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View Full Version : Got my MDS-225 today!



falter
December 10th, 2013, 09:30 PM
It arrived! And it works (I think)!

Weighs a ton, but I got it up on the bench. Fired it up -- initial disappointment because nothing appeared on the screen. Then I opened it up and found the display and drive (I think) connectors were disconnected. Bracing myself for whatever reason they might have been that way, I turned it back on again and voila! I have a cursor, and can type. No boot disk though, and no idea how I'd get it to boot anything even if I did. All I can do is type, move the cursor around on the screen.. that's it.

Overall it's in well worn but not too bad shape. When I popped off the front panel cover though I was dismayed to see the ram board is all bent and flexed. I have no idea if it's still working or not, and I can't seem to pull it out to try to straighten it. I'm afraid I"ll break it (or rip my fingers to shreds.. it's sharp).

Now I just have to find an OS disk and some instructions on how to boot this thing. I think it's proper name is Intel Intellec Series III MDS-225.

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falter
December 10th, 2013, 09:31 PM
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This is the card that's kinda bent. If anyone has any tips on how I might get it out of there without destroying it.. I'm all ears. :)

Chuck(G)
December 10th, 2013, 09:48 PM
It looks as if the RAM card was bounced out of its card guides during shipping. Not fatal. Gently push it up until it pops into the guides and the you should be able to pop it out using the release levers at the top.

What I don't see in your box is the 2-card floppy controller. That's not going to be easy to find.

falter
December 10th, 2013, 10:03 PM
It looks as if the RAM card was bounced out of its card guides during shipping. Not fatal. Gently push it up until it pops into the guides and the you should be able to pop it out using the release levers at the top.

What I don't see in your box is the 2-card floppy controller. That's not going to be easy to find.

I found a manual online for this machine.. according to it.. I have all the cards I'm supposed to have? It does show a two card floppy controller, but says (optional) underneath it.

Al Kossow
December 11th, 2013, 08:14 AM
Now I just have to find an OS disk and some instructions on how to boot this thing.

try
http://bitsavers.org/pdf/intel/MDS3/
and
http://bitsavers.org/bits/Intel/MDS/

Chuck(G)
December 11th, 2013, 10:41 AM
Ah, that's right--the 200 series used the 2-board FDC for double-density drives. Otherwise, you were limited to 250K single-density/single-sided disks. Still, there's a SSSD image there on bitsavers as Al points out.

The MDS-800 used a 2-board single-density controller also (no integrated controller). It used Intel 3000-series bit-slice logic and ran hot as a two-buck pistol.

falter
December 11th, 2013, 12:19 PM
Thanks guys. Now I guess the trick is how to get it from PC to an 8 inch floppy the Intellec can read. I'm guessing I'd have to find an old ISA 8 inch floppy controller card for my old 486 or something? Download the image to it via the internet and then write it with that?

Then there's the matter of finding an external drive that it'd connect to.

I'm assuming nobody's bothered to invent something for the MDS that works like ADTPro does for Apple..

Chuck(G)
December 11th, 2013, 01:28 PM
You can probably use the floppy unit that came with your MDS. The biggest hurdles would be making up a cable to go from the box to a PC. Oddly enough, more recent (e.g. P2-P3+) machines have better odds of being able to write a single-density 8" floppy than a 486-era machine. (The XT-FDC can certainly do that, however, as that was built in).

If you've got more than a couple of machines that will run DOS, give the TESTDISK utility from Dave Dunfeld a shot to winnow out the candidates.

falter
December 11th, 2013, 03:37 PM
Yeah I don't know if I'm skilled enough to tackle a cable job. I kind of need something plug'n'prayish. Maybe I should just find out who posted the images and ask how they made them.

I followed the manual's instructions for trying to put the MDS into a mode where it'd try to boot (obviously I don't have the disks, but all the same I expected it should be able to attempt it). Supposedly you simply turn the machine on and when the prompt comes up, you hit Reset. However hitting reset in my case produces nothing... I can type endlessly but the machine makes no response. More reading I guess.

A problem has cropped up with the screen.. sometimes when it starts, it's like it's retracing:

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NeXT
December 11th, 2013, 04:15 PM
The monitor probably needs a good recap. Looks like it's overdrawing.

falter
December 11th, 2013, 04:35 PM
The monitor probably needs a good recap. Looks like it's overdrawing.

I made an adjustment to what I think was the horizontal position dial inside.. and now it seems to be ok.

Oh and I found a switch at the back -- has three positions: LOCAL, LINE and DIAGNOSTIC. It was on LOCAL. When I switched to LINE, suddenly I had a boot prompt.

Chuck(G)
December 11th, 2013, 05:50 PM
Yeah I don't know if I'm skilled enough to tackle a cable job. I kind of need something plug'n'prayish. Maybe I should just find out who posted the images and ask how they made them.

If you're willing to open the floppy box, you can cable up a solution using John Wilson's fdadap (http://dbit.com/fdadap.html).

falter
December 11th, 2013, 06:30 PM
If you're willing to open the floppy box, you can cable up a solution using Johttp://dbit.com/fdadap.html]fdadap[/url].

Yes I was looking at that.. so I'd just plug in the end of the drive cable currently going to the mds motherboard Into that instead, and then I'd just need to find a straight thru floppy ribbon cable to go from the adapter to the pc's floppy controller. I'm assuming since he says a straight cable.. that a regular floppy cable wouldn't work since some of the wires twist at the end. I wonder I could negate the need for a power adapter by just powering up the mds with the drive still connected for that.

Chuck(G)
December 11th, 2013, 08:22 PM
The twist at the "drive A:" end of a floppy cable doesn't matter. Just use the "B:" connector of a 2-drive cable. Unless my memory fails me, the MDS drive box (the 2DS did, at any rate) has its own power supply. Good thing too, as the 8" drives (usually Shugart SA-801s) require a pretty hefty +24V (and +5/-5) supply, in addition to 120VAC for the spindle motors. No need to use the MDS box itself for that.

Chuck(G)
December 12th, 2013, 05:58 PM
Tell ya what--if you're really interested in getting this thing going, I'm willing to send either an ISIS-II boot floppy or a CP/M boot floppy (single density) if you'll pay my shipping, assuming you're in the USA. That will save you some shenanigans in getting a boot floppy.

Note to others--if you've got an MDS with the double-density controller, the thing uses MMFM, not MFM, so you can't write floppies with a standard PC floppy controller--you need to use single-density floppies, which all MDS controllers can read.

Ragnarock
February 27th, 2018, 12:12 PM
Falter, did you get your MDS working?

falter
February 27th, 2018, 09:23 PM
It runs... I just don't have an ISIS boot disk.

Chuck(G)
February 27th, 2018, 09:46 PM
I believe there's on on bitsavers. You should be able to boot the FM (single density one).