14 replies to this topic

[atari8warez]

Guys, is there a way to take an OSS cartridge apart without breaking it?. More specifically a MAC/65 cartridge. I recently dusted it off and inserted it into my 130XE but no go (cleaned the contacts too), the computer simply boots into the self-test mode. Tried the cart on a 65XE, same result. I don't know what happened to the cart by just sitting in the box but I wanted to do a visual check inside.

any help is appreciated.

Ray

[sloopy]

Orange or black cart?

Black are glued at the sides, and can be opened so they can be glued again, but not easy...
Orange just come apart with careful prying...

sloopy.

[atari8warez]

sloopy, on Fri Jan 27, 2012 12:47 AM, said:

Orange or black cart?

Black are glued at the sides, and can be opened so they can be glued again, but not easy...
Orange just come apart with careful prying...

sloopy.

It's a black cart, so I guess I need to do some fine cuttin around the edges., hmm.
Thanks sloopy.

[sloopy]

atari8warez, on Fri Jan 27, 2012 12:57 AM, said:

sloopy, on Fri Jan 27, 2012 12:47 AM, said:

Orange or black cart?

Black are glued at the sides, and can be opened so they can be glued again, but not easy...
Orange just come apart with careful prying...

sloopy.

It's a black cart, so I guess I need to do some fine cuttin around the edges., hmm.
Thanks sloopy.

This is what it looks like on the inside:


to give you an idea whats there...
sloopy.

[atari8warez]

Thanks sloopy, I already opened it (had to use a cutting disk with dremel). What's inside is an EPROM 2 capacitors, one resistor, two NOR gates (74ls02) and a flip-flop 74ls74).
I checked the capacitors, the resisitor, contacts and traces, they all seem to be fine, checked the solder joints and they are fine. I even re-seated the EPROM still no go. I am just wondering what could be wrong with the cart. EPROM or one of the other ICs, hmm.

What did you do with that cart on the photo by the way?

Edited by atari8warez, Fri Jan 27, 2012 2:27 AM.

[sloopy]

I took that pic just for you, so I still have it. ;')

it sits here, in the box of carts until i need it...

sloopy.

[Marius1976]

What happens when you only insert the PCB in the Atari? MAKE sure you insert it RIGHT!!!!

My idea is that the Eprom is defect. Selftest comes in... probably a false checksum or a non-working program in Eprom.

When you close your cart again, you could consider fixating the PCB with something. A moving PCB is not good.

[Rybags]

The OS doesn't do checksums against carts - other than for cart change detect when the user hits Reset.

Chances are the system sees the cart and disables Basic but for whatever reason the ROM can't be read.

Don't some OSS carts use a different thickness PCB ? Although I thought it was just the orange ones.

[atari8warez]

sloopy, on Fri Jan 27, 2012 3:13 AM, said:

I took that pic just for you, so I still have it. ;')

it sits here, in the box of carts until i need it...

sloopy.

Oh thanks for the photo but I meant what did you do with those toggle switches. Turning the cart ON or OFF?

[atari8warez]

Marius1976, on Fri Jan 27, 2012 3:25 AM, said:

What happens when you only insert the PCB in the Atari? MAKE sure you insert it RIGHT!!!!

My idea is that the Eprom is defect. Selftest comes in... probably a false checksum or a non-working program in Eprom.

When you close your cart again, you could consider fixating the PCB with something. A moving PCB is not good.

Same thing happens, just goes to self-test screen. I've read that the lifetime for EPROMs is about 25 years. It's been 26 years since I bought that cart, it may have just died on me (bitrot maybe). I also have the BASIC XE which is still fine. I would have prefered to loose that one over MAC/65 though. I can probably get a new EPROM and program it with the MAC/65 image but I am not sure if it's worth the trouble since I already have the .atr version of the ROM.

[Marius1976]

If you want to program with Mac/65 you definitely want the cart in stead of the disk version. The cart version has a few very interesting extra features (like the debugging tool DDT) which the disk version lacks.

I'd say: fix the cart.

[sloopy]

atari8warez, on Fri Jan 27, 2012 3:48 AM, said:

sloopy, on Fri Jan 27, 2012 3:13 AM, said:

I took that pic just for you, so I still have it. ;')

it sits here, in the box of carts until i need it...

sloopy.

Oh thanks for the photo but I meant what did you do with those toggle switches. Turning the cart ON or OFF?

So i dont have to have 4 carts handy... the switches change from BASIC XL - BASIC XE - MAC/65 - ACTION!

sloopy.

[Larry]

Here's a web site you might want to check out.

http://www.retrobits.net/

-Larry

[redman]

This site is also useful.

http://www.pipeline....ardie/roms.html

[atari8warez]

Thank you for the links guys. Great info....Very useful, now if anyone can tell me where can I find a good/cheap (are they mutually exclusive ) EPROM burner..

Edited by atari8warez, Sat Jan 28, 2012 11:20 AM.