While I've never seen this error and assuming you have access to an Adaptec SCSI controller on a PC, you COULD try to low level format it from within the Adaptec BIOS. It's risky..but at this point you don't care. A controller-issyued low level format will basically reset the block defect list and perform a surface scan, layout tracking marks, and mark bad blocks again. Assuming this isn't a larger symptoms, you could basically attempt to format for bad blocks. However your disk must start normally to do this.
It will either work and exploded, at this point I guess either is acceptable?
Update 1: By the way, manpage claims FORmat shouldn't be done on a hard or fixed disk. It's possible format meant low-level format? A partial or bad low-level format can corrupt fixed disk media if not done 100% correctly.
https://nixdoc.net/man-pages/IRIX/man1/fx.1.html
UPDATE 2 : This confirms it, format MEANS low-level format! In SCSI parlance, destroying the bad block, track layouts, etc... list implies a low-level format.
http://retrogeeks.org/sgi_bookshelves/SG...674-PARENT
OK, from your description, I'm confused...you did inadvertently issue a low-level format. However when you say "locked up the machone", how did you observe this and did you shutdown during the operation? Low-level format are done by drive firmware...not the SCSI controller. The controller issues the command then just waits. It's totally normal for nothing to appears on the screen until it's done...like hours! There are no progress bars and may not be any updates on progress until complete.
So if you can describe what you saw you can help others, but you interrupted a low-level format and power-cycled the drive...if that's what you did...then your disk format on disc platters is ruined, period. Tracking markings for the drive head and info were being rewritten when you interrupted it, most drives cannot recover from this as it's done at the factory initially and in the field uses an in-memory info of what they looked like during boot during the reformat. Rebooting removed that info from drive ram and the format didn't complete so it's not on the disk anymore during boot. It's no bricked.
It's gone, you've learned an expensive lesson...FX meant low-level format...yeah they labelled it wrong. But that's what happened, you have a partially formatted disc track layout now, your drive head won't be able to track on disk anymore.
I've done exactly 6 low-level formats in my life. One for bad block rescanning and 5 to change RAIDed SCSI Drives from 520 byte block to 512 byte block (via linux sg-tools). It was nail biting, but I knew I was doing it and even used a UPS. I can't stand FX, I say auto - root or option drive and that's it. So I've never dared press any other option.
NEED -> 
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