why will my 7800 not play 2600 games?

[Professor Gull]

So I dug out my 7800 from 30 years back and this was one we got from Sears back in the day. I noticed my library of games was all 7800 and then reflected back to thinking it did not do 2600 games. Anyone know if they made some models of 7800 without the ability to go back and if not any help in trouble shooting why it does not play them? I can get the model number later if need be.

[+GoldenWheels]

I think it is just a small selection of games that shouldn't run on a 7800, and even then, only certain models:

 

What 2600 carts do not work on the 7800?
There are known incompatibilities with some NTSC versions of the 7800. Games that may not work include Robot Tank, Decathlon, Space Shuttle, Time Pilot, Kool-Aid Man and the Supercharger. In short, 7800s manufactured in 1984 seem to be fully compatible, whereas those manufactured later have inconsistent incompatibilities.

 

http://www.atariage.com/7800/faq/?SystemID=7800#cat3_3

 

There's a lot pf people here with way more technical knowledge than I, I'm sure they'll have some ideas why 2600 games might not work on the whole.

[Professor Gull]

I will check the model later but I tried the following 2600 games and none worked.

 

Kaboom

Casino

Atari Circus

Berzerk

Superman

Asteroids

Space Invaders

Enduro

Night Driver

and Jungle Hunt.

 

It plays all 7800 ones just fine. I will probably end up taking it apart at some point to see what chips are in on the board and their condition. All 7800 games work just fine including Food Fight.

[BassGuitari]

I think my 7800 may not like 2600 homebrews. There's a part in Princess Rescue that's impossible to pass because you get stuck if you jump at the top of the screen instead of gliding forward. I suspect Zippy The Porcupine might have control-related issues with it, as well, because it feels harder to play than one would think (I haven't actually tried it in a 2600 yet), especially compared to Princess Rescue.

Then again, my 7800 also occasionally wigs out with certain 7800 games; in Xenophobe, after a while it will randomly start acting like the fire button on joystick #2 is being held down...even when no joystick is connected to that port. So Player 2 will jump in, stand there, get killed, and jump back in again, rinse and repeat. I think I just have a weird 7800.

[+GoldenWheels]

I will check the model later but I tried the following 2600 games and none worked.

 

Kaboom

Casino

Atari Circus

Berzerk

Superman

Asteroids

Space Invaders

Enduro

Night Driver

and Jungle Hunt.

 

It plays all 7800 ones just fine. I will probably end up taking it apart at some point to see what chips are in on the board and their condition. All 7800 games work just fine including Food Fight.

 

Hmm yeah weird....my 7800 (with an expansion port, I have no idea of the model number/series other than that), plays many of those just fine.

[7800fan]

That's unusual, maybe you have a dodgy 2600-specific chip like TIA?

[Professor Gull]

I think i will just go ahead and take it apart. Maybe the TIA chip is loose or something although I don't hear any rattling. It eh TIA chip well labeled anyone know?

[Jinks]

I think i will just go ahead and take it apart. Maybe the TIA chip is loose or something although I don't hear any rattling. It eh TIA chip well labeled anyone know?

If you can shake your 7800 and hear chips rattling no games would work. I have never heard of any chip falling out completely from any system. In a 7800 the chips are soldered to the board.

[+DrVenkman]

If you can shake your 7800 and hear chips rattling no games would work. I have never heard of any chip falling out completely from any system. In a 7800 the chips are soldered to the board.

Not mine. It's fully socketed. I think all EP and AT-84 systems are. Can't say for later runs of the console.

 

 

Sent from my iPhone using Tapatalk

[SoundGammon]

Hard to say why. If 7800 games work, that means the TIA being accessed for sound and the RIOT is being used for joystick input.

 

My guess is a faulty OS chip!

[FireTiger]

I think my 7800 may not like 2600 homebrews. There's a part in Princess Rescue that's impossible to pass because you get stuck if you jump at the top of the screen instead of gliding forward. I suspect Zippy The Porcupine might have control-related issues with it, as well, because it feels harder to play than one would think (I haven't actually tried it in a 2600 yet), especially compared to Princess Rescue.

 

Then again, my 7800 also occasionally wigs out with certain 7800 games; in Xenophobe, after a while it will randomly start acting like the fire button on joystick #2 is being held down...even when no joystick is connected to that port. So Player 2 will jump in, stand there, get killed, and jump back in again, rinse and repeat. I think I just have a weird 7800.

Check heat issues- either something is heating up and shorting closed or ???

 

I have a 7800 that cannot play Choplifter... the 'warmer' the console the quicker it would fail to play...

 

I have one that only plays 2600 games ... I guess Maria died... and I have one that plays perfectly even the 'sometimes non-compatible' ones

[Jinks]

Not mine. It's fully socketed. I think all EP and AT-84 systems are. Can't say for later runs of the console.

 

 

Sent from my iPhone using Tapatalk

Garsh I leanrt sumthing today.

 

Still if your chips were all shaking out yer 7800 wouldnt play any games.

[Professor Gull]

Well hopefully this weekend I can take mine apart and just see if something is maybe off on a solder point or something. I hope its not something more serious else I will have to go back on the market for another one. But this one is from my childhood so I will have to keep it anyhow.

 

Thanks for the help and suggestions fellas and ladies I will let you know what ends up out of the surgery with some pics as well. Pray for the patient.

Edited February 5, 2016 by Professor Gull

[7800fan]

If you're not handy with repair and can't find obvious issues, you could ask if someone can take a look at your system.

[Professor Gull]

So I opened up my 7800 and all the solder points looked clean and nothing was cross touching anywhere on it. the TIA chip ( which is the chip thats upside down on the board looks fine)

 

AMI 8812TAL

C010444-002

Copywright Atari 1979

-01

C04075

Taiwan

 

Oh well I like soldering but this would be a lengthy process to remove it and then find a replacement. Cost factor does not seem comparable at this point.

[R.Cade]

What does the console do when you put in a 2600 game and turn it on? I don't think it was mentioned...

[Shawn]

So I opened up my 7800 and all the solder points looked clean and nothing was cross touching anywhere on it. the TIA chip ( which is the chip thats upside down on the board looks fine)

 

AMI 8812TAL

C010444-002

Copywright Atari 1979

-01

C04075

Taiwan

 

Oh well I like soldering but this would be a lengthy process to remove it and then find a replacement. Cost factor does not seem comparable at this point.

 

 

Check the edge connector on the machine. I'm betting there is contact being made with the last few pins when you don't have a cart inserted. The reason it would still play 7800 games fine is because it's opening up those contacts when the cart is inserted but the 2600 games don't have those extra contacts on the edges of the cart pcbs and the contacts are staying closed preventing you from playing 2600 games. You will need to push them back a little so they are not making constant contact with eachother. on the left and right sides of the cart port.

 

[Professor Gull]

I will check those pins tonight. When you put in a 2600 The screen flashes black and that is it nothing else. Thanks again folks lets hope the pins does the trick.

[Professor Gull]

Not sure on the pins I get a red screen though now pushing those side pins back though. I wonder how far apart do they need to be. Right now it's a toothpick spread.

[+DrVenkman]

Not sure on the pins I get a red screen though now pushing those side pins back though. I wonder how far apart do they need to be. Right now it's a toothpick spread.

 

 

I don't think that's the problem, honestly. Even without a cartridge in that connector, the pins aren't "closed" they're just a bit closer together. If anything, the spring tension in the metal contacts WEAKENS over time, making the contacts less likely to make good contact on a cartridge PCB edge connector. I've actually had to tighten the pins on 7800 with a toothpick to make better, more reliable contact.

[Jinks]

Try another channel on your rf switch and see if that works.

Check voltages and grounds.

Insert 2600 cart and leave on for 30 seconds and feel for hot chips.

Take a envelop and fold over and spray contact cleaner on it then insert and remove from cart slot till clean.

[Professor Gull]

Try another channel on your rf switch and see if that works.

Check voltages and grounds.

Insert 2600 cart and leave on for 30 seconds and feel for hot chips.

Take a envelop and fold over and spray contact cleaner on it then insert and remove from cart slot till clean.

 

I tried the cleaning and I took it apart and checked the chips they all get warm from what I can tell. I cleaned the slot for the carts as well and checked the center pins to see if maybe they might be looser then the outers but nothing. I am using a direct connect without RF box but could that be the culprit?

[Jinks]

 

I tried the cleaning and I took it apart and checked the chips they all get warm from what I can tell. I cleaned the slot for the carts as well and checked the center pins to see if maybe they might be looser then the outers but nothing. I am using a direct connect without RF box but could that be the culprit?

That all sounds good then..26's are cheap...

[Professor Gull]

I manged to snag a Sears Telegames in the box a couple weeks back so yeah I will let the 7800 do what 7800 it can.