Can 2600 be built from scratch?

[RCmodeler]

Is it possible? Are all the parts that were available in 1977 still available now?

[Ian Primus]

Well, yes, and no. The Atari 2600 used mostly off the shelf parts, but the main chips (TIA, CPU and RIOT) are not quite as easy to find. There are still places that have new, old stock 2600 chips, like Best Electronics, as well as some of the people here on AA. That 2600 could be built from scratch relatively easily, provided you have those three chips. The rest of the parts are common resistors, diodes, capacitors, etc... and can be obtained at any good electronics store.

 

I would imagine that with modern FPGA technology, it would be possible to recreate the three main chips, possibly even on a single FPGA. It is also no doubt possible to create an "Atari on a chip" with modern technology, that would require very little additional hardware to work. I think those little joysticks with 20 Atari games in them that they sell these days have something like that, but I don't think that it is a true "Atari on a chip", I think therre is some sort of microprocessor based emulation, or at least a different implementation of the system, since I heard that one person that has one noticed that Asteroids doesn't flicker. I have never taken one of those joystick consoles apart, however, so I'm not sure how they work.

 

I know that the Atari could be created with off the shelf parts back in the 80's, since Coleco made clones, as well as their Atari 2600 adapter for the Colecovision, and IIRC, didn't Atari lose some lawsuit over those things? I've never taken a Coleco 2600 cart adapter apart, so I don't know how they did it, but I do know that it's basically a complete Atari 2600 that just pipes the video through to the Colecovision. Same thing with the adapter for the 5200. Anyone know if the Coleco adapter used the same main chips as the real 2600, or did they use something different?

 

Ian Primus

ian_primus@yahoo.com

[DanBoris]

The 6507 CPU and 6532 RIOT chips where off the shelf components, but the TIA was a custom Atari part. Coleco reverse engineering this chip and made thier own clone of it which is used in the Colecovision 2600 adaptor as well as Coleco's Gemini 2600 clone. Atari did sue Coleco over this but according to what I have read it was settled out of court and Coleco was allowed to continue the sale of these items.

 

Dan

[Video]

If I remember right, there was a lawsuit in the early eighties that Atari lost. It was either with Activision, over licensing rights, or with Coleco/Intelivision over the 2600 plug in. I don't remember wich, but Atari wanted money for it, and basically lost on account of the system being made from off the shelf parts.

 

Weather those parts are still available, just depends on their usefull ness in other things, like little kids toys, maybe that talking GI Joe has a 6502 in it?

[sebastius]

http://www.mindspring.com/~2600onachip/ < this guy is designing a atari 2600 on a chip. He is slow with updates (6 months between updates is no exception), but he has come to this point:

Current results:  

 

So far, the TIA and PIA synthesizable cores have been completed and are 100% functional. The TIA design took me approximately 150 hours and the PIA about 10.  

 

As for the 6502 core, I have completed the architecture (ALU, registers, datapath) and I'm working on the microcode, the most time consuming part of the design.

[AtariDude]

I would think that anything is possible given enough money thrown at it. Building a 2600 from scratch should be possible but it would probably be easier to just get parts out of non-working 2600 systems and then taking the parts that still work from them and putting it all together.

[mos6507]

I think it's quite remarkable that Coleco made a TIA clone if they didn't have any schematics (unlike the guy who's doing the 2600-on-a-chip).

 

Most games that use TIA tricks work on the Gemini and the adapter, don't they?

 

What about the Intellivision System Changer?

[DanBoris]

I think it's quite remarkable that Coleco made a TIA clone if they didn't have any schematics (unlike the guy who's doing the 2600-on-a-chip).

 

Remeber that this was at the height of the video game industry so Coleco probably had the money to throw a couple of engineers at the job full time.

 

Dan

[Susuwatari]

If you have those 3 main chips, you could build a working 2600 from ground up. But I'd get those one chip design and tuck it inside a pocket TV, add a cart port and control pads and not worry about wasting too much space.

[jsoper]

If you have those 3 main chips, you could build a working 2600 from ground up.  But I'd get those one chip design and tuck it inside a pocket TV, add a cart port and control pads and not worry about wasting too much space.

Yeah, I'd like to do that also. There's even some 2600jrs built with just one chip,

but they're very rare. I haven't found one yet. One RCA lcd tv even has an internal ribbon cable

and one of the signals is composite video. It might just be possible to build a portable into a GBA case.

[JB]

I doubt it'd be feasable to create a TIA clone out of standard off-the-shelf transistors. But that'd be cool if you could.

...

*remembers the DeLorean in Bck to the Future 3, with the computer strapped to the hood*

Errr... maybe not.

[phoboz]

On 11/12/2003 at 5:05 AM, JB said:

I doubt it'd be feasable to create a TIA clone out of standard off-the-shelf transistors

Wouldn't be just a little bit easier to create a curciut with the same function as the TIA using 74-series logic ICs?

Or even programmable array logic ICs from the PAL series?

 

PS. I belive that the first protoype of the Amiga custom chipset was made using discrete logic ICs.

Edited June 30, 2021 by phoboz

[+DrVenkman]

25 minutes ago, phoboz said:

Wouldn't be just a little bit easier to create a curciut with the same function as the TIA using 74-series logic ICs?

Or even programmable array logic ICs from the PAL series?

 

PS. I belive that the first protoype of the Amiga custom chipset was made using discrete logic ICs.

Nearly 18 year necrobump? Damn … good job.

 

[+SvOlli]

20 hours ago, phoboz said:

Wouldn't be just a little bit easier to create a curciut with the same function as the TIA using 74-series logic ICs?

You know about MOnSter 6502?
Now take the following into account:

• the TIA uses more transistors than the 6502
• the MOnSter 6502 has (or at least had) problems to run at 1 MHz, the TIA requires 3.57MHz

So the answer to your question is theoretically: yes, but you'll can't call it "easy" or "easier" in any way.

 

20 hours ago, phoboz said:

Or even programmable array logic ICs from the PAL series?

A well meant tip: it you really want to recreate the TIA, use a programmable logic IC suitable for this: an FPGA. You wouldn't want to go to the tour de France in a clown cycle, or do you?

 

20 hours ago, phoboz said:

PS. I belive that the first protoype of the Amiga custom chipset was made using discrete logic ICs.

They used stacks of wirewrap boards for this. Did you know that they only ran at full speed, once the design was transferred to a chip?

And did you know, that the TIA was also designed the same way and even by the same person was involved (Jay Miner)?

 

And back then at the same time, CPUs were designed by drawing on paper and shrinking these images down and projecting them onto the wavers. Nobody does that any more, because development has advanced.

 

So what's your point?

 

If you want to recreate the 2600, and you focus on the three chips, where are your options:

• CPU
  • new CMOS 65c02 (not all software will work)
  • old new stock 6507, but those are not easy to get
  • old new stock NMOS 6502 with an adapter
  • FPGA replacement
• RIOT
  • old new stock 6532, i found some rather easy on ebay
  • FPGA replacement
• TIA
  • old new stock TIAs, those are hard to find
  • FPGA replacement

And if you've got FPGA replacements for all three chips, you could think about joining them in one, recreating the legendary Janus chip. This was the approach of the Flashback II, but it was only half-baked, though. Development stopped, when all games included with the console worked. A lot of corner cases of other software were not covered.

[Obadiah64]

I remember these from YouTube.

 

 

 

[Video]

Nothing wrong with necrobumping lol. I always wondered what "off the shelf" equivalent coleco used for their 2600 adapter? ( unless they bought tia and others off ataris shelves lol ) As I said (nearly 18 years ago) Atari lost a suit over that because it used off the shelf components.

 

With the number of aoac systems out there (both modern flashback types, and old stuff like 7800, certain jrs, and odd things like tv boy, I find it strange nobody makes a modern 2600. Don't get me wrong, the dies, or masks (however they were made) are long gone, but there are real physical examples that could be reverse engineered, combine with someone like retron (who either sources or makes their on cart connector) there's no reason there shouldn't be a good modern clone system.

[Capt Moore]

1 hour ago, Video said:

Nothing wrong with necrobumping lol. I always wondered what "off the shelf" equivalent coleco used for their 2600 adapter? ( unless they bought tia and others off ataris shelves lol ) As I said (nearly 18 years ago) Atari lost a suit over that because it used off the shelf components.

 

According to the video below, Coleco used a copy of the tia chip, not a generic one. Atari losing the lawsuit was a myth, Coleco settled the lawsuit by paying Atari a royalty for every 2600 adapter sold. 
 

 

[Keatah]

I'm fairly certain that Intel hides Atari 2600s in all their CPUs.

[Keatah]

You just use Stella to reveal it.

[+SvOlli]

On 7/2/2021 at 7:19 PM, Obadiah64 said:

I remember these from YouTube.

Here Ben sacrifices a 2600 to get the chips. The question was to build a new one, not convert one to another form.

[Jacobturner2502081@gmail.com]

Wait...so using ttl might take a very very long time to substitute a TIA and might be quite challenging, however what if you implemented don lancasters cheap video solution to the machine by adding a EEPROM programmed with a subroutine just as it describes in his book to be able to meet the timing and refreshrate needed to produce video output? Plus it could cut down on costs as well as IC's needed plus you could use your own design implementing this method along with a 4k DRAM to substitute the 128 bytes of the RIOT as well as a 6521 pia for the controllers and maaaaybe a hex decoder for decoding for the 9 pin ports? Not sure idk but it seems possible to me however I may be wrong. Thanks for reading!

 

- jake

[rlindsley]

Does anybody have the source code for the FPGA chip for the Flashback 2?  It seems like it we had access to that somebody could complete the work to make it compatible with every title. From there we could build an Atari 2600 with a single chip.

Edited January 29, 2022 by rlindsley

[Keatah]

On 11/10/2003 at 6:51 PM, Ian Primus said:

I would imagine that with modern FPGA technology, it would be possible to recreate the three main chips, possibly even on a single FPGA.

Would even that be enough?

 

It wouldn't be instant-on since FPGA needs to load a bit-stream at startup. And for the same reason it wouldn't do the double-shot SpaceInvaders trick or any type of "frying". Some sort of one time programmable fabric needs to be used. And it must have the exact timing internally and externally. And it can't dwaddle around configuring itself either. So far I've not seen any remake behave that way.

 

And what about voltage translation for exact accurate controller and accessory operation. 3.3v - 5.0v translation parts are getting harder to find and not cheap compared to the other discrete parts. No one seems to think it important.

 

Real slide switches are important. Seems most recreations I've seen like to do funky push-buttons and not slide switches. For whatever reason..

 

 

Edited January 29, 2022 by Keatah