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Intellec MDS-800 and related Multibus stuff

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sysadmindave

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I've just acquired a significant stash of early microcomputer equipment and honestly I'm a bit overwhelmed figuring out where to start evaluating it.

These computers and related materials were used to develop and support the Bösendorfer SE reproducing piano system (the controller was a Z80-based Multibus embedded computer connected to a PC for file storage). These pianos were commercially sold for a short time in the late 1980s, but few were built & sold due to very high pricing- they mostly went to universities and a few wealthy individuals. These are amazing instruments, BTW, and can EXACTLY record and play back the smallest nuances of a top piano performance on the instrument- you'd swear the artist was in the room performing when you hear one of these pianos play- they are unsurpassed in reproduction quality even now, 40+ years after they were built, and most of them are still operational.

The inventor and engineer that developed the piano reproducing system and licensed it to Bösendorfer (Wayne Stankhe) purchased this equipment new starting in late 1975, specifically to develop the computerized reproducing piano. He's now elderly and downsizing possessions. He wanted to get rid of these items but couldn't bear to trash them. I expressed an interest in having them when he brought it up to me, so they are now in my garage.

The equipment includes:
  • Intel Intellec MDS-800 computer system with 64K RAM expansion and disk controllers (haven't looked at them specifically yet, but I know they are not the Intel ones)
  • Winchester Systems 5Mb hard disk cabinet for the above- I think it was Winchester Systems first commercial product
  • 2 dual-floppy cabinets with 8" floppy drives installed (4 drives total), not Intel branded
  • 1 single floppy cabinet with 8" floppy drive installed, not Intel branded
  • Monolithic Systems Multibus development system- enclosed card cage and cabinet with power supply and dual 8" floppy drives. This thing is HEAVY. (if you're counting, that's also 7 8" floppy drives in total)
  • Custom Multibus open cage (about 6 or 7 slots?) with power supply mounted on an aluminum plate. Includes several cards installed including a processor card and floppy driver
  • A number of loose Multibus cards- misc peripherals, including a number of floppy controllers and various other processor cards, some with Z80 and Z280 chips, at least a couple of custom cards for the pianos
  • Perhaps about 50-100 8" floppies with various development tools, OS, and data
  • What looks like full original documentation for all of the above
Just finished picking all of this up yesterday- 2 full car loads! I need to start by doing an inventory and some research on the various cards I think.

I've also ordered a Greaseweazle and compatible cabling for the single 8" floppy cabinet to archive the contents of any of the floppies I can recover.

Any suggestions as to what I should concentrate on first?
 
That will keep you off the streets for a while!

I used one of those Intellec systems when I was on various 8086 and 80286 training courses at Intel.

We ended up purchasing the a later system (that we still have in a store room). Never used for years...

Have you found the online MULTIBUS documentation website?

Dave
 
First computer I actually had hands-on with was a dictation management system made by Dictaphone. It used the Intel SBC 80/20, some peripheral cards, 2 Shugart SA-400 drives, and a couple of Lear Seigler ADM-3A terminals. I'd love to build a multibus system if I could find something that was built around the Z-80. I've be daring myself for years to design one, but never have.
 
antiquekid3 said:
Very cool. Is the LX system still being produced?
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Part of the agreement when Wayne sold the LX system design to Steinway was that he would no longer make or sell them himself. A few LX kits may still be available somewhere, but I don’t know of any personally. The LX system was sold as the original Spirio design, but the newer models that record (R models) were a redesign by a third party company contracted by Steinway.
 
daver2 said:
That will keep you off the streets for a while!

I used one of those Intellec systems when I was on various 8086 and 80286 training courses at Intel.

We ended up purchasing the a later system (that we still have in a store room). Never used for years...

Have you found the online MULTIBUS documentation website?

Dave
Click to expand...
I’ve found a fair amount on bitsavers.org- is that the archive?
 
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MykeLawson said:
First computer I actually had hands-on with was a dictation management system made by Dictaphone. It used the Intel SBC 80/20, some peripheral cards, 2 Shugart SA-400 drives, and a couple of Lear Seigler ADM-3A terminals. I'd love to build a multibus system if I could find something that was built around the Z-80. I've be daring myself for years to design one, but never have.
Click to expand...
if I find I have one or more spares I don’t want, I’ll be sure to let you know. I am certain there are a number of processor cards, at least some with Z80s.
 
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Ah, gotcha. I have been trying (albeit not very hard) to find a nice Ampico for a while, but the videos of the LX system always looked interesting.
 
antiquekid3 said:
Ah, gotcha. I have been trying (albeit not very hard) to find a nice Ampico for a while, but the videos of the LX system always looked interesting.
Click to expand...

Might be getting a bit off-topic, but I agree that the LX system is excellent and interesting. It was based on much of the design and technology of the earlier SE pianos, but with compromises made to reach an attainable price for a broader market and allow for easier installation for the piano aftermarket. The SE system had to be factory installed due to its complexity and the components were quite costly.

As hinted to above in my other posts, the SE reproducing system is a bit of a retro-computing project on its own- a few of the earliest units were delivered running CP/M on a standalone Multibus computer system with 8" floppy disk drives for storage. Only a little later, they were changed so that the Multibus controller was running dedicated host software on bare metal (no OS), and the pianos were then sold with original IBM PCs running MS-DOS as UI and file storage systems. I think that most or all of the early instruments were retrofitted with the newer computer systems.

The SE system also contains a sophisticated optical sensor system on the hammer shanks and under the keys for precise recording that the LX lacked. SEs use those sensors in addition to coils placed strategically on the solenoids to sense the solenoid and action positions accurately, using that data to control the solenoids in a closed-loop. With that arrangement, they could reproduce the entire dynamic range of the piano very accurately, from the softest notes (or even ones that didn't actually sound, but lifted the dampers) to the loudest fortissimo of which a concert pianist is capable (VERY loud). Truly an impressive engineering feat, particularly for the time.

I have worked on (repairs & modifications) a number of the few SE pianos since the mid-1990s- fell into that quite by accident when I was a young engineer, but it's been a fun occasional side gig.

Early last year I was able to acquire one of these instruments (a 225SE) in which the SE system had failed and the previous owner (a university) had given up on fixing, but they had kept the acoustic instrument very well maintained. Fortunately for me, I was able to get it for a very reasonable cost and fix it without too much difficulty.

I've spent quite a bit of time in the last year porting the old MS-DOS software programs supplied with these instruments to Linux so they can be more conveniently used with today's computer technology. Wayne has graciously given me his blessing and support in this effort.

Wayne also reengineered the Multibus controller recently into a single-board FPGA-based system similar to the LX (based on its controller design), so I now have one of those as my primary piano controller in addition to the original Multibus version that came with it. In the end analysis with these systems, it's ALL about the music, and it's wonderful to hear it play concert-level performances in my living room!

My piano was one of the later units, and originally was delivered with an IBM PC-XT/286 (model 5162), which I also received with the piano in like-new condition- that's also been an interesting retro-computing exercise.
 
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Re: recovering files from Intel MDS-800

The Intel disks are single-sided (lower side when label is on top). The issue is that the encoding is M2FM, which is not supported by standard floppy controllers. Getting at the files involves specialised software - which does exist.

The Greaseweazle will do a fine job of capturing flux images - providing you choose the 'raw' output format. You may need to inspect source code to work out the command line.

I recommend joining the intel-devsys Google group to obtain further advice about recovering files. There is also a group on Facebook.
 
>>> I’ve found a fair amount on bitsavers.org- is that the archive?

There was another website I was thinking of - but it has disappeared...

Dave
 
sysadmindave said:
if I find I have one or more spares I don’t want, I’ll be sure to let you know. I am certain there are a number of processor cards, at least some with Z80s.
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That would be fantastic. Heck, even knowing some particulars on a Z-80 based Multibus card would be a start so I could dig up some documentation. I wouldn't mind even spinning up a new board version if I had a schematic of one. Folks are always doing that with S-100 stuff, so why not Multibus too.
 
antiquekid3 said:
Very cool! Would you be willing to make a new post on your instrument with photos/videos?
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I'm happy to do this, but it may be a few days until I can get to it. Where should it be posted? This forum (I think it's appropriate given the age and hardware), or another? And, do you have any particular questions or topics you'd like to know about?
 
jonhales said:
Re: recovering files from Intel MDS-800

The Intel disks are single-sided (lower side when label is on top). The issue is that the encoding is M2FM, which is not supported by standard floppy controllers. Getting at the files involves specialised software - which does exist.

The Greaseweazle will do a fine job of capturing flux images - providing you choose the 'raw' output format. You may need to inspect source code to work out the command line.

I recommend joining the intel-devsys Google group to obtain further advice about recovering files. There is also a group on Facebook.
Click to expand...
This information is much appreciated! Not sure that the disk controllers I have are M2FM though- they might be something else since they are not Intel branded. Needs more research I think- when I inventory them I'll post the model numbers in this thread.
 
The first 2 cards, from the open Multibus cage in the background.

Wayne mentioned (and I had forgotten) that the floppy controllers included with this equipment were Zendex. I think the CPU card pictured is likely to be a GSI/Lumonics single-board Z80? Not exactly matching anything I could find online, but the layout is close to a Google image search for that brand- I don't recognize the logo. I also took snapshots of the solder sides in case anyone is interested, but I'll omit them for now.

IMG_4800.jpeg
IMG_4798.jpeg
 
And here are the cards currently in the MDS-800- no floppy controller currently, but Wayne said there were others in the boxes- I'll send photos of those when I go through the boxes. Of this set, the last card is the HD controller for the Winchester Systems HD cabinet. The brown card was a custom one Wayne designed for a tape interface- I don't know if it was ever released or sold. Apologies for the out of focus photos and mixed orientations.

IMG_4817.jpegIMG_4819.jpeg

IMG_4815.jpegIMG_4813.jpegIMG_4811.jpegIMG_4809.jpegIMG_4807.jpegIMG_4804.jpegIMG_4802.jpeg
 
sysadmindave said:
And here are the cards currently in the MDS-800- no floppy controller currently, but Wayne said there were others in the boxes- I'll send photos of those when I go through the boxes. Of this set, the last card is the HD controller for the Winchester Systems HD cabinet. The brown card was a custom one Wayne designed for a tape interface- I don't know if it was ever released or sold. Apologies for the out of focus photos and mixed orientations.

View attachment 1302600View attachment 1302601

View attachment 1302592View attachment 1302593View attachment 1302594View attachment 1302595View attachment 1302596View attachment 1302597View attachment 1302598
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sysadmindave said:
The first 2 cards, from the open Multibus cage in the background.

Wayne mentioned (and I had forgotten) that the floppy controllers included with this equipment were Zendex. I think the CPU card pictured is likely to be a GSI/Lumonics single-board Z80? Not exactly matching anything I could find online, but the layout is close to a Google image search for that brand- I don't recognize the logo. I also took snapshots of the solder sides in case anyone is interested, but I'll omit them for now.

View attachment 1302591
View attachment 1302590
Click to expand...
I would love to get any info on the Z-80 CPU Multibus board. That would be a great one to build a Multibus system around.
 
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