Data General Nova 3 and 6045 Drive Questions

[Bruce Ray]

DG Model 6045 disk drive heads 0 and 1 are the removable platter, heads 
2 and 3 are the 'fixed' platter.  As you said, the controller memory 
address and sector/sector/count values are set to 0 by the IORESET 
pulse, so a read operation (STRT pulse) will start the reading of the 
bootstrap into low memory from the removable disk.

Contact me off-list regarding the documentation...

Bruce

On 6/11/2016 10:00 PM, Mark J. Blair wrote:
> My Nova 3/12 system has a 6045 cartridge hard drive, with one fixed platter, one removable platter, and a capacity of 10M. I haven't managed to boot my computer from it yet, and after a long pause, my Nova 3 is requesting another time slice of my attention.
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> I can see in the drive's technical manual where I can specify surface 0-3 in the commands. I assume that the built-in bootstrap loader in the Nova 3 reads drive 0, cylinder 0, surface 0, sector 0, and places it at memory location 0, simply by virtue of all of the registers having been reset after an initial power-up and spin-up. The bootstrap loader code I've seen looks like it just issues a read command without initializing the memory address register and disc address/sector count register. I don't fully grok that code yet, so maybe I'm mistaken.
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> I have not found mention yet of which surface numbers correspond to the fixed platter and which correspond to the removable one. Is the removable platter selected as surfaces 0 and 1, such that the system would normally boot from the removable platter? Or would it normally boot from the fixed platter, with the removable platter being used to get data on and off the system?
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> Incidentally, I wonder if anybody has any original printed technical documentation relevant to my Nova 3 system which they might like to sell. I'm working off PDFs right now, and I'd like clean original paper copies for easier perusal and reference.
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> I'm also interested in replacing the filler panels in my Nova's rack with other interesting peripherals. Maybe a floppy drive? My 6045 is supposed to be able to be mixable with 6030 drives on the same bus, according to the 6045 manual. If anybody has some excess Nova hardware that might fit into my system, please let me know.
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