[Coco] B&B HD Setup

[Gene Heskett]

On Sunday 03 May 2009, tonym wrote:
>How long should the physical+logical format take?

Physical+logical is maybe 2 or 3 minutes because there is no physical on a 
hard drive, even one that old.  Logical consists of writing LNS0, then the FAT 
which is however much of 64kb the number of sectors available on the disk is 
divided by 8 since one bit is a sector for that sized drive, and the root 
directories file descriptor sector, and the root directory itself.  This is a 
very quick process and the ramddisk 'myram' actually does this in the few 
milliseconds lag between requesting an access to it with a "dir /r0" before it 
shows the empty directory to you.  The click click is the verify phase, where 
it verifies every sector on the disk, and any bad sectors are marked in the 
FATable as used.  That takes a while.  And the drive has to go back and write 
the next sector of the FAT each time it has verified 256*8 sectors, or 2048 of 
them, and that represents 524,288 bytes of disk.  That is a 42meg disk, so it 
will do that at least 84 times.  Those will be double-clicks when it does 
that, the regular ones are just the next track seeks.

dcheck won't like that if there are some that fail the read check, so when I 
was using a 30 meg seagate RLL drive, I used dEd to create, byte by byte, a 
file whose file descriptor sector accounted for all those bad sectors.  But be 
sure and use a good sector for the file descriptor. :)  And the limiting 
FD.SEG count is 48, so if there are more bad sectors than that, you'll need to 
create additional files for.  Name them dcheck-bad-sectors-0, dcheck-bad-
sectors-1 or something similar to remind you to never delete them.

>It's been going since like 2am! I can still hear the click..click...click

On a 42 megger, on a B&B, it should be about done by now.  On my 130 meg 
Maxtor, it was a bit over 30 hours AIR, but the disto interface I used with 
the maxtor is over 2x faster than the B&B.  13 secs for a megaread... I think, 
heck, that was about 20 years ago, on a coco2!

>Drive is a 42M IBM 0665-53 733cyl 7hd box-stock L2 with the B&B drivers...

You will want to replace that with Nitros9 of course, its faster. :)

>
>Tony
>
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-- 
Cheers, Gene
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