17 replies to this topic

[Wickeycolumbus]

I recently won this proto in an auction, it has a production label pasted over a loaner label (and a sticker that says "EPROM"). It is only one byte different from the final version. Here is the ROM and scans of the cart.

Attached Files

•  Defender EPROM .bin   4K   128 downloads

Edited by Wickeycolumbus, Thu Aug 20, 2009 3:21 PM.

[Nukey Shay]

But is it a proto? There is actually only one bit that is different...causing what is supposed to be a CMP# opcode ($C9) at $F0F7 to be an illegal double-NOP opcode ($89). IMO it's more likely that this bit had been stripped when dumping the commercial cart to be burned to eprom.

[Wickeycolumbus]

It is definitely a proto, here is a pic of the PCB. Bob Polaro confirmed it's authenticity, and it had no screw in it.

Attached Thumbnails

• 

[Tempest]

I've seen similar things before in 5200 protos (production labels on lab labels). My best guess is that these were final review copies and they slapped a production label on them when they became available. I've seen protos with box artwork on them before as well.

Tempest

[Rom Hunter]

Wickeycolumbus, on Thu Aug 20, 2009 3:15 PM, said:

I recently won this proto in an auction, it has a production label pasted over a loaner label (and a sticker that says "EPROM"). It is only one byte different from the final version. Here is the ROM and scans of the cart.

main.png
End.png

Interesting.

Thanks for sharing, wicky!

Edited by Rom Hunter, Sat Aug 22, 2009 12:26 AM.

[Rom Hunter]

So, should I add this one to the collection or not?

[Omegamatrix]

Rom Hunter, on Mon Oct 12, 2009 2:13 AM, said:

So, should I add this one to the collection or not?

Rom, Nukey's logic is sound. This proto is the final version, but has suffered damage either from bit rot, or when it was getting burned. It's not the case that it was a bad dump, but that rom is slightly corrupted.


The old era roms didn't use illegal opcodes. IMHO I'd leave this out. It most certainly was/is the released version sans a bit of bit corruption.

[Rom Hunter]

So be it.

Not added.

[david.winter]

Rom Hunter, on Mon Oct 12, 2009 3:02 AM, said:

So be it.

Not added.

I have to veridy but I too happened to find a similar cartridge. The board is different, as it uses a single 2732 eprom and one inverter to enable the chip. The board looks hand cut on the sides to accomodate to the cartridge case, however the eprom is soldered so I can't read it without a connector. I'll post a picture later when I'm back from work.

[david.winter]

I checked my board (picture below) and this is also Defender.
The eprom is soldered so I don't know whether it's worth dumping it.

Attached Thumbnails

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[Bruce Tomlin]

I can say one thing about the board in that photo... it's no one-off hobbyist or prototype board. It's clearly designed for mass-manufacture with its snap-apart edges. Are there any part numbers on it?

The dates on the chips indicate that it is no older than mid-'82. I see the release date as September 1981, so if it's Defender, it's not a "prototype" as in pre-release. And Atari (AFAIK) wouldn't have used an EPROM, especially post-release.

[Wickeycolumbus]

david.winter, on Mon Oct 12, 2009 10:04 AM, said:

I checked my board (picture below) and this is also Defender.
The eprom is soldered so I don't know whether it's worth dumping it.

That sure is a strange looking PCB Does the cartridge look like an ordinary Defender cartridge?

[david.winter]

This pcb has no part number and was in an ordinary Atari Defender cartidge.
I can only imagine that Atari may have had a delay in getting mask ROMs and used this alternate solution.
The edges really look like they were drilled to fit in the cartridge case. This really doesn't look like a mass production; This looks more like a manual finnish.

David

[horseboy]

david.winter, on Wed Oct 14, 2009 1:25 AM, said:

The edges really look like they were drilled to fit in the cartridge case. This really doesn't look like a mass production; This looks more like a manual finnish.

David

Many PCBs are mass produced this way. The holes are there to make them snap apart easily.

[david.winter]

horseboy, on Wed Oct 14, 2009 10:33 AM, said:

Many PCBs are mass produced this way. The holes are there to make them snap apart easily.

That was not common at Atari. Of all the usual cartridges that I salvaged to remove the pcb and use the case for Rubik's Cube 3D, only one had an eprom. All others had mask programmed ROMs. One or two even had a "bundle" chip.

[Shawn Sr.]

This board is legit, I found one myself last year also. At that time it was presumed by the masses to be a fake of some sort but now that you also have found one of these exact same "hand carved notches" boards this verifies it's the real deal. There is no mention of the word atari anywhere on the board also correct? Mine didn't have atari on it anywhere. Mine came out of a video olympics labeled shell but the game was defender inside, also with no screw as you found with yours.

Edited by Shawn Sr., Sat Oct 17, 2009 3:21 PM.

[Bruce Tomlin]

"Real" in what way? No way would Atari have made a board like that with an EPROM, months after the game's release. They never missed an opportunity to monopolize mask ROM production to bring down per-chip prices and put the squeeze on competitors. (That's part of the reason they had to bury so many ET carts.)

But it was clearly a professional mass-production design, with snap-apart gold-contact circuit boards and (apparently) wave soldering. (note that boards like that can be separated after assembly and soldering!)

Someone must have been making relatively large quantities (thousands) of those... maybe it was from a high-volume pirate operation? I really don't know what to think.

[Shawn Sr.]

Bruce Tomlin, on Sat Oct 17, 2009 6:56 PM, said:

"Real" in what way? No way would Atari have made a board like that with an EPROM, months after the game's release. They never missed an opportunity to monopolize mask ROM production to bring down per-chip prices and put the squeeze on competitors. (That's part of the reason they had to bury so many ET carts.)

But it was clearly a professional mass-production design, with snap-apart gold-contact circuit boards and (apparently) wave soldering. (note that boards like that can be separated after assembly and soldering!)

Someone must have been making relatively large quantities (thousands) of those... maybe it was from a high-volume pirate operation? I really don't know what to think.

Real as in I belive it really came out of an atari factory sold cartridge cause I've pulled the same myself. I showed it to CPU and Tempest last year and they dismissed it as a pirate but I really think there is more to it at this point. In house demo, magazine editor freebee or something.

Edited by Shawn Sr., Sat Oct 17, 2009 9:09 PM.