Would it be possible to have a 5200-to-7800 adapter produced?

[Giles N]

45 minutes ago, Flojomojo said:

I think that low demand for such a device is the main obstacle. 

I think that a built-in eshop with arcade-titles and atari-console-software-download service could do a lot.

 

One could also build in cart-slots for NES and SMS, Genesis and SNES so you would have a box with 8 slots lined up in two rows.

 

And as to eshop-download:

to make available Atari400/800 games (lets say 2-10$ each), which would really expand the catalogue.

Edited September 3, 2019 by Giles N

[Giles N]

I’m not saying anything should be left to chance here.

 

It would have to be a quality-unit with quality-controllers, being able to run old carts and providing availability for the titles for these systems (and possibly more).

 

Which could mean that Atari or whomever would or could do such stuff would have interest in providing professional output, professional availability for the Homebrews made later.

 

 

Edited September 3, 2019 by Giles N

[Giles N]

15 hours ago, gambler172 said:

Works perfect......plays all my 7800 games on a 5200.....

A guy named Mike Mallori made it....but this is another story.

Its cool stuff for sure, but it was more the other way round I meant, since it then could play 2600, 5200 and 7800 games...

 

...but wait; can this converter play 2600 games on the 7800 via the converter?

[Synthpopalooza]

Would a 7800 adaptor be able to use the 5200's POKEY chip for game sounds?

[Lynxpro]

On 9/2/2019 at 8:59 PM, gambler172 said:

Works perfect......plays all my 7800 games on a 5200.....

A guy named Mike Mallori made it....but this is another story.

 

Do tell. It would certainly improve the quality of this thread.

[scotty]

On 9/2/2019 at 9:45 PM, jaybird3rd said:

I know this isn't exactly what you're describing, but there was a 7800-to-5200 adapter produced, though only as a prototype:

 

I actually touched and held that very device at ReplayFX a few years ago.  Steve Golson from GCC was speaking at the show and brought it with him.  I had taken a bunch more pictures, as he had signed 2 of my Ms. Pac-Man marquees as well as both my 7800's, but for some reason there are some photos missing on Google Photos.   

 

EDIT:  Found them (see last 2 pics)

 

 

 

Edited September 12, 2019 by scotty
2 photos added

[SearsRoebuck]

Well, to the OP know that you aren't alone in wanting this exact device. I can't justify the 'floor space' of a 5200 ie my TV stand can only hold so many systems, but do miss a handful of titles. Since I use my 7800 to do everything 2600 as well it would be nice to have the ability to do 5200 games too. 

[PacManPlus]

I would think it would be more like something that would plug into the 'expansion port' (for those consoles that still have them) like the laser disc was supposed to, being that it would just be a video/audio/power pass through like the 2600 adapter for the 5200 was.

[+Ryan Witmer]

I'm not a hardware guy, but I'm a 5200 programmer with an interest in the 7800, and from my understanding a device like this would probably be possible.

 

The 5200 and 7800 use the exact same 6502C CPU, as far as I can tell, so the 7800's processor should be able to natively run 5200 code.  That being said, I'm not sure if differences in the bus configuration would allow the code to work correctly, and any adapter might need to contain its own 6502C.

 

The 5200 has 16KB of RAM, whereas the 7800 only has 4KB, so an adapter would need to include this extra RAM.  I doubt it would be possible to simply extend the 7800's RAM with another 12KB, so it would probably need the full 16KB.

 

The adapter would also need to contain a GTIA, ANTIC, and POKEY chip.  GTIA and ANTIC are the graphics chips in the 5200 and I'm not sure how easy those are to come by these days.  The 7800 only uses POKEY for sound when it's present, from what I understand, but the 5200 uses POKEY for a whole lot more.  In the 5200, POKEY is responsible for scanning everything on the controllers except for the primary trigger, which GTIA handles for historical reasons.  It also does random number generation and few timer related things, so it's an essential component of the system.

 

I doubt that the 7800 controllers could be used at all, even with 5200 games that don't use the keypad.  The digital signals from the controllers would somehow need to be mapped to analog signals that POKEY recognizes, and I doubt the 7800's circuitry could do that in a way that would work.  I state again that I'm not really a hardware guy, so I could be wrong about a lot of this.

[SearsRoebuck]

I think you're probably 100% right about what would be needed, but the sad thing is I don't think there are enough of us interested in such a device to justify one, unless it were made in very limited numbers and priced very high.  Those POKEY clones that have been discussed here I guess have issues with 5200 instructions from the controllers, and personally I don't want to see any more Ballblazer cannibalized (about to buy some just to hoard from people trying to do just that).

 

That doesn't even begin to address how the 7800 would handle the 5200 controllers, unless the 'adaptor' also had controller ports like the Colecovision 2600 adapter did. 

Edited September 16, 2019 by dmaxwell

[Trebor]

I agree with PacManPlus.  It would be very similar to the concept of the Atari CX-55.  Plus it would need the addition of Joystick ports.  It would essentially be a 5200 stacked on top of the 7800, instead of the individual console sitting next to it, minus cables for video/audio and power.