Simultaneous Systems

[KevKelley]

I was wondering if it is possible to write a program on two separate carts and run it on two separate Ataris controlled by a single controller and combining the outputs.

 

 

[CapitanClassic]

Like a PlusCart? Or like this Compumate system.

Or Gameline (really only used to download games)

https://en.m.wikipedia.org/wiki/GameLine

I guess the biggest question is, how are you going to transmit the control signals (joystick/difficulty switches:etc) from one Atari to the other? 

Edited September 4, 2020 by CapitanClassic

[KevKelley]

I was thinking of the limitations of the system so I was thinking more like this:

 

You have 2 Ataris.

 

Both outputs go to the same television.

 

One controller is plugged into both Ataris using a splitter to keep inputs the same. 

 

A program is written on two different cartridges, each containing half of the program. An example would be sprite data for Player 1 containing different information on both carts so that the Sprite would be more complex than what would be possible with one system. Or music data and sound effects on one cart.

 

This may be an extremely simplistic take on what I was thinking and may serve no practical purpose.

 

[CapitanClassic]

3 hours ago, KevKelley said:

I was thinking of the limitations of the system so I was thinking more like this:

 

You have 2 Ataris.

 

Both outputs go to the same television.

 

One controller is plugged into both Ataris using a splitter to keep inputs the same. 

 

A program is written on two different cartridges, each containing half of the program. An example would be sprite data for Player 1 containing different information on both carts so that the Sprite would be more complex than what would be possible with one system. Or music data and sound effects on one cart.

 

This may be an extremely simplistic take on what I was thinking and may serve no practical purpose.

 

I don’t think this is possible, mostly because of this part, “Both outputs go to the same television.” It is quite possible to connect multiple devices to the same coax connection on the TV, in fact people regularly used to daisy multiple RF boxes on the back of their TVs. The issue would be with displaying the signal from two units simultaneously. I think I have actually done something like this, having an Atari on channel 2 and an NES on channel 3. I think all you get in that situation is noise bleeding in from the other channel. If they were both on the same channel, my guess is the interference would just be greater.

 

Both Ataris are trying to output a valid NTSC signal, and neither clock is synced to the other clock. Due to this, my guess is the colorburst would be located twice and at different times, the scanline data  would be different and out of sync.

 

I suppose something like this could be accomplished, since the Sega 32x exists. but it would require additional hardware for the two Atari. In the example of Doom 32x, the Genesis and the 32x are responsible for drawing different parts of the screen. There is a cable that passes video between the 32x and the genesis, if it is removed, you will still see the HUD from Doom and hear all the sounds, but the actual room/FP perspective isn’t drawn. 

[KevKelley]

I figured there would probably be more needed. I remember back in high school I rigged all my systems together using various splitters and devices. There was a lot of noise to deal with.

 

I look at the add-ons for the system, both new (AtariVox) and old (Supercharger,Compumate) and it always makes me wonder. I suppose there could be a Sega-like add-on for the Atari that could accomplish what I am thinking, maybe run the AV to the add-on in the cartridge port. 

 

 

I guess then there is the question of "What's the point?"

 

I love the debates regarding things like legacy games vs things like DPC+. I like the charm of the Atari graphics and limitations, as it forces more of a focus on gameplay, but at the same time, why not?

 

I like trying to find new ways to do things. That usually leads me down many Rabbit Holes...

[Keatah]

SLI style.. Visionary!

Edited September 5, 2020 by Keatah

[KevKelley]

3 hours ago, Keatah said:

SLI style.. Visionary!

What is SLI?

[Mr SQL]

18 hours ago, CapitanClassic said:

Like a PlusCart? Or like this Compumate system.

Or Gameline (really only used to download games)

https://en.m.wikipedia.org/wiki/GameLine

I guess the biggest question is, how are you going to transmit the control signals (joystick/difficulty switches:etc) from one Atari to the other? 

This is very cool! Compumates are very colorful when they talk to one another!  

 

I notice Compumate BASIC uses tokenized BASIC,  but I suspect you could type the whole commands to create a pure ASCII file though it wouldn't work when you typed RUN - but I wonder if you could save the code and RUN it in bB or SuperCharger BASIC.

 

20 hours ago, KevKelley said:

I was wondering if it is possible to write a program on two separate carts and run it on two separate Ataris controlled by a single controller and combining the outputs.

 

The joystick ports are bidirectional so two Atari's could use each others other joystick ports to share controller signals, the same program running on two separate carts like in the Compumate video could also be made using the joystick ports to combine both Atari's joystick controller inputs and outputs.

 

Idea: 

You would be writing your own protocol for this kind of program to init because it would need to do a handshake so that both instances could commence the game at the same time, one Atari could display waiting for Player2 or something and then they would synch and the game would start and it would have the same output on both displays.

 

[Keatah]

6 hours ago, KevKelley said:

What is SLI?

ScanLineInterleve.

 

An old outdated technique where two PC graphics cards are connected together to the same monitor. The workload is divided among each GPU. Each card renders even/odd scanlines for a hard 2x increase in performance.

 

There was a time when "elite" gamers were doing triple and quad SLI. Thankfully the trend today is back toward single GPU configurations.

 

[KevKelley]

Ah. Now I kind of want to try this with a simple little program and 2 Ataris. Just need a second harmony cart.