SWTPC 6800/6809 Computer Review and History

[@atelierfan7502]

Thanks for the memories. I built a couple of "sweatpack" (SWTPC) systems way back in the early 80's. I made and sold a Radio Modem to Queensland Rail (Australia) based on the 6809. My own design PCB. Only 1200 Baud, but it was a full duplex error free protocol that I invented. Needed a voice channel - tones were Kansas city type of noise. 6850 ASCII data into a tone generator receiver - TCM3105. Radio transceivers were simplex however, so the TX relay got hammered; Send/Rx/Tx/Rx/Tx etc. as each packet was acknowledged! :-) Lucky the train order messages were short. Great video. I also met Dan Myers and 'Lucy' on a trip once to San Antonio - I was so wrapped up in the company I forgot to visit the Alamo on that trip!

[@andreasklindt7144]

There's something about 70's and early 80's computers that I can only describe as magical. I don't know, I was born in the mid 80's, so I missed that time completly, obviously. But there's is something about those machines that fascinate me.

[@toby9999]

I was dabbling with home built stuff in the 70's. Was a lot of fun. My first was based on a signetics 2650 8bit running at 2Mhz. I also built a TRS80 clone on wire wrap boards. The real coding fun started with the 6510 on C64 with color graphics and sound. A simple but capable CPU. They all used cassette tape for storage. Yes, there was something almost magical about those early days.

[@ropersonline]

6:15: Correction: These sixteen switches *EACH represented a bit.

[@cclark3452]

I love these stories and am shocked by how much computing history is in my hometown of San Antonio. Now I am seriously looking for my own project! Thanks!

[@robertstratton6498]

I very much enjoyed seeing you cover the history of these machines. I was familiar with the SWTP computers, as I programmed them for clients back in the day. I did not however, realize they made music synthesizers before they made computers. One hardware fact that I didn't hear in your video - Their terminals really were beautiful from an industrial design perspective. They were also MADE OF WOOD (at least the ones I used). You wouldn't know it to see them sitting there. The curves were sleek and really looked like something that might only be achieved through molding plastic. Then, if you tapped on them, or pulled the cover, it was a little bit of a shock to realize that someone had probably hand-sanded that work of modern art sitting on your desk. *A word of warning* for anyone collecting or restoring these - Some of the distribution disks for certain SWTP commercial software products were keyed to the serial number of the computer to which they were licensed. (This was mainly in the UNIFLEX environment - I don't know about FLEX or other OSes.) If you tried to install them on the wrong machine, I dimly recall them just hanging forever without actually telling the user that nothing was going to happen. As early DRM goes, it was brutal if you were trying to get work done and happened not to be paying close attention to your cabinets full of floppy disks. I never got to reverse engineer them enough to figure out where they were storing the machine ID in the hardware. True confessions: While I tended to mostly work as a programmer, I also sometimes found myself doing a lot of system administration work on certain jobs. _This_ was the platform that taught me as a system administrator to re-read my dangerous command lines twice and pause before hitting the return key. I once inadvertently formatted the install disk for something (might have been UNIFLEX) for an SWTP machine. Then I discovered that I couldn't just substitute any of the install disks for other, identical, machines at my site. Oops. These really were great, attractive machines. I'm not sure they get the title of all-time coolest 6809 boxes - that distinction may have to go to the Ohio Scientific Challenger 3P - Why not put 3 different perfectly good CPUs with different architectures in one box and let the programmer use any and all of them at their perverse whim? But I digress... Thanks for an interesting and informative video! Now I need to go buy a TRS-80 Color Computer. I blame you.

[@MrRussellibrown]

...and bat detectors. Don't forget them!

[@dmis888]

Привет из Росси. Я очень рад вас видеть. Давно не было новых видео. Желаю вам творческих успехов! Спасибо за видео. Hello from Russia. I am very glad to see you. For a long time there were no new videos. I wish you creative success! Thank you for the video.

[@BrianPicchi]

Thanks for the comment!

[@ihartmacz]

I am so happy to see an upload from you! Thanks for the great video!

[@BrianPicchi]

Thank you!

[@profpep]

Thank you so much for this. I am about to begin restoring a SWTPC 6800 system, with the CT1024, from a UK university. This one has the AC-30 tape interface.

[@pm71241]

OS/9 was fantastic. Ran it on a mc68020 ... great OS for small machines.

[@paulstubbs7678]

You've got me interested to see if I can get my SWTPC 6800 clone going, it's been years since it was powered. It's 95% my own design, in wire wrap, mimicking the SWTPC so that software cannot tell the difference.

[@clcswitcher]

I bought my SWTPc 6800 in late 1977. Parts started arriving in 1978, and by fall I had it working. I bought a Model 15 telex machine and wrote an ascii to baudot add-on to basic including delays for carriage return/line feeds and letters to figures shifts. My telex was capable of doing 60 baud but the polar relay was to slow so I had to increase the stop bit from 1.5 to 2 bits. Around 1980 I got floppy disks for it and by 1984 I was on the internet. I applied for a subnet and got one with 32 addresses in it. I never had DNS and used just IP addresses. I just had Telnet and FTP. Later they took away our class A and I lost my subnet. I wrote a checkers program in machine language and the moves had to be entered in hexadecimal. I got the gt6144 graphics card and wrote a Pac-Man like program for it. While my AC-30 doesn't work, I took all of the cassette data in S format and put them on a modern computer where I can load them onto my SWTPc. I'm still trying to get the floppy drives working.

[@BrianPicchi]

I know there has been some interest in programs written to take advantage of the GT6144. I'd love to see your Pac-Man program. Can you send over the S format code to my email. You can get it from my website.

[@clcswitcher]

@@BrianPicchi That program is on my one of my floppy drives. To make it go, you need an Atari 2600 joystick controller attached to a parallel port. I also modified the other parallel port with a 74121 to make it hold down the line for enough time for the 6144 to capture the data. My floppy drives don't work any more but I've heard that there is a program on windows that allows you to read 35 track floppies exactly. Do you know of a program that would work. I still have a 486 computer running windows 3.1 with a 5 1/4 floppy.

[@BrianPicchi]

@@clcswitcher Good question! I also could use a program that can read floppy disks and save them as a disk image. Very easy to do for other computers like the Apple II. If you find a solution, please share it with us.

[@jamesigou9033]

Good presentation. I used to read Creative Computing in the '70s and always found this system interesting. Later I owned several Tandy Color Computers and worked for a company selling 68K based OS9 systems. I have a soft spot for Motorola based systems, especially those based on the 6809 and 68K.

[@kevincozens6837]

The 6809 is still my favourite 8-bit microprocessor. Wow! The Psych Tone. I remember that from Popular Electronics magazine. I had forgotten about it. I had been tempted to build one back then but never got around to it.

[@chasonlapointe]

I'm so happy to see you well and back posting new videos!

[@AppliedCryogenics]

Loved the video. That's one gorgeous system and an enviable collection. I have a little homemade HD63C09 board on my desk which runs at 3.58 MHz and runs a stripped-down version of CoCo Extended BASIC via a R65C51 UART. I would so love to get a proper OS working, along with some file storage and better onboard development tools.

[@GeeWillikersMan]

The Heathkit Hero 1 robot used the same Molex connector system. Ran a 6808, too.

[@logicone5667]

I thought you were dead or just gave up on KZbin.. Thanks for a great video!

[@F4LDT-Alain]

Great video. Please show us UniFLEX which uses the real power of that machine with the Dynamic Address Translation. I've had my first encounter with Unix (well, something close to it) on a French SWTPC 6809 clone called the Goupil 3. Here I am some 35 years later, as a so-called Unix/Linux "expert" and systems engineer. UniFLEX has taught me what a real multi-user, multi-tasking O/S on a micro could be. I really miss the sound of it badly shaking the 8" disk drive at boot time before spitting out that "++ " prompt...

[@richardclarke376]

excellent video. I was around at that time, yet I keep finding computers I'd never heard of like this SWTPC, and also the Warrex Centurion!

[@TEK-Vectors]

Great video! Very interesting historical background!

[@malfattio2894]

What a great looking machine

[@RetroMarkyRM]

beautiful, beautiful machine...when machines had character and aesthetical appeal!

[@peberdah]

I miss SWTPC at that time, I got a friend who start a factory GESPAC focusing on Motorola chip and created the G64 bus standard, well known at CERN and nuclear research laboratories...

[@DaytonaRoadster]

good to see you again

[@techwizardmike]

This was excellent, thank you

[@leonardoantonio8756]

When you attended comic con, did someone mistake you for bruce campbell?

[@douro20]

Were there any video cards made for this computer?

[@jvburnes]

Awesome video. You must have been a little kid when this was all happening (or not even born). I was in high school. I remember the SwTPC 6809 ads in BYTE magazine. I've recently been playing with the System09, an SWTPC 6809 implementation for FPGA soft circuitry so that took me here.

[@mheermance]

Interesting, I've never heard of this company before, but it looks like a really nice system.

[@BrianPicchi]

I discovered them completely by chance when I picked up one of their systems several years ago in a small bundle. The more I discovered about them, the more I came to really respect their products.

[@garywilkinson5887]

Does anyone know the model number for that terminal screen, it’s amazing looking!

[@garywilkinson5887]

After a bit of research the terminal is an SWTPC 8212, rather than the SWTPC-82 mentioned in the video.

[@wa4kdc]

@@garywilkinson5887 Right! While the CT-82 & the 8212 were identical inside, the CT-82 is a much fuglier piece of hardware! I know, I have one! Always envied those who waited for the 8212! Far as I know the CT-82 was the first "intelligent terminal" period. It had a 6802 driving a 6847? (6845?) CRT controller and that made it much more capable than anything else money could buy at the time! Gary Kay & Joe Deres did some amazing work at SWTPc back in the 1970's.

[@blakekarbon9428]

Where did you find it!

[@joelavcoco]

Does anyone know if OS-9 LII was actually available for the SWTPc 6809? I know LI was, and LII was available for the GIMIX. The Evenson emulator has disk images of LI, but not LII. I have an SWTP 6809 (parts of 2 different ones) which does have a DAT circuit for up to 1M RAM, so it certainly _could_ have run LII.

[@BrianPicchi]

I believe so, but only on later models of the 6809. The S/09 and GIMIX computers were capable of addressing much higher RAM than the 6809 69A and 69K, for example.

[@wa4kdc]

Yes, it was. L1 was for machines with 64k (or less) RAM memory. L2 required machines with >64k RAM and the DAT thus was a much more powerful OS.

[@joelavcoco]

@@wa4kdc Any idea if there are extant disk images? All the ones to be found in the usual SWTPc repositories are LI only. There are LII images for GIMIX machines, but at least some of the GIMIX CPU boards are significantly different from (more sophisticated than) the SWTPc CPU boards.

[@joelavcoco]

@@wa4kdc And yes, I've used LII on the CoCo 3, and it's very nice. LI in 64K can be a bit cramped.

[@wa4kdc]

@@joelavcoco Sorry, I have no idea as I was a part of the Flex world at the time.

[@logansreplicas]

Didn't I see this video posted like 3 to 4 weeks ago?

[@BrianPicchi]

I re-posted it with the audio fixed, so it is more audible.

[@singletona082]

Regardless of my poor eyesight I like that terminal.

[@youreale]

Fascinating.

[@meismagiic4779]

How do you screen cap an old computer?

[@BrianPicchi]

Terminal Emulators. I mostly use the TeleVideo950 Emulator by Michael Evenson if I'm just playing around and testing. For file transfers I use HyperTerminal.

[@BrianPicchi]

I also use the SWTPC 6800/6809 Emulator by the same person mentioned earlier.

[@neilcherry6452]

@@BrianPicchi I've been playing with SWTPCmemulator and I have UniFLEX running on it. Still trying to learn to create a new bootable DSK file. I worked with the 6800 the CT-64 with FLEX and a Gimix Ghost with OS9 Level II (in 1984). The Ghost allowed us to have 6 people use the system plus 2 printers and a news feed. I loved the Ghost and I wish I had one. I have 3 Corsham Tech boards. I'll be setting up FLEX on the 6800 replica, NitrOS9 on one of the 6809's (moded to 1M ram) and the last 6809 (moded to 1M of ram) will get UniFLEX. I can't afford the real things. :-) I'm working on getting the 6809 UniFLEX env completely working and accessible from Linux. Have you found any 6809 UniFLEX documentation? I have the 6809 UniFLEX source and the 68K documentation. I'm reverse engineering the rest so I can rebuild everything and accessible from Linux.

[@BrianPicchi]

@@neilcherry6452 I love hearing how these old systems were used, so thanks for sharing that. Most stories with GIMIX involve multiple users sharing the system and using OS9-Level II. My experience with the 6809 has been almost exclusively with FLEX. It is a wonderful OS. I have only scratched the surface on UniFLEX, but I am very intrigued by your project and would love to hear how it progresses. Be sure to send your question about documentation to the FLEX User Group. They are super helpful and answered some of my programming questions.

[@paulstubbs7678]

Firstly, assuming something like a SWTPC etc, they talk serial, so just use a PC as a terminal. If you cannot get that to work - current loop interface, weird handshaking (highly unlikely) or it requires a terminal emulation that's hard to find a PC emulator for, then sniff the video from inside the terminal. Internally a lot of terminals drove the screen using composite video, or separate H, V sync and luma, that can be combined into composite, then all you need is a comp video capture device on a modern PC. Failing that, there is a raspberry pi based converter out there that takes in multiple variations of video and outputs HDMI, this was primarily made to allow old machines to talk to modern TV's and monitors. then all you need is a HDMI capture dongle for your PC/MAC.

[@robertgijsen]

Wow, who would've thought that was year 2k compatible!

[@djmips]

The Kurgan... oh you mean Mr. Krabs!

[@MichaelRusso]

Nice!!!!!!

[@tenminutetokyo2643]

Someone should make a retro kit PC case shaped like this with a small LCD built in.

[@Godzilla_Jesus]

LMNC sent me

[@inspectorfegit]

Came here from Look Mom No Computer :D

[@seanholmes8290]

there is a c64 still being used to balance drive shafts.

[@askhowiknow5527]

They can’t confiscate it...