Rumor has it that Fred Cisin (XenoSoft) may have mentioned these words:
>On Tue, 9 Nov 1999, Roger Merchberger wrote:
>> P.S. To keep this on-topic, does anyone have instructions on the hack to
>> convert the above-mentioned floppy controller to be able to handle 3.5" HD
>> floppy drives? I'd *love* to have a 1.44Meg floppy formatted under OS/9...
>> :-) Also, is there any way (without reconstructing the 6 million dollar
>> man...) to get two floppy controllers online using the MultiPak?
>
>My recollection was that there were several different vartieties. Each
>one will have slightly different issues.
Hmmmm... Looks like I need to grab the controller catalog # (and other
specifics) and keep it in my Palm...
>To add 3.5" HD floppies, you will need to provide a different clock, way
>to change it back and forth, and support for one more signal to the drive.
I know you need a different clock (500Khz signaling rate vs. 250Khz for
double-density) but I'd like to know if it's as simple as a DPDT switch &
another crystal, or are there more things to keep a lookout on (like
different buffers, software changes WRT timing issues, stuff like that...).
>Why do you want to run more than one FDC? If it is to run 4 instead of 2
>drives, you can do that with minor hardware and software hacks to a
>controller.
Well, IIRC the most drives you can hang off of one controller is 4 SSDD
drives, or 3 DSDD drives because the Side Select signal was used for one of
the drive select pins. (Again, I think... If I'm wrong, please enlighten
me.) I was looking to hang 3 DSDD & 3 DSHD drives off my CoCo... purely for
shits & giggles. If it's a ton of hardware work, "nevermind" comes to mind.
However, if it's some hardware & hacking some device drivers, then... I've
always wanted to hack around with the device drivers of OS-9... :-)
Just musings of random tinkering... ;-)
Roger "Merch" Merchberger
--
Roger "Merch" Merchberger --- sysadmin, Iceberg Computers
Recycling is good, right??? Ok, so I'll recycle an old .sig.
If at first you don't succeed, nuclear warhead
disarmament should *not* be your first career choice.
>Can RT-11 deal in any way with an RA92?
Yep, it sure does. RT-11 will deal with drives up to 8 Gbytes by use of the
SET DUn:PART=nnn partitioning method. How you keep track of what's
in all 256 partitions is your business :-).
Even larger drives can be used with RT-11, but you only get to use the
first 8 Gbytes. I've got a RT-11 5.7 system here with a 9.1 Gig
Micropolis drive attached.
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
I have a couple images of a DigiLog TeleComputer at:
www.cs.umn.edu/~lemay/digilog
It doesnt have a manufacture date, but it was purchased by the university
on or before 1973. I have the three missing keycaps, but i suppose I
should see if i can find some replacement keys, since the posts are
broken off on 3 keys. They have a post vaguely like a phillips head
screwdriver.
-Lawrence LeMay
Ok, I have a pair of circuit boards, i'm not sure what these belong to:
floppy disk controller
85-2807-2
HEATH COPR
120882 1982
--------------------------
HUDSON AND ASSOC.
Z SUPPORT CARD
COPYRIGHT 1984
Any ideas? The edge connector is 50 conectors per side. roughly 10 inches
wide by 5.5 inches high.
-Lawrence LeMay
PS: i picked up a DigiLog Telecomputer. appears to be some sort of
portable terminal without monitor (1 BNC video conector). University
date code is from 1973. I'll put some pictures of this up later.
>> Yep, it sure does. RT-11 will deal with drives up to 8 Gbytes by use of the
>> SET DUn:PART=nnn partitioning method. How you keep track of what's
>> in all 256 partitions is your business :-).
>And How you keep track of what's in all 256 partitions ?
Admittedly, keeping track of all those partitions can be dizzying
sometimes.
There are some handy "tricks" (I put that in quotes since many of
us RT-11 oldtimers have been doing these for years, and these are all
documented tools, but sometimes used for other purposes than to aid my
failing memory) for keeping volumes straight:
1. Use the /VOL qualifier when INITting the volume to put something
descriptive there. For example:
RT-11FB V05.07
.create junk.dsk[100]
.mou ld4 junk.dsk
.init ld4:/vol
LD4:/Initialize; Are you sure? Y
Volume ID? Descriptive
Owner? Information
2. If you've done (1) above, then you can use the /VOL qualifier on DIR
to remind yourself what's on that partition:
.dir/vol ld4:
09-Nov-1999
Volume ID: Descriptive
Owner : Information
0 Files, 0 Blocks
92 Free blocks
3. Use logical names to identify the volumes, and a command procedure
to define them all. (There is no real equivalent to a logical name in
many modern OS's, including Unix, unfortunately. A logical is kinda/sorta
like a Unix mount point, but a logical is far better because you can
redefine as you find handy.) With RT-11 you only get
3-character logical names, but that's a start:
.ASS INF LD4
.ASS SRC DU3
.ASS BIN DU1
etc.
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
Can RT-11 deal in any way with an RA92?
I'm going to find out later tonight or tomorrow, but if anyone knows ahead
of time that it works/doesn't work that would be better. ^_^
-------
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jperry(a)eeglossary.com
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