OBRIEN%OBRIEN@VENUS.YCC.YALE.EDU ("James A. O'Brien 432-4382", 203) (11/27/88)
I hope someone can help me with this. I originally had a Seagate ST506
5MB drive in my Rainbow - I replaced it with a 20MB ST225 a couple of years
ago. My wife has a PC clone and we thought it would be neat to put even
a 5MB drive in it. So, I bought a Western Digital disk controller for $70
mail order, and connected the whole thing up. I had all the drive parameters
(153 cylinders, 4 heads, etc) and fed them to the WD formatter (it's in
BIOS on the WD board accessed through DEBUG). The drive made clunking and
stepping noises, which SOUNDED like it was formatting, but it wasn't in
reality - the program ends with a "nothing done exit". Now, when I tried
to run FDISK anyway, I noticed that selecting either fixed disk 1 or fixed
disk 2 caused my 5MB drive to respond. My deduction from the above is that
I need to install some kind of jumper on the drive to perform a correct
"drive select". Of course, I have no technical documentation for the ST506!
Can someone point me in the right direction on this problem? Any assistance
will be much appreciated. For example, is a 5MB ST506 which was originally
in a Rainbow different from a "generic" ST506? (i.e. did DEC modify it, aside
from testing it to comply with their more stringent quality control standards?)
Again, in summary, I'm trying to make my old Rainbow ST506 drive work with
a WD hard disk controller in a PC/XT clone.
Jim O'Brien
Department of Chemical Engineering
Yale University
2159 Yale Station
New Haven, CT 06520, U.S.A.
+1 203 432 4382 (days)
+1 203 322 7222 (eves)
Return Addresses (both equivalent):
OBRIEN%OBRIEN@YALEVMS BITNET
OBRIEN%OBRIEN@VENUS.YCC.YALE.EDU Internet
|--+-| |--+-| |-------+--------|
| | |
| | +--------| host network address
| +--------| microvax node name
+---------| userid on microvax bcw@rti.UUCP (Bruce Wright) (11/27/88)
In article <Added.QXXkSyy00Ui3I9ek9H@andrew.cmu.edu>, OBRIEN%OBRIEN@VENUS.YCC.YALE.EDU ("James A. O'Brien 432-4382", 203) writes: > I hope someone can help me with this. I originally had a Seagate ST506 > 5MB drive in my Rainbow - I replaced it with a 20MB ST225 a couple of years > ago. My wife has a PC clone and we thought it would be neat to put even > a 5MB drive in it. So, I bought a Western Digital disk controller for $70 > mail order, and connected the whole thing up. I had all the drive parameters > (153 cylinders, 4 heads, etc) and fed them to the WD formatter (it's in > BIOS on the WD board accessed through DEBUG). The drive made clunking and > stepping noises, which SOUNDED like it was formatting, but it wasn't in > reality - the program ends with a "nothing done exit". Now, when I tried > to run FDISK anyway, I noticed that selecting either fixed disk 1 or fixed > disk 2 caused my 5MB drive to respond. My deduction from the above is that > I need to install some kind of jumper on the drive to perform a correct > "drive select". Of course, I have no technical documentation for the ST506! > I'm not sure what your problem is, exactly, but I can make some guesses. First of all, the ST506 that DEC sold for the Rainbow is for all practical purposes an unmodified ST506 (they did do a fair amount of culling to get the best drives in the lot). And the standard PC interface, at least for XT-class machines, is an "ST506 interface" - because that was the original drive to use it! You shouldn't need to modify any straps or anything on the drive to make it run on an PC clone. You will need to get the cables right ... this can be a bit confusing if you haven't done it much (especially since there are several different kinds of cable configurations for PC clones, and if you hook things up the wrong way all sorts of things could go wrong). Your problem _sounds_ like a typical cable problem (but may not be ...). I don't know what Western Digital controller you have. WD makes a _lot_ of disk controllers and they are not interchangeable!! Some of them have all sorts of "features" on them, are combined hard/floppy controllers, RLL controllers, etc, etc. Also the BIOS on the controller has gone through a number of revisions and some of the versions are, of course, better than others (and the better versions are not always the most recent). It is possible that the controller/BIOS you have just can't accept the particular drive parameters for the 506. Finally, be aware that the 506 is a much slower drive than the more recent drives (something like a 95 ms average seek time). Some controllers/BIOSs may not like that - and time out on a perfectly valid (and successful) operation! It really is critical to know what the controller and BIOS version are to know if this might be a problem. Good luck! Bruce C. Wright
campbell@redsox.UUCP (Larry Campbell) (11/28/88)
In article <2594@rti.UUCP> bcw@rti.UUCP (Bruce Wright) writes: } }Finally, be aware that the 506 is a much slower drive than the more recent }drives (something like a 95 ms average seek time). Some controllers/BIOSs }may not like that - and time out on a perfectly valid (and successful) }operation! It really is critical to know what the controller and BIOS }version are to know if this might be a problem. No, it's even worse than that. The ST506 has a 170ms average access time!! Almost as slow as a floppy! What's worse, it does not buffer step pulses. Since nearly all drives today buffer step pulses, it could be that the controller you have doesn't work with unbuffered drives. I think your best bet is to trash the ST506 and cough up $200 for an ST225 or similar drive. -- Larry Campbell The Boston Software Works, Inc. campbell@bsw.com 120 Fulton Street wjh12!redsox!campbell Boston, MA 02146