Common Atari 2600 Clone, lots of questions.

[Mef]

Hello everyone!

 

This will be my first post here, so I'd like to throw in a little background first.

 

I was born in 1982 and spent large portion of my childhood playing oldchool 8-bit games (which is propably typical here).

The older I was getting, the stronger I desired to revive my old Commodore 64 and getting some Famiclone like the ones

that were very popular during my adolescence.

 

Now after almost 30 years have passed, I've finally brought these plans to fruition and not only I got 2 working C64's

a NES and a quality Famiclone (Pegasus IQ 502, one of the best available in my homeland back in the old days) but also

a friend of mine, knowing my passion has given me a broken Atari 2600 clone he's found in the attic.

 

At first I was like - I never really played Atari VCS or simillar, but then I realised that I've seen Pitfall and River Raid at my

grandpa's house way before any of us got a "home computer" or any of the afformetioned consoles. Quick call and it

appeared that I have indeed seen an Atari 2600 back then, even tho my memories of it are very foggy (hey, I was propably

below the age of 5)!

 

Invigorated with these news, I decided to finally get myself together and do something with this sad broken clone.

 

 

Its one of those typical "Rambo"/"Rinco"/"Sankyo" xxx-in-one consoles looking exactly like a black four-switcher minus

the Atari logo and with BW/Color switch exchanged by "Game Switch" and Channel 2/3 with 32/128 Games (it claims

to have160 onboard but this ofcourse is bullshit).

 

Here's some more details (I'll post pictures if needed, but its almost identical to this one).:

 

Sticker on the back says:

TV GAME COMPATIBLE

2600B

NO. 900150496

 

Printed on the board itself:

Jone Yuan Telephonic Enterprise Co., Ltd.

CY2600B - 4609

 

Printed on CPU:

6591

9102A

823410

 

Printed on ROM chip:

JY0001P

 

Apart from that, nothing worth noting apart from 2 small DIPs:

- Phillips one:

HEF4011BP

714790T

Hnn9105P4

- Mototolla one:

(M) MC 14024BCP

FFFG9043

 

The cartridge slot appears to by fully wired and functional.

The switch in top-right corner has 2 positions labeled 32 and 128

 

 

 

After this introduction, here's a couple things I'd like to ask you guys.:

 

- Is it possible to reinstitute the BW/Color to the circuitry? In the built-in ROM there are games like Starmaster

which recquire this switch for crucial features (displaying the star-map).

 

- I've found an info that this clone's CPU (or rather VCS-on-a-chip) outputs Luma on pin 27 and Chroma on pin 29,

so if they're separate does it mean one can build an S-Video mod for this console?

 

- Do these consoles play original carts which use bankswitching/extra onboard RAM? (Not sure whether I used the

proper terms, anyway I mean games like Pitfall 2)

 

- Last but no least: This consoled arrived to me after some major mishap with previous power supply. Most propably

someone messed up the polarity. With my poor electronics knowledge I've located an obviously swollen 16V 1000uF

capacitor and replaced it with a new one, the 7805 stabiliser was blown as well and after fitting it with a new one

the "Video Game System" sprung to life and it plays very well, BUT... I'm not sure whether the JY0001P ROM was

really unharmed. See, most of these systems really had 128 games, mine only has 64.

 

When you look at this list in other thread, here's how my console works:

- When the switch is in 32 position, games listed under BANK B are available.

- When the switch is in 128 position, it starts just like BANK C from the list but it lacks the whole part from where it should

skip to BANK A up to the point when it goes back to BANK B again at the very end. In other words thera are only the first

32 games from BANK C and then 32 from BANK B. Oddly enough, when cycling thru these games in 128 mode, after

BANK B ends, it doesn't go back to the beginning of BANK C but will only cycle thru BANK B just like in 32 mode, untill

the console gets hard reset (power off and on again).

 

You guys think I just got a 64 games version or could the ROM be busted?

 

P.S. I really apprecieate it if you had the patience to read this wall of text!

[Ranthulfr]

I don't have the answers you seek but welcome to Atari Age!

[alex_79]

I have a similar clone console, altough mine uses a different atari-on-a-chip package that is 40 pins only. My console can only use joysticks which contains mechanical switches; it doesn't have paddle lines nor bidirectional ports and the joysticks and console switches are wired in a 5x3 matrix scheme which reduced the number of pins on the chip. It lacks the b/w switch too. I've found that it has some problems playing cart with bankswitch and added ram, but the behaviour is not consistent with all carts. For example it plays "Crystal Castle" just fine, while it doesn't like "Super Football", and both carts use the same bankswitch method (Atari 16kb with 128bytes of added ram). I only have very basic electronics knowledge, so I don't know if this a bug in the design of the console or if it's due to some component that it's failing.

 

- Is it possible to reinstitute the BW/Color to the circuitry? In the built-in ROM there are games like Starmaster

which recquire this switch for crucial features (displaying the star-map).

You can try tracing the board and searching for unused pins on the AOAC near those for the other console switches. Unless it uses some weird connection scheme like my console, the switches just ground the corresponding pin when pressed, so you could easily add a b/w switch once you find the correct pin.

 

 

- Do these consoles play original carts which use bankswitching/extra onboard RAM? (Not sure whether I used the

proper terms, anyway I mean games like Pitfall 2)

I think that the best way to know is to test the console with different carts. One source for incompatibility is the fact that those consoles detect the presence of a cart in the slot by checking if a pin is grounded or not. Most carts connect pin 24 to ground internally but there are a few exceptions: some Activision games leave that pin unconneced and the Melody board (used for homebrews and Harmony cart) uses the pin to put the cart in programming mode. When using those carts the console won't deselect the internal games causing a bus contention with the cart rom and the game will crash. A simple workaround for this is to wire a switch to manually ground the pin in the cart port of the console to force the use of the external cart when the autodetection doesn't work.

Edited May 20, 2012 by alex_79

[Mef]

Thanks for all the anwsers, Alex!

 

I'll try with b/w switch tommorow and let you know of results.

[Syntaxerror999]

FYI starmaster also uses either dificulty switch as a toggle for the star map.

[Mef]

I wouldn't have ever thought of that.

 

Thanks!

[vgeorgiev]

Hi guys,

 

I am new here.

I found this Atari clone in my parents house.

I am not sure this is mine or a friend of mine gave me....

 

Anyway I tried to run it.

The 7805 was missing. I put a new one.

Connected it to a LCD TV.

The TV found 3 channels, but no picture at all. Only stange grayscale patterns.

Picture changes when I press start or change game buttons....

 

That makes me thining that the CPU is working.

 

Here are some pictures.

It seems this PCB is almost the same as Mef's one.

 

I couldn't find any info for any chip on this PCB.

How can I connect this PCB to AV input of my TV.

I checked some pages where 6592 CPU can provide chroma and luma on 27 and 29th pin.

Same for 6591 ?

 

CPU is 6591. Joysticks are directly connected to the CPU.

 

 

Another chip. I guess this is the ROM. It is parallely conneted to the cardridge slot.

[vgeorgiev]

Hi all,

 

I think that the crystal resonator value is not the propper one. It is 17.734475

I guess it should be something like 3.5MHz for PAL.

[vgeorgiev]

OK, I got the schematics from here: http://atariage.com/forums/topic/199397-2600-clone-capable-of-av-mod/

I put a LED to pin 12 of the counter 4022.

When I press button S1 then LED toggles.

So I concluded U1 (4011), U2 (4022) and Q1 working OK.

However I have 0 channels found on the TV.

Still no image on TV.

 

On Tuesday I will replacve the XTAL with 1MHz one. I do not know why current one is 17MHz...

 

Edited January 4, 2014 by vgeorgiev

[Bladiclab]

Hi, vgeorgiev, i have atari clone based on the same controller 6591, i got it two months ago in condition "dead".

I tried as you connect it via coaxial to my tv and didn't find anything, so i just took mixed chroma and luma signals after the transistor, that's worked perfectly, i connected it to my oldschool tv, also i took sound from the coupling capacitor connected to pin 20, that's all worked, but after some time of use it is instantly died and i didn't find out how it happened for now, maybe it is my fault.

 

For you i can say, that 17.734475 MHz crystal resonator is OK, i have the same, as you can see, 17.734475 divided by four is 4.433618, same value as PAL's carrier frequency, you can check it by Google.

 

Sorry, if my English is very poor, i'm from matryoshka mother Russia. :3 My advice is to first: check you chroma-luma signal and sound, second: if OK, then you can wire some stuff and f*ck that coaxial, else try to fix it (but this may be a little more tough way).

 

P.S. i think that my atari might have died by overheating input linear regulator LM7805, because power supply was not original (didn't mesuared real output voltage ), maybe that has created killing power surge.

Edited February 3, 2014 by Bladiclab

[RupanIII]

How did this turn out?
I'm all for mods but, how does all of this compare to just adjusting the TV Color down to Zero while you play?

[alex_79]

If you're referring to adding a Color/Bw switch, keep in mind that, despite how they're labeled, the 5 switches on the console (tv type, left and right difficulty, select and reset) are just inputs in the same way as the joysticks and each game might use them for different things than the originally indended purpose. Some games require the Color/Bw switch for gameplay ("Secret Quest", for example) and aren't playable without it.
Some of the early games used it to select a different palette optimized for BW tvs. If you turn down the color on the TV while playing "Basketball", for example, the two players are almost indistinguishable if the switch on the console is in the "Color" position.