bier@cottage.cs.wisc.edu (George Bier) (05/16/89)
I have a friend with a Leading Edge Model M (M is for the Mitsubishi model,
identical to a model sold under the Sperry label). He is interested in
upgrading the machine with a hard drive and asked me which ones would work
with his machine. Sadly, I haven't the faintest idea if he can even add
a hard drive, but I was hoping that someone out there would know.
It seems like I might have read somewhere that the Bios on the model M would
not support a hard drive, or maybe it is that the msdos version (I think it
is 2.1) doesn't or something like that. If anyone knows what the facts are
on this, would they please write me? If this vague memory is incorrect and
someone knows for certain of a hard drive controller that works with the
Model M, I would appreciate that information instead.
thanks,
--george
Internet: bier@cs.wisc.edu
UUCP: ...!{harvard,seismo,topaz,akgua,allegra,usbvax}!uwvax!bier
"Nobody leaves this place without singing the blues"nfs0294@dsacg1.UUCP (Glendell R. Midkiff) (05/16/89)
From article <7522@spool.cs.wisc.edu>, by bier@cottage.cs.wisc.edu (George Bier): > someone knows for certain of a hard drive controller that works with the > Model M, I would appreciate that information instead. I had a Leading Edge Model M a few years ago. It used DOS 2.1 and had a 10 meg hard drive (Miniscribe, I believe). I don't recall anything peculiar about installing a hard drive in it. -- |-----------------------------------------------------------------------| |Glen Midkiff osu-cis!dsacg1!gmidkiff | | Phone: (614)-238-9643 @DLA, Systems Automation Center, Columbus, Oh. | |-----------------------------------------------------------------------|
forrest@phobos.sybase.com (Jon Forrest) (05/17/89)
I have a Leading Edge Model M with a Tandon 20 Meg disk and
a DTC controller and it works just fine. I've had it for 4 years.
Jon Forrest
forrest@sybase.com
{pacbell,sun,{uunet,ucbvax}!mtxinu}!sybase!forrest
415-596-3422bumy@vax5.CIT.CORNELL.EDU (05/18/89)
This is my first attempt at posting so in case the subject line isn't
correct, the topic is the Leading Edge model M.
I missed the original post but caught the reply in item 30128. I'm
putting down some of what I've learned about the macine in the last 2 years.
The operating system can be upgraded to IBM-DOS 3.1 but no higher. This
can be done on most of the Model M machines but some have an earlier BIOS which
is not compatible; an upgraded chip was available last year but I didn't need
it. (phone #'s at end) The only way to know for sure is to install it. If it
hangs for no apparent reason in mid operation, the BIOS is probably at fault.
My machine has been running on IBM-DOS 3.1 for about 10 months with no
problems. The BIOS chip reads (Mitsubishi C 1984 WESY30 | k16 | A). Other
brand BIOS chips will get you some functions but the screen is really wierd
(don't ask how I know), basically the hardware doesn't match. If you change
DOS you will need a clock as the original won't function. Also, the hard disk
will have to be reformatted. The jump from Leading Edge DOS to IBM-DOS is too
much and the directories won't read. The upgrade in DOS allowed me to use some
new programs which functioned better with 3X, in fact 1 program requires DOS 3
or higher. I don't know about MS-DOS compatibility and, as I understand it,
the problem with 3.2 and up is that the floppy will no longer format correctly.
I replaced the 8088 with a V-20 and boosted the performance considerably.
The Norton Index is 2.9, the graphics really zip, and I found that the hard
drive loaded in about half the time (30 S for a file that had taken 55). BUT,
I don't recommend the procedure because the CPU is soldered on the
motherboard. I unsoldered it and installed a socket with the V-20. It is not
a trivial task, but I'm a hardware hacker and I like to play with hot soldering
irons.
The original hard drive is a Miniscribe model 3425 (note to make this a
drive 2, set switches 2,3,4,7 on). It's sitting on the bench beside me
because I pulled it last night and installed a Seagate 238-R and a WD 1004A-27X
controller. 20 Meg was just too small for our current needs. The controller
is an Adaptec full length card. I don't see any specific indication of model
but there are a lot of numbers on it and a 1984 copyright notice. There was no
problem installing 30M drive and one other lab here has done the same running
Leading Edge Dos.
Be aware that if there are interrupt conflicts, the processor downshifts
to low speed and stays there. There is no indication of changeover except the
screen glitches. I found this one when I installed a mouse and the machine ran
OK until the first time I pressed the button, then it became sluggish.
Phone numbers I used last year for inquiries
Leading Edge Customer support 617-821-4300
The parent company is Mitsubishi and they also helped with some other info
213-515-3993.
I don't know the current status of any of the phone lines or who
owns what company or division. The machine itself is a Sperry design and it
was suggested that I might be able to upgrade with their DOS. I have no
further info on that possibility.
Additional note
I've been working with DECNET-DOS ethernet link to a VAX for the past 8
months and have some observations about its problems. And, it does have some
really neat functions and works well for us. If there is any interest I can
post what I've learned, however, I'm not sure this is the right group.
*****************************************************************************
*
SOMETIMES IT IS NECESSARY TO GRAB THE * Jerry M. Wright
BULL BY THE TAIL AND FACE THE SITUATION.* Department of Pharmacology
* NYSCVM
***************************************** Cornell University
BUMY@VAX5.CIT.CORNELL.EDU * Ithaca, NY 14853
*****************************************************************************weston@ucselx.uucp (weston t) (05/19/89)
I added a ST-225 hard disk to my model M. this disk is slow (65 ms.), but otherwise quite satisfactory. I forget the name of the controller-- I'll check it out if anyone asks me. I also upgraded to DOS 3.1, because some software (like Microsoft Codeview didn't work on 2.11, and Microsoft was ABSOLUTELY no help on the phone). There is supposed to be a version of DOS 3.x available from Sperry (who still sell the leading edge with their label on it) but I understand they are not willing to part with it. I used a OEM-modified 3.1 from Falcon technologies, but it would not set the leading edge clock properly. I found the right bios call to do this, and wrote a TP5.0 routine to call it. works fine, will send it if asked. I also had some peculiar behavior on hard disk errors and soft boots, so I (1) found the dying sector (only one in 4 years) and marked it, and (2) bought some new bios chips ($20) from by local dealer. no further problems although it buzzes briefly on soft boots. Tom Weston ucsd.edu!sdsu!ucselx!weston Disclaimer: SDSU could care less what I think.