2 Dec
2018
2 Dec
'18
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