Getting a Sider hard drive working (question from another site)

Post by Nick Westgate
Hi guys.
Someone had this question, and although I found some info from old CSA2
posts I thought I'd check if anyone knows any more. For instance how
many Xebec controller cards where there, and did they just differ in
firmware?
"What should I look for in a controller card? I've read that the Sider
was SASI (the forerunner of SCSI) and that the RamFAST card by
Sequential Systems would be a good choice for a controller (assuming I
can find one). I've also read that Apple produced a SCSI controller for
the //e and //gs but I am uncertain if that card would work with a SASI
drive (assuming the drive is SASI)."
http://retrocomputing.stackexchange.com/questions/1582/how-to-connect-an
-apple-iie-to-an-external-sider-hard-disk-drive
Cheers,
Nick.

Hi Nick,

Just incase you're still interested in this year old inquiry:

The only difference between (FCP SIDER) SASI and (APPLE) SCSI that I could determine (back in the day when Apple adopted SCSI) was that the Data Bus lines [D0~D8] (output from the SASI interface card, input to the FCP SIDER HDD, e.g., the cable) were inverted polarities and all other address/signal polarities were the same. I determined this by comparing the SIDER schematics, and pin-outs, and all the documentation I could find about SASI (from Shugart Associates), with the corresponding SCSI (1.0/1.1?) Standard schematics, and pin-outs, and all the documentation I could find about SCSI.

The other thing about Terminal Power from GEO...s original webpage is also important. I think there was a switch on the interface card or jumper block on the back of the HDD that allowed it to be switched on or off.

Yours truly,

James Davis

Steven Hirsch

2017-10-08 16:25:13 UTC

Post by James Davis
Hi Nick,
The only difference between (FCP SIDER) SASI and (APPLE) SCSI that I could
determine (back in the day when Apple adopted SCSI) was that the Data Bus
lines [D0~D8] (output from the SASI interface card, input to the FCP SIDER
HDD, e.g., the cable) were inverted polarities and all other address/signal
polarities were the same. I determined this by comparing the SIDER
schematics, and pin-outs, and all the documentation I could find about SASI
(from Shugart Associates), with the corresponding SCSI (1.0/1.1?) Standard
schematics, and pin-outs, and all the documentation I could find about
SCSI.

I don't think that's correct. The original RamFAST card worked properly with
both SCSI and SASI drives. That would hardly have been the case if signal
polarity was inverted.

There probably were differences between SASI and SCSI with regard to minimum
required feature sets and control block definitions. But basic signaling? I
doubt it.

Steven Hirsch

2017-10-08 17:53:23 UTC

I don't think that's correct. The original RamFAST card worked properly with
both SCSI and SASI drives. That would hardly have been the case if signal
polarity was inverted.
There probably were differences between SASI and SCSI with regard to minimum
required feature sets and control block definitions. But basic signaling? I
doubt it.

Another bit of evidence to the contrary: "Back in the day" I routinely used a
Sider / Xebec Apple 2 host adapter to communicate with SCSI drives.

James Davis

2017-10-09 01:50:36 UTC

I don't think that's correct. The original RamFAST card worked properly with
both SCSI and SASI drives. That would hardly have been the case if signal
polarity was inverted.
There probably were differences between SASI and SCSI with regard to minimum
required feature sets and control block definitions. But basic signaling? I
doubt it.

Another bit of evidence to the contrary: "Back in the day" I routinely used a
Sider / Xebec Apple 2 host adapter to communicate with SCSI drives.

Hi Steven,

Well, all I can say is that according to the documentation that came with my FCP SIDER, its SASI interface Data Bus lines, compared with all the corresponding documentation I could find about SCSI, indicates they are inverted signal polarities. I never tested it though, with a multi-meter or any other SCSI drives/devices. I always wondered if it would work with SCSI drives/devices, but was never willing to try it out, after making my determination. I thought about making an inverter board, but never did. I did not want to fry anything.

I still have every Apple II related thing I ever bought or created (except that my original Apple II Plus and all the Lower Case Adapters I had have been sold; and, I shredded the source code for my AppleWorks TimeOut Ultramacros Disassembler a few years back, I think!). So, if you would like me to scan and send you copies of the pertinent documents, I will. Just reply privately to this if you want them.

I could have been mistaken, but I didn't think SASI and SCSI were identical at the time, IIRC!

Sincerely yours,

James Davis

P.S. I always wondered what kind of internal connection to the actual HDD inside the SIDER is. Do you know? Is it EIDE?

Steven Hirsch

2017-10-09 11:43:05 UTC

Post by James Davis
Well, all I can say is that according to the documentation that came with
my FCP SIDER, its SASI interface Data Bus lines, compared with all the
corresponding documentation I could find about SCSI, indicates they are
inverted signal polarities. I never tested it though, with a multi-meter
or any other SCSI drives/devices. I always wondered if it would work with
SCSI drives/devices, but was never willing to try it out, after making my
determination. I thought about making an inverter board, but never did. I
did not want to fry anything.

You can definitely talk to standard SCSI devices with the Xebec host adapter
card. Software is a different story and it's not a given that the Sider
software will work.

Post by James Davis
I still have every Apple II related thing I ever bought or created (except
that my original Apple II Plus and all the Lower Case Adapters I had have
been sold; and, I shredded the source code for my AppleWorks TimeOut
Ultramacros Disassembler a few years back, I think!). So, if you would
like me to scan and send you copies of the pertinent documents, I will.
Just reply privately to this if you want them.
I could have been mistaken, but I didn't think SASI and SCSI were identical
at the time, IIRC!

They are not identical, but the electrical signaling is compatible.

Post by James Davis
P.S. I always wondered what kind of internal connection to the actual HDD
inside the SIDER is. Do you know? Is it EIDE?

Yes. The Sider branded drives used a proprietary Xebec disk unit with
built-in SASI interface. The older (and larger) units sold under the Datamac
and Trustor brand names had a Xebec 1410 "bridge" controller that converted
the SASI bus to MFM. These used a variety of drives from other manufacturers.

James Davis

2017-10-10 00:27:22 UTC

Post by Steven Hirsch
You can definitely talk to standard SCSI devices with the Xebec host adapter
card. Software is a different story and it's not a given that the Sider
software will work.
. . .
They are not identical, but the electrical signaling is compatible.

I wonder if a PC could be hooked up on the opposite end of the Apple-SASI/Sider/~/SCSI-PC chain and used to read the data off the Sider?

Post by James Davis
P.S. I always wondered what kind of internal connection to the actual HDD
inside the SIDER is. Do you know? Is it EIDE?

So, it is not EIDE then?!

James Davis

2017-10-10 00:30:37 UTC

Post by James Davis
I wonder if a PC could be hooked up on the opposite end of the Apple-SASI/Sider/~/SCSI-PC chain and used to read the data off the Sider?

Maybe with the AppleWin emulator or a GS emulator?

mrbrad

2017-10-10 11:39:23 UTC

I wonder if a PC could be hooked up on the opposite end of the Apple-SASI/Sider/~/SCSI-PC chain and used to read the data off the Sider?

Post by James Davis
P.S. I always wondered what kind of internal connection to the actual HDD
inside the SIDER is. Do you know? Is it EIDE?

So, it is not EIDE then?!

The sider's I have are mfm drives ..i forget which seagate 20mb or 10mb
ones I think....st-??

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Brian Patrie

2017-10-12 06:27:34 UTC

Post by mrbrad

Post by Steven Hirsch
The Sider branded drives used a proprietary Xebec disk unit with
built-in SASI interface. The older (and larger) units sold under the
Datamac and Trustor brand names had a Xebec 1410 "bridge" controller
that converted the SASI bus to MFM. These used a variety of drives
from other manufacturers.

So, it is not EIDE then?!

The sider's I have are mfm drives ..i forget which seagate 20mb or 10mb
ones I think....st-??

Mine is a Xebec 4020 (SASI).

mrbrad

2017-10-12 13:49:41 UTC

Post by Brian Patrie

Post by mrbrad

Post by Steven Hirsch
The Sider branded drives used a proprietary Xebec disk unit with
built-in SASI interface. The older (and larger) units sold under
the Datamac and Trustor brand names had a Xebec 1410 "bridge"
controller that converted the SASI bus to MFM. These used a variety
of drives
from other manufacturers.

So, it is not EIDE then?!

The sider's I have are mfm drives ..i forget which seagate 20mb or
10mb ones I think....st-??

Mine is a Xebec 4020 (SASI).

Again if I remember right the HD is mfm ...the controller on is is
sasi...thus if you ever replace the HD and use the controller I heard
that you needed to format the HD first with a xebec on an IBM with the
xebec Ibm controller ..then you could format using sider utils at that point

I could be dead wrong on this .did not have to ever replace a hd in this
manner...and this could be for the old xebec data mac's or sider 10mb

but for whatever reason it stuck in my head

others likely on here will probably know more

brad
former sysop lost gonzo bbs

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Steven Hirsch

2017-10-13 15:47:13 UTC

Post by Brian Patrie

Post by mrbrad

Post by Steven Hirsch
The Sider branded drives used a proprietary Xebec disk unit with
built-in SASI interface. The older (and larger) units sold under the
Datamac and Trustor brand names had a Xebec 1410 "bridge" controller that
converted the SASI bus to MFM. These used a variety of drives
from other manufacturers.

So, it is not EIDE then?!

The sider's I have are mfm drives ..i forget which seagate 20mb or 10mb
ones I think....st-??

Mine is a Xebec 4020 (SASI).

That's what was in my Sider.

Only the older, non-Sider branded drives (sold as Datamac, Trustor and a few
other brand names) were MFM + bridge controller. The Sider had very little
room inside and every one I've seen had a Xebec drive with integrated SASI bus.

Steven Hirsch

2017-10-10 11:53:56 UTC

Post by James Davis
P.S. I always wondered what kind of internal connection to the actual HDD
inside the SIDER is. Do you know? Is it EIDE?

So, it is not EIDE then?!

No, it predates IDE by ten years or more. Originally they bridged to a
standard (for early 80s) MFM drive. Later on they developed their own drive
with an integrated SASI interface. I think it was the Xebec "Owl" drive.

James Davis

2017-11-01 08:10:22 UTC

"Back in the day" I routinely used a Sider / Xebec Apple 2 host adapter to communicate with SCSI drives.

Hi Steven,

Do you think the "SCSI2SD" card will work with or on the end of (terminating) an FCP Sider SASI chain (using the Sider Apple 2 host adapter)?

Could one be used to first duplicate and then replace a Sider HDD?

James Davis

Steven Hirsch

2017-11-01 12:01:12 UTC

"Back in the day" I routinely used a Sider / Xebec Apple 2 host adapter
to communicate with SCSI drives.

Do you think the "SCSI2SD" card will work with or on the end of
(terminating) an FCP Sider SASI chain (using the Sider Apple 2 host
adapter)?
Could one be used to first duplicate and then replace a Sider HDD?

That's questionable, since the FCP driver is written for SASI. There are some
minor behavioral differences with regard to bus timing and phase changes. I
think you'd just have to try it and see.

James Davis

2017-11-02 00:25:45 UTC