filbo@gorn.santa-cruz.ca.us (Bela Lubkin) (09/02/89)
[What is this "line-eater"? A bug in some news >sender< or >reader?<]
Hello, net. I've just been fortunate enough to purchase a slightly-used HP
ESDI hard disk -- cheap. The drive is an HP 97536E. It has 12 heads, 1583
cylinders, and 64 256-byte sectors/track [total 311MB]. It is hard-
sectored, which means that the drive will not allow any sector size other
than 256 bytes. This, of course, conflicts with AmigaDOS.
The drive came with an Adaptec 4520A SCSI-to-ESDI controller. As far as I
can tell from the Adaptec documentation, I should have no problem between
the drive and controller. In fact, the behavior of the drive's activity
light, when the combination are powered on, suggests that they do
communicate successfully. The 4520A, by the way, has a mode in which it is
supposed to emulate the behavior of Adaptec 4000-series controllers
(presumably 4000/4070[A]).
I'm attempting to interface the combination to my A1000 through a
SupraDrive 4x4 interface. I'm using version 5.2 of Supra's formatting
software. It doesn't support 256-byte sectors. It does support Adaptec
controllers, but only the 4000 and 4070.
I tried formatting the drive. I could not get anything useful out of
SupraFormat: it invariably responded "This controller does not support the
Mode Select command. Use controller type 'Other'". It supports Mode
Select. My experience with SupraFormat in the past is that if >anything<
is wrong with the format command sequence, it gags with that error message.
In any case, trying to use the "Other" controller, I run into the problem
that SupraFormat insists that sectors are 512 bytes. If I claim 64 sectors
per track, it pretends to start formatting but the drive light never goes
on. If I claim 32 sec/track, allowing the partition table to show correct
sizes, I get the "Other" message. (I may have the two cases reversed). In
all cases I claimed many less tracks than actually exist, as a feasibility
check.
[BTW, has Supra fixed the partitioning requester? Its math is extremely
poor, at least in 5.2; on any fairly large drive, the track numbers and the
sizes it calculates (or vice versa, depending which you enter) do not agree
very well; I end up telling it to leave that last few nonexistent MB free
in order to use up all the tracks].
Would I be able to use this controller with the Supra, if the drive wasn't
limited to 256-byte sectors? That is, is its 40[07]0 emulation good?
Does a later version of the Supra software support 256-byte hard sectors?
(It would probably have to do this by translating AmigaDOS' requests for
single sectors into double physical sectors; I don't see any big difficulty
in this except that someone would have to go to the trouble of implementing
it).
Can AmigaDOS in fact support other sector sizes? (More properly, can OFS
and FFS? Obviously a custom filesystem could, but I'm not up for that at
the moment. ;-)
Finally, if Supra can't do it, are there any other A1000 controllers that
will support such a setup? Transfer rate and other factors would be
important, but getting it to work is primary!
Of course it is by no means a total loss if I can't get it running on the
Amiga -- I could easily hook it up to my PClone -- but what an ignomineous
fate for a nice piece of hardware like this!
Any help would be appreciated. I suspect Thad will come swooping in on
his sleigh and beat off the grinch ... but anyone is welcome.
Mail is fine, but if your reply will be of use to other users, post in the
newsgroup. Move it to .tech if appropriate. [The distinction is not clear
to me, at least by reading messages, which suggests that it's not clear to
readers either. Hmmm?] >Bela<
Bela Lubkin * * filbo@gorn.santa-cruz.ca.us CIS: 73047,1112
@ * * ...ucbvax!ucscc!gorn!filbo ^^^ REALLY slow [months]
R Pentomino * Filbo @ Pyrzqxgl (408) 476-4633 & XBBS (408) 476-4945