Challenger 2 OEM out of mothballs

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Greetings,

Someone contacted me about buying my OSI system, so I figured I'd better get it out of storage and see if it still works. Amazingly, it does. A Dinosaur roams the earth! And the Starship Enterprise is in need of a new captain...

While I have it open, I took inventory of the key components. I've had this system since roughly 1980-81. It's build date is 1/10/1980.

2 Shugart 801 floppy disk drives, 8" single sided. Floppies can be flipped over and the back side used as well.

OSI 505 B CPU card, 6502 cpu, 6820 PIA, floppy and RS232 interfaces. 2 open 40-pin sockets for ROM, or another PIA.

OSI 470 B configured for the NEC Spinwriter

2 OSI 520 B static RAM cards, 16K each

OSI 530 DRAM card, another 16K

3 power supplies provide 5V, -9V, 12V and 24V DC. There is a second 5V supply, possibly just for the DRAM.

Mods: The 470 card came set up for Centronics, IIRC. I modded it back in the day for an NEC Spinwriter. I had to patch the OS to jump to some additional code to spoon feed the NEC, which has a very low level interface. Basically, I wrote a printer driver in Hex and POKE'd it into memory, then inserted a jump and return in the main code. I put a 50 pin connector on the back for a ribbon cable to the NEC.

Just now, I made a change for maintainability. I flipped two of the power supplies around so the guts face outward. The screws were originally put in there with some kind of glue on them that required vice grips, grrr. I replaced all the power supply mounting screws.

[mediasponge]

Star Trek in BASIC

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C2

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C2

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