Looking for a WD 1001 55 Disk controller

From: Richard Erlacher <edick_at_idcomm.com>
Date: Thu Feb 7 18:48:03 2002

I hope nobody gets confused about the interface on this WD board series. The
original and some subsequent posts contain numerous references to SASI, which,
AFAIK, has no relevance to this discussion at all, as the WD-1000-55 and
1001-55 did not use a SASI interface to the host. Some of these boards had a
50-position card-edge connector to the host adapter, of which the ten
conductors at one end were used as supply connections. The 1000-55's that I
currently own are TVI clones of the 1000-55, of which I also had one at one
time, but they use different power connectors than do the standard ones on the
WD1000-55.

Since the SASI host adapter will not have the correct connections, and since
there will be power supply connections at the 50-pin connector, I'd expect to
see major smoke from the controller, the host adapter, and the PSU if one
attempted to hook one of these boards to a SASI or SCSI port.

Dick

----- Original Message -----
From: "Don Maslin" <donm_at_cts.com>
To: <classiccmp_at_classiccmp.org>
Sent: Thursday, February 07, 2002 4:17 PM
Subject: Re: Looking for a WD 1001 55 Disk controller


>
>
> On Thu, 7 Feb 2002, g-wright wrote:
>
> > Hi Dick
> >
> > Sorry for the delay, just had to dig further into this. Brief history,
the
> > Molecular
> > came to me dead in more than one area. I got the main processor going with
a
> > new Counter timer chip. At that point I could not Read or Write to the
hard
> > drives
> > but the Floppy was fine. The WD 1001 SASI to MFM controller was not
seeing or
> > interfacing with the drives. The SASI connection seemed ok. I pulled the
first
> > hard drive and attached it to a PC. It formatted fine with no errors.
HD's are
> > Seagate ST 419 15 meg 5 1/4 Drives. So I replace the cables and looked
into
> > the controlled further. Could not find a true cause of the problem with
the
> > controller.
> > It seemed to not select the drive, nor the head.
> >
> > I finally gave up and robbed one of my other systems of WD 1000 to try.
I did
> > get
> > the Light to come on on the First drive when it booted. I stopped there
and
> > Posted
> > a request for a controller in comp.os.cpm.
> >
> > Did not find one and after many months just setting I decided to Give the
system
> > an-
> > other try. I tried formatting the drives. It just hung there for ever.
I
> > retried this on one
> > of the other drives, still just hung. So I posted to this list. Since I
> > received more that one Email that the other SASI to MFM controllers
should work.
> > I went back and looked
> > further. The hanging was due to the fact that the Heads on the the Drives
where
> > eating the Platters and the controller just could not format the drive.
After
> > putting the Drive back on the PC, the PC Controller had all kinds of
errors. I
> > remove the cover and found the disks are bad.
> >
> > All three drives have the same problems. These are 306 cylinder 6 heads.
I have
> > about 50 Dives but none with this head and cylinder count. So I don't
really
> > know
> > if I really do need the correct controller yet or not. I do need a
seagate ST
> > 419
> > or similar drive though. I still would like a WD 1001 5.5. for 2
reasons. 1 to
> > keep the
> > Molecular original and 2 to help trouble shoot the other controller.
>
> You should know that you can use a different ST-506/411 interface drive
> instead of the failed models provided it has the same or more cylinders
> and heads. You will only be able to utilize the 306/6 capacity unless
> you revise some of the soft(firm?)ware, but it should provide a go/no-go
> test of the controllers.
>
> > For those following this Post. In the earlier days, the SASI interface
was used
> > to interface to these controllers which could control up to 4 MFM drives.
They
> > came in 2 sizes. One would attach directly to a 5 1/4" drive the other
(which
> > I have )
> > was 7" x 10" and could come set up for controlling either 5 1/4 HD's or
8"
> > hard drives.
> > I don't know what real code differences there are between the controllers.
There
> > is
> > a different clock and interface for the 8" hard drives. The chips used and
the
> > layout is
> > quit different between the different boards.
> >
> > SASI is the early version of SCSI. It had most of the same signals and
has a 50
> > pin connector.
> >
> > One big difference is what all the pins where used for. The one here has
the
> > power and
> > ground for the WD 1001 card supplied though the cable. Others have a
separate
> > power connector.
> >
> > For those that though I needed a PC ISA card. I guess they just used the
next
> > number
> > in line when the made the WD 1002 xxx ISA bus to MFM controller.
>
> There is also a WD-1002 bridge controller in 5.25" drive size. It was
> used in the Kaypro-10, amongst other machines.
>
> - don
>
> > What is a Molecular?? It is a Z-80 basic multi user system. It had 1)
Z-80
> > computer that controlled the Disk system and 4 to 10 slave cards that each
user
> > was connected to through
> > a dumb terminal. OS is CPM and Nstar.
> >
> >
> > Thanks, again
> > Jerry
> >
> > Jerry Wright
> > JLC inc.
> > g-wright_at_worldnet.att.net
> >
> > Richard Erlacher wrote:
> >
> > > What differences does your system rely on? I once had WD1000, 1001, and
1002
> > > boards, all interchangeable in the TVI TS-806. I do recall there were
> > > differences, but I don't recall how they might impact you.
> > >
> > > regards,
> > >
> > > Dick
> > >
> > > ----- Original Message -----
> > > From: "g-wright" <g-wright_at_worldnet.att.net>
> > > To: <classiccmp_at_classiccmp.org>
> > > Sent: Wednesday, January 30, 2002 3:54 PM
> > > Subject: Looking for a WD 1001 55 Disk controller
> > >
> > > > Hi
> > > >
> > > > I'm trying to get a Molecular going. it has Bad disk controller. WD
> > > > 1001 55
> > > >
> > > > Does anyone have one of theses that they can spare.
> > > >
> > > > I have 1000 series But there is a difference.
> > > >
> > > > E-mail me at address below
> > > >
> > > > Thanks, Jerry
> > > >
> > > > Jerry Wright
> > > > JLC inc.
> > > > g-wright_at_worldnet.att.net (new)
> > > >
> > > >
> >
> >
>
>
Received on Thu Feb 07 2002 - 18:48:03 GMT