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DrVenkman

Interesting find inside one of my 400's

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... subtitled, "Why You Should Always Disassemble Your eBay Purchases"

 

I bought this 400 on eBay at least 11 or 12 years ago. It came with a couple joysticks and a few carts. My wife and I played PAC MAN and ASTEROIDS with it on and off for a few months and after a year or so it went back into storage as I bought other systems and added to the A8 collection. Last Christmas, one of my oldest friends surprised me with a second complete-in-box "The Basic Computer" 400 system, and a full Programmers Pack with a never-used 410. So today, with time to kill, I decided to take both 400's apart for a good internal inspection and cleaning. The newer (to me) 400 has never been touched inside before - it was almost as clean as the day it left Sunnyvale in August 1982. The other one, the one I got on eBay so long ago, was a Hong Kong-made unit that, inside, was a mess. Filthy with dust and decades-old nicotine residue, it took some work to get cleaned up. But in so doing, I found an intriguing little surprise.

 

Under the bottom RF shield, I see some sort of hackery ...

 

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Where the wires are routed around to the top of the motherboard, I see a small "dead bug" IC glued to the board and jumped in several places.

 

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Examining the personality and RAM boards reveals more hackery afoot!

 

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Yes, this little thing has a hacked-in 48K upgrade mounted on the original Atari 16K board. I've had this thing for over a decade and never even thought to check the memory capacity. So here's something you rarely if ever saw back in the day, and probably see even more rarely today: a 1982 Atari 400 running a pair of floppy drives.

 

post-30400-0-67646300-1406937242_thumb.jpg

 

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Awesome! I was hoping someone here would recognize the fell digital sorcery involved and tell me more about it! :D

 

I can't get over how funny (ironic really, not humorous) it is that I've had this for so long and never even thought it was anything more than a run-of-the-mill 16K 400. I don't know if I've ever even had a BASIC cartridge inside it until today.

Edited by DrVenkman

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I had the same find with a 1200XL I purchased over 10 years ago. I never used it, and finally got it out to see what's up. It wouldn't start, so I opened it up to reset the chips and found out it had a Newell 256K upgrade. Very nice.... Wish the previous owner had done the video mod too, but I guess I can't be too choosy, lol!

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is there one like this for the 800?

 

There were the Byrd & Windhover upgrades for the 800, which modified a 16K card to 256K, but they weren't supposed to be 100% compatible with the commercial Axlon/Magna memory cards. They were supposed to work as RAM-disks, but wouldn't necessarily work with software supporting Axlon/Magna extended memory.

 

The attached ZIP file contains both the 400 64K and 800 256K Windhover upgrade instructions.

Windhover-400-800.zip

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The Windhover 400 upgrade is a complete rip-off of the one I did for MACE in 1982. He claims MACE ripped him off in 1979. Was MACE even around then?

 

Their 800 upgrade may be a rip-off of the Byrd mod, I'm not sure. I talked to Byrd on the phone in 1985 and he seemed like a good guy. Whereas Torres claims he got his 16K 800 in 1978. Right.

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Well I don't know anything about that, but I'm glad your development made its way into my little 400. This particular upgrade on mine looks like it uses Hitachi 4864-2 64kb DRAMS, so I guess it's 64K board. With the memory required for the OS ROMS and housekeeping, how much does that leave usable to programs under the usual Atari OS/B? Around 52K or so?

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