Post by Cube Inc. on Dec 29, 2022 10:50:44 GMT -7
I have finally reached the point of regret in my decision over a decade ago to part with my 8250 and two SFD-1001 IEEE drives, along with the two Buscard ][ IEEE interfaces I had for the Commodore 64.
As you may or may not know, the 8250 was a dual drive built for the Commodore PET line of computers, and as such it utilized the much faster (*than the stock IEC serial interface found on VIC-20 and C64/128 line of computers) IEEE-488 parallel interface. As a dual disk mechanism, it also gave the computer access to two floppy disks worth of storage at a single time (without having to manually swap disks, etc.) and both of those disks were formatted in such a way that they could hold 4133 Commodore Blocks of space, equating to 1MB of storage! That is in contrast to the 664 blocks the Commodore 1541 held using the very same standard Double Sided, Double Density 5 1/4" floppy disks. In fact, the 8250 could not format or use the more expensive High Density disks which were necessary to eek out 1.2MB of storage on the IBM side of the fence. The 8250 also had its own processor, ram and built in Disk Operating System, similar to a 1541 in that it could be programmed to perform tasks independently of the computer(s) it was connected to such as copying one disk to the other. All in all, a remarkable piece of technology, and one I now regret having parted with.
The SFD-1001 was essentially a single drive version of the 8250 in a 1541 case. It still utilized the high capacity formatting method used by the 8250 and disks formatted in one were reliably readable and writable by the other. Of course it could not do disk-to-disk copying on its own without a second SFD-1001 or an 8250 chained to it.
The IEEE-488 parallel port was also interesting because you could daisy-chain multiple drives together, similar to how we do with the 1541/71/81 series of drives. The PET drives also allowed usage of higher drive numbers and could be hardware configured for any address from 8 to 15. At one time I had a 2040, a 4040, an 8050, an 8250, two SFD-1001's, a 2031, a SFD-1001 and a Daisy Wheel printer all connected on the same ribbon cable that I made from parts purchased at the local electronic store. Ahh, nostalgia!
If anyone has one of these drives, and or a Buscard ][ IEEE interface that they would be willing to part with, please let me know and we will work out a deal.
Thanks,
