Tektronix 8501 Data Management Unit

I had one of these a long time ago...it was called an 8560 Microprocessor Development System. The machine I had was in a similar case to the 8501, but inside was a LSI 11 CPU board (original DEC, as I remember), and non Q-Bus backplane that Tek devised that could accept Tek-made memory and peripheral boards. The machine that I had had a Micropolis 8" harddisk (can't remember the model), and a Qume DT-8 8" floppy drive. The Micropolis drive sounded like a jet airplane when it spun up, along with the really noisy fans in the cabinet itself. It was almost uncomfortably loud. I think the hard disk held a total of 35 Megabytes. The machine did run Tektronix-munged version of V7 Unix called TNIX. The intent of the machine was as a code development and emulation system for microprocessor system and software development. Tek added a whole number of different assemblers for many microprocessors...I remember there were cross assemblers for 8080, 8085, Z-80, 8086, 6800, 6809, 68000, 6502, and others. I actually used some of the assemblers to build bits for various microprocessor projects that I tinkered with at the time (mostly 6809). The 8650 had two (as I remember) RS232 serial ports on it. You could hook up terminals to both ports and have multiple sessions running. There was an emulator subsystem that could be connected into the system to allow emulation under control of the TNIX environment. As I remember, the emulator was another unit about the size of the 8650 that connected in through a special interface, that provided an in-circuit emulation capability for a number of different processors. These development systems were used quite heavily within Tektronix for development of a number of products, including Tek's first foray into digital oscilloscopes, the Tektronix 11000-series machines. I wish I still had that old beast...I ended up giving it away to someone who seemed to want it more than I did at the time...I was getting ready to move, and gave it away rather than moving it. It was a fun machine to tinker with. I remember once that I tried putting the source to 'rogue' on it and trying to compile it...never got it to compile properly. I think the compiler was not the standard 'cc' compiler as I recall, and it had some internal statically allocated tables that would overflow when trying to compile 'big' stuff. The machine wasn't really intended for Unix development work, so I don't think much effort was made to make the Unix environment anything more than an interface for the emulation and cross-assembler capabilities of the system. Another memory: When Tek scrapped the MDP group (the Microprocessor Development Products) that made the 8650 and other development products) a bunch of those old Micropolis 8" drives showed up at the Tek country store. I got a few of 'em. Interesting drives. I managed to go through the Tektronix engineering stock microfiche file and find data on the interface to the Micropolis controller that piggybacked on top of the drive electronics. A simple parallel interface, similar to SCSI, but quite a time before SCSI existed. At the time, Tek these wonderful little systems called "Board Buckets". Board Bucket systems were designed internally by a group that was part of MDP. They were a small aluminum chassis with a backplane (designed by Tek), an external power supply box, and a whole slew of different boards that could be plugged in. I recall that the original board bucket systems were used as part of the development of the Tek 4051 computer. There were CPU boards for the Motorola 6800, 6809, and I believe 8085, Z-80, and perhaps even 68000. There were static and dynamic RAM boards, PROM boards, an EPROM programmer board, a 300-baud modem board, a video interface (using, I think, the TI chip used for the video section in the TI 99/4), a floppy disk controller, an 8-port serial board, and more. Anyway, I had a number of board bucket systems that I built up from parts as machines to play with. Anyway, I ended up building an interface for the old Micropolis drive that would plug into the Board Bucket, and ended up writing a device driver for OS-9 that would allow it to talk to the Micropolis drive! I had a 6809-based board bucket that had two 5 1/4" single sided, double-density floppy drives, this 35 Megabyte Micropolis hard disk, an 8-port I/O board, 64K of RAM, and a 1 Megabyte RAM disk that I also hacked together. It was a very amazing system for the time. I still have a lot of the board bucket stuff...but alas, I think that I threw away the hard disk drives as part of cleaning up before yet another move, and all of the OS-9 stuff is long since lost. OS-9 was a really cool OS from my recollection..I had a great deal of fun tinkering with it...that is, until I ended up building a Tektronix 6130...Tek's National 32016-based Unix (UTek) system of the only *real* Unix (4.2 BSD). The machine had a whopping Megabyte of RAM, two serial ports, and a Micropolis 1302 20MB ST-506 drive, and a 5 1/4" half-height floppy drive. As soon as my 6130 was up and running, my interest in all the old OS-9 stuff pretty much went by the wayside. Well...I guess I've done two things here...one...show how old I am, and two, show how much nostalgia I have for those 'good old days'. Sorry if my ramblings bored anyone. Rick Bensene The Old Calculator Web Museum http://www.geocities.com/oldcalculators