of PONG again, it effects the motion circuitry of the paddle.

With the Odyssey you have the need to play multiple games in this format, rather than just a single game as in the arcade. So the multiple games were each designed separately (see Ralph's site or book for more info) and then eventually put together with common logic circuitry "blocks". Each of these blocks reside on a circuit card inside the Odssey, and interact with each other via the circuit set up with the jumper cards.

As for new games, you have to use the logic that's already built in to the console. That's what was done for the previous homebrew Oddball. Most of the game play for Odyssey games were based on the overlays and imaginary "rules" anyways, sort of like a board game. The logic inside just throws up different objects on the screen and changes their behavior and control.