2 Dec
2018
2 Dec
'18
1 p.m.
Hi folks,
In my long ongoing quest to image and otherwise copy the hard sectored floppies with my
Exidy Sorcerer I?m trying to find other floppy drives I can use with it since I don?t like
relying on just one set of drives. I have a Cumana dual drive set that came with my TRS80
Model1 that I thought might be jumperable to 300rpm, indeed I can see drive activity if I
try and boot.
Does anyone know where I might find the/a manual for the drives? They?re marked as
Intertec 5002040 so I?ve been all over Superbrain docs and PDFs on bitsavers but haven?t
found anything so far.
Cheers!
--
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest private home computer collection?
t: @binarydinosaurs f: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk
2 Dec
2 Dec
3:32 p.m.
On Sun, 2 Dec 2018, Adrian Graham via cctalk wrote:
In my long ongoing quest to image and otherwise copy
the hard sectored
floppies with my Exidy Sorcerer I?m trying to find other floppy drives
I can use with it since I don?t like relying on just one set of
drives. I have a Cumana dual drive set that came with my TRS80 Model1
that I thought might be jumperable to 300rpm, indeed I can see drive
activity if I try and boot.
If those were being used on a TRS80 Model1, then they are already 300RPM.
Does anyone know where I might find the/a manual for
the drives?
They?re marked as Intertec 5002040 so I?ve been all over Superbrain
docs and PDFs on bitsavers but haven?t found anything so far.
If they were used on a Superbrain, then they are already 300RPM.
But, Be VERY careful with Superbrain documentation and [mis]"information".
They started off with an ordinary 200K 40 track MFM SSDD / Single Sided
Double Density 48tpi. (Like the PC-DOS 160K/180K)
When they went to 400K 40 cylinder MFM DSDD / double sided, double
density, still 48 tpi (like the PC-DOS 360K), they chose to call that
"QD" / "QUAD DENSITY"!! ?!?? (equating "density" with
capacity)
WHOA! Everybody else called THAT DSDD "Double Sided Double Density", and
used "QD" / "Quad Density" to refer to 80 cylinder Double density
96tpi!
So, when you see mention of Superbrain "QUAD DENSITY", they are referring
to a drive like the PC 360K! NOT what anybody else called "QUAD
DENSITY"
Mentions of "80 track" don't help, because that could be referring to 80
tracks made up of 40 tracks per side (40 sylinders), OR be referring to 80
tracks per side.
When Superbrain went to 800K 96tpi Double Density (which everybody else
was calling "Quad Density", Superbrain called THAT "SUPER Density",
which
they abbreviated "SD".
YES, they really did call their 800K format "SD"!
Q [Rhetorical]: What did "SD" mean to anybody else?
Superbrain's disk format was 10 sectors per track (numbered 1h through
0Ah), with 512 bytes per sector. The Address marks are pretty "normal",
althought 10 sectors per track can sometimes pose difficulties on NEC
controllers, but the data field in each sector is inverted. And, if I
recall correctly, they used an INCORRECT value in the "Head Number" field
on the sectors on the second side, but would accept disks with correct
headers.
I have heard that they used a Z80 for floppy control, but the disks are
consistent with a Western Digital 179x controller.
I doubt that they manufactured their own disk drives, but it is possible.
Look carefully at the drives for any hints of who actually made them.
Are these "full height" (SA400) or "half height"?
I had not heard of Cumana. Google says that it was a British company
(Guildford) peddling disk drives in their own cases, mostly for BBC and
Acorn.
Various forum posts describe Shugart 465 (96tpi), and Mitsubishi 4853
(96tpi) One on eBay looks like a Mitsubishi.
--
Grumpy Ol' Fred cisin at xenosoft.com
4:02 p.m.
Hi Fred,
On 2 Dec 2018, at 23:32, Fred Cisin via cctalk
<cctalk at classiccmp.org> wrote:
On Sun, 2 Dec 2018, Adrian Graham via cctalk wrote:
I should?ve known that.
In my long ongoing quest to image and otherwise
copy the hard sectored floppies with my Exidy Sorcerer I?m trying to find other floppy
drives I can use with it since I don?t like relying on just one set of drives. I have a
Cumana dual drive set that came with my TRS80 Model1 that I thought might be jumperable to
300rpm, indeed I can see drive activity if I try and boot.
If those were being used on a TRS80 Model1, then they are already 300RPM. When they went to 400K 40 cylinder MFM DSDD / double
sided, double density, still 48 tpi (like the PC-DOS 360K), they chose to call that
"QD" / "QUAD DENSITY"!! ?!?? (equating "density" with
capacity)
WHOA! Everybody else called THAT DSDD "Double Sided Double Density", and used
"QD" / "Quad Density" to refer to 80 cylinder Double density 96tpi!
So I?ve been reading :) I?m sure they weren?t doing it deliberately, hahaha.
field on the sectors on the second side, but would
accept disks with correct headers.
I have heard that they used a Z80 for floppy control, but the disks are consistent with a
Western Digital 179x controller.
They were always touted as twin-Z80 machines. I?ve always wanted one because when all I
had at school was a Research Machines 380Z (another twin drive CP/M machine) the
Superbrain LOOKED like a computer even though as I?ve been reading tonight it was
originally designed as a terminal.
I doubt that they manufactured their own disk drives,
but it is possible. Look carefully at the drives for any hints of who actually made them.
Are these "full height" (SA400) or "half height??
You?re right. Normally with Cumana stuff I do look for a manufacturer because yes, they
were known to me as makers of repackaged drives for the Acorn BBC Micro. In this case the
Intertec label is a bit of a red herring and the drives are actually Tandon TM100-1 full
height units. I?ve got the manual from a Rat Shack related site.
Thanks for making me look again :)
--
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest private home computer collection?
t: @binarydinosaurs f: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk
4:22 p.m.
> When they went to 400K 40 cylinder MFM DSDD /
double sided, double
> density, still 48 tpi (like the PC-DOS 360K), they chose to call that
> "QD" / "QUAD DENSITY"!! ?!?? (equating "density" with
capacity) WHOA!
> Everybody else called THAT DSDD "Double Sided Double Density", and used
> "QD" / "Quad Density" to refer to 80 cylinder Double density
96tpi!
On Mon, 3 Dec 2018, Adrian Graham via cctalk wrote:
So I???ve been reading :) I???m sure they weren???t
doing it deliberately, hahaha.
It's hard to say. At NCC, at the Intertec booth, they could not
understand WHY anybody would want to transfer files between disk formats,
other than to PIRATE their "proprietary software"! They even threatened
to sue me if I included it in XenoCopy!
So, they were not heavy into interoperability with other brands.
That was the first time that I added a format to XenoCopy while in a hotel
room. (Televideo was the second!). NCC was great. In addition to
those two formats, in exchange for buying him lunch, John Draper told
me everything that I needed to know to add UCSD P-System formats - (I did
NOT exercise with him.)
Intertec did not keep their promise - I could have used the free ink.
You???re right. Normally with Cumana stuff I do look
for a manufacturer
because yes, they were known to me as makers of repackaged drives for
the Acorn BBC Micro. In this case the Intertec label is a bit of a red
herring and the drives are actually Tandon TM100-1 full height units.
I???ve got the manual from a Rat Shack related site.
Thanks for making me look again :)
One more caveat! Radio Shack repurposed pin 32 (SIDE SELECT) to use as
their fourth drive select, and did their drive select with their cable,
rather than the jumpers. So did IBM, although they jumpered both drives
as second drive, rather than ALL jumpered as RS had done. IBM also used
them, as well as the TM100-2 (DS), so there are a LOT of sources for the
manuals.
--
Grumpy Ol' Fred cisin at xenosoft.com
4:38 p.m.
On 3 Dec 2018, at 00:22, Fred Cisin via cctalk
<cctalk at classiccmp.org> wrote:
Was any manufacturer? I does seem to me that everyone deliberately made their CP/M format
different despite using the same or similar chipsets. I was surprised to read in the docs
for my Osborne Executive that it COULD read a couple of other formats.
> When they went to 400K 40 cylinder MFM DSDD /
double sided, double density, still 48 tpi (like the PC-DOS 360K), they chose to call that
"QD" / "QUAD DENSITY"!! ?!?? (equating "density" with
capacity) WHOA! Everybody else called THAT DSDD "Double Sided Double Density",
and used "QD" / "Quad Density" to refer to 80 cylinder Double density
96tpi!
On Mon, 3 Dec 2018, Adrian Graham via cctalk wrote:
So I?ve been reading :) I?m sure they weren?t
doing it deliberately, hahaha.
It's hard to say. At NCC, at the Intertec booth, they could not understand WHY
anybody would want to transfer files between disk formats, other than to PIRATE their
"proprietary software"! They even threatened to sue me if I included it in
XenoCopy!
So, they were not heavy into interoperability with other brands. That was the first time that I added a format to
XenoCopy while in a hotel room. (Televideo was the second!). NCC was great. In addition
to those two formats, in exchange for buying him lunch, John Draper told me everything
that I needed to know to add UCSD P-System formats - (I did NOT exercise with him.)
Intertec did not keep their promise - I could have used the free ink.
What machine were you using for hotel room coding?
One more caveat! Radio Shack repurposed pin 32 (SIDE
SELECT) to use as their fourth drive select, and did their drive select with their cable,
rather than the jumpers. So did IBM, although they jumpered both drives as second drive,
rather than ALL jumpered as RS had done. IBM also used them, as well as the TM100-2 (DS),
so there are a LOT of sources for the manuals.
This pair are jumpered as I?d expect, DS0 and 1 with a terminator block. The manual says
they?ll work with multi-hole floppies so I?ll strip them down later and give them a good
clean.
--
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest private home computer collection?
t: @binarydinosaurs f: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk
5:15 p.m.
New subject: Reminiscing (Was: ISO Intertec 5.25" floppy drive jumper settings
> So, they were not heavy into interoperability with
other brands.
On Mon, 3 Dec 2018, Adrian Graham via cctalk wrote:
Was any manufacturer? I does seem to me that everyone
deliberately made
their CP/M format different despite using the same or similar chipsets.
I was surprised to read in the docs for my Osborne Executive that it
COULD read a couple of other formats.
I HAVE TO respond to THAT! No way can I let THAT slide!
I once cold-called Gary Kildall to ask him to consider standardizing 5.25"
disk format. His response was, "THE standard is 8 inch single sided
single density". I said, "but what about 5.25 inch?" He repeated,
"THE
standard is 8 inch single sided single density."
During the famous "shooting self in the foot WITH AUTOMATIC WEAPONS"
session, Adam promised that their next machine could read and write every
disk format in existence! About a week later, they contacted my publisher
to discuss licensing XenoCopy!
I used to run into Adam occasionally. And then, after his computer
company folded, he briefly peddled an external HDD in a odd shaped case
(at computer swaps!)
When Lotus sued Paperback software, I suggested buying one of the pieces
of the defunct Visicorp (CHEAP at the time) as an impenetrable defense
(cf. Novell's purchase of DRI). But, it was just barely too late.
I miss him.
I was PLEASED to see the prevalence (bundling?) of Uniform from
MicroSolutions with Kaypro, even though they were my biggest competitor.
Howard Fullmer (Morrow Designs) was working on a multi-format system that
was attempting automatic format recognition. I don't think that he
finished it. I heard that he died (I miss him), but I can't find
confirmation, and George Morrow is obviously unavailable. Anybody KNOW?
(One of my TRS80s had his "Parasitic Engineering" 8" CP/M modifications
(sandwich boards below Z80 and 1771))
What machine were you using for hotel room coding?
At that time, a Compaq. And, I used a Compaq in a gazebo in a park in the
rain in Hilo when I added WRITE capability.
But, I soon switched to a generic lunchbox.
And, for a while Joe Garner (Elcompco) loaned me an XT system in a
Halliburton attache case (5" display). His CP/M system had already been
available for sale in my Computer Faire booth (right accross the
aisle!) when Adam made his spectacular launch of "THE FIRST portable
computer")
It just ain't the same no more.
If John Titor is listening, my offer stands for a one way ride back to mid
sixties.
--
Grumpy Ol' Fred cisin at xenosoft.com
4:32 p.m.
When they went
to 400K 40 cylinder MFM DSDD / double sided, double
density, still 48 tpi (like the PC-DOS 360K), they chose to call that
"QD" / "QUAD DENSITY"!! ?!?? (equating "density" with
capacity) WHOA!
Everybody else called THAT DSDD "Double Sided Double Density", and used
"QD" / "Quad Density" to refer to 80 cylinder Double density 96tpi!
So I?ve been reading :) I?m sure they weren?t doing it
deliberately, hahaha.
2211
days inactive
2212
days old
6 comments
2 participants
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binarydinosaurs＠gmail.com -
cisin＠xenosoft.com