jgh@atom.OZ (John G. Haub) (09/12/88)
Home made SCSI Hard disks.
When I started this project I new nothing about how to go about it, I
have since learn't a great deal but obviously not enough to solve all my
problems. I am therefore appealing to the net for a possible solution to my
dilemma.
AIM: To build a home made SCSI hard disk system using 2x20Mb winchesters
(that happened to be lying around) for as cheaply as possible (sound
familiar :-) ).
HARDWARE Macintosh Plus (version 1 ROMS)
USED: Adaptec hard disk controller card model ACB4000-A
2x20Mb Epson winchesters, 5 1/4", ST412/506 interface,4 heads, 614
cylinders (ie. fairly generic).
SOFTWARE System 3.2, Finder 5.3
AVAILABLE:Format, a low level format program by Tim Standing (MacTutor June 87)
SF&I, a SCSI disk formatter and installer by Ephraim M. Vishniac,
version 0.92.
EasyTools, a formatter and installer by D-K research Inc. ver. 2.19
Apples HD SC setup 1.4, 1.5 and 2.0.
PROBLEM: After doing a low level format using 'FORMAT' I was then able to
format and instal the drives using 'SF&I' or 'EASYTOOLS'. Apples 'HD
SC 1.4, 1.5 or 2.0" didn't work (no great surprise). The system works
sort of, in fact I used it to write this. However, the Mac only knows
that one hard disk exists. The Adaptec card has facilities to control
two hard disks but I can only ever access Disk 1. Disk 2 CAN be used
PROVIDED that I configure it as Disk 1 (and likewise Disk 1 as 2).
MY (1) Although I constructed all the cabling myself I am confident
CONCLUSIONS: that no hardware problem exists. As I noted above both drives
have worked, but separately, ie. for the second drive to be used
the jumpers on the winchesters must be changed and the
connnectors for the Drive 1 and 2 data lines must be swapped at
the controller card end. The control lines do not need to be
swapped. I get the impression that the 2nd drive is not
recognised by the formatting program as having a unique address
and therefore can't be accessed.
(2) I am therefore led to believe that I have a software problem. I
think I've heard that phrase somewhere before :-). After much
re-reading of literature (yes I'm running out of ideas) I note
that those people who have made their own SCSI drives tend to
use only one winchester, the author of 'FORMAT' included. Has
anyone controlled two winchesters off the one card? if so please
respond. After examining the code for 'FORMAT' I note that that
the only address that it seems to know about is the SCSI bus
address (in this case '0'). Now I don't know if the drive card
is smart enough to work out that there are two separate drives
and should be able to format both or whether need to tell it
via the low level format program that I am interested in
address 0 Drive 1 or address 0 Drive 2? If so how? I suspect
the latter, my impression is that during low level formatting
the Mac should provide information describing each drive which
the controller card stores on the disk and which is read into
the controllers RAM during power up. From my experience at work
with IBM PC clones the low level format routine does give you
the option of formatting one or more drives. 'FORMAT' doesn't
appear to have this facility. For those people with experience
with the Adaptec ACB4000-A card; does the manual give any clues
as to how a low level formatter should adress both drives and
so enable me to modify 'FORMAT'. When I recieved my card I found
no documentation, a quick call to the agents gave the reply
'That's a separate invoicable item'. I have therefore gone this
far without a manual. At work we find that IBM PC controller
card manuals are generally useless for setting up clones. I
will get a copy of the Adaptec manual if people advise that it
is useful but if it isn't then there's no point.
Any feedback on whether I'm on the right track or any
information on how to get both drives operational would be
appreciated.
-------------------------------------------------------------------------------
John Haub ACSNET: jgh@atom.oz
C.S.I.R.O. ARPANET: jgh%atom.oz@seismo.css.gov
Division of Mineral and Process UUCP: {seismo,ukc,prlb2,ubc-vision}!
Engineering munnari!atom.oz!jgh
Lucas Heights Research Laboratory
Private Mailbag 7 Menai 2234
Sydney
N.S.W.
Australia
-------------------------------------------------------------------------------mpease@cvedc.UUCP (Mark Pease) (09/15/88)
In article <801@atom.OZ> jgh@atom.OZ (John G. Haub) writes: > > Home made SCSI Hard disks. > ... The Adaptec card has facilities to control > two hard disks but I can only ever access Disk 1. Disk 2 CAN be used > PROVIDED that I configure it as Disk 1 (and likewise Disk 1 as 2). > >------------------------------------------------------------------------------->John Haub ACSNET: jgh@atom.oz >C.S.I.R.O. ARPANET: jgh%atom.oz@seismo.css.gov >Division of Mineral and Process UUCP: {seismo,ukc,prlb2,ubc-vision}! >Engineering munnari!atom.oz!jgh >Lucas Heights Research Laboratory >Private Mailbag 7 Menai 2234 >Sydney >N.S.W. >Australia >------------------------------------------------------------------------------- Ahh! The old two Hard Disks on an Adaptec 4000A with a Mac problem!! The problem is not with the software (well, maybe. I have not tried to format two disks with the formaters discribed in the article.) but with the Adaptec! They put out a App. Note that discribes a problem with the Mac/4000A combinations. There is some timing problem (that is OK in the SCSI spec.). The fix is to get a new prom from Adaptec that fixes the problem. I have not tried to run down the prom, has anyone? Mark Pease ..tektronix.csnet!ogcvax.uucp!cvedc!mpease Computervision ..sun.arpa!cvbnet.uucp!cvedc!mpease 14952 N.W. Greenbrier Pkway Beavertion, Oregon 97006 (503)645-2410 -- Mark Pease ..tektronix.csnet!ogcvax.uucp!cvedc!mpease Computervision ..sun.arpa!cvbnet.uucp!cvedc!mpease 14952 N.W. Greenbrier Pkway Beavertion, Oregon 97006 (503)645-2410
tom@iconsys.UUCP (Tom Kimpton) (09/27/88)
>Ahh! The old two Hard Disks on an Adaptec 4000A with a Mac problem!! The >problem is not with the software (well, maybe. I have not tried to format >two disks with the formaters discribed in the article.) but with the >Adaptec! They put out a App. Note that discribes a problem with the Mac/4000A >combinations. There is some timing problem (that is OK in the SCSI spec.). >The fix is to get a new prom from Adaptec that fixes the problem. I have not >tried to run down the prom, has anyone? > >Mark Pease ..tektronix.csnet!ogcvax.uucp!cvedc!mpease >Computervision ..sun.arpa!cvbnet.uucp!cvedc!mpease >14952 N.W. Greenbrier Pkway >Beavertion, Oregon 97006 (503)645-2410 Whoever finds this out, please post their information. Adaptec 4000A owners want to know! Thanks. S t u p i d l i n e c o u n t e r ! -- Tom Kimpton UUCP: {uunet,caeco,nrc-ut}!iconsys!tom Software Development Engineer ARPANET: icon%byuadam.bitnet@cunyvm.cuny.edu Icon International, Inc. BITNET: icon%byuadam.bitnet (multi-user acct) Orem, Utah 84058 PHONE: (801) 225-6888