A week or two ago, we got Kaleidoscope to run on the PDP-12! We haven't found and repaired any broken flip chips. So, either all the "percussive maintenance" we've been doing in the process of testing flip chips has paid dividends, or -- more likely -- I tried to run it in 8-mode last time... it is a LINC program. Anyway, enjoy these GIFs. #umdpdp12 #pdp #pdp12 #dec #retrocomputing #vintagecomputing #minicomputer

A couple weeks ago, for no apparent reason, the hits to our PDP-12 channel on YouTube went through the roof (for us). Then, as quickly as they came, they went! Oh well, glad I didn't quit my day job, and as @spacehobo pointed out -- the PDP-12 is *part* of my day job. 🤣 💚 #umdpdp12 #retrocomputing #pdp #pdp12 #dec

Ever wondered how to turn your 1970s-era PDP-12 minicomputer into a manual musical instrument, kinda like a really crappy theremin? Well, wonder no further! In this video, I provide the source code and performance technique information necessary to do just that! https://www.youtube.com/watch?v=HHepkRo7yRI

#umdpdp12 #pdp12 #pdp #retrocomputing

Ever wondered how to turn your 1970s-era PDP-12 minicomputer into a manual musical instrument, kinda like a really crappy theremin? Well, wonder no further! In this video, I provide the source code and performance technique information necessary to do just that! https://www.youtube.com/watch?v=HHepkRo7yRI

#umdpdp12 #pdp12 #pdp #retrocomputing

@jyrgenn Well @tastytronic has been doing that with the #umdpdp12 occasionally, and I've seen microcomputer repair channels like Adrian's Digital Basement do that with socketed ICs sometimes (usually with a bit of IPA or Deoxit to help clean the contacts out).

My friend @spacehobo saw our PDP-12 wallpaper in the background of one of our videos and wanted a downloadable one, so here's two of them in 1080p. His interest has inspired me to make higher-res versions available in multiple DEC liveries. We also have a special PDP-12 version based on the nameplate at the top of our machine, but it's not ready for the limelight. Enjoy, and stay tuned!

#umdpdp12 #pdp #dec #retrocomputing #vintagecomputing #wallpaper #pdp12

An M117E (left) and an M117C (right). The pinouts and logic are the same, but the etch (the traces) and chip layout are different. We think the rev C cards may have been put into our machine as part of a repair.

#umdpdp12 #dec #pdp12 #pdp #vintagecomputing #retrocomputing

The #umdpdp12 is serial number 435. According to this 1978 document from #DEC, the total number of #pdp12 #minicomputers ever produced should be 765: http://s3data.computerhistory.org/pdp-1/dec.digital_1957_to_the_present_(1978).1957-1978.102630349.pdf

I wrote a short series of help commands in #PunyInform for an #InteractiveFiction project. I wrote a short `intro` verb, a longer `help` document with the most common verbs needed to win the game, and a `stuck` verb that tells the user not to panic before advising on strategies for solving the puzzles.

I then decided to remap the StrongSub verbs over to my new StuckSub, so that it can catch anyone swearing at the game in frustration.

And yes, I included the #umdpdp12 #easteregg, where they found a command log of someone swearing at "this stupid chunk of germanium". I decided to make the help system replicate the #os8 error message in honour of this moment in #pdp12 #VintageComputing history.

Flip Chip Testing Progress!
https://umdpdp12.blogspot.com/2023/01/flip-chip-testing-progress.html?m=1

#umdpdp12 #retrocomputing #vintagecomputing #dec #pdp

The nameplate on our PDP-12, found inside the case. #umdpdp12 #retrocomputing #vintagecomputer #pdp #pdp12 #dec

OK, so where did all of this #LINC and #pdp8 stuff from this whoooole thread end up? Well, Dick Clayton from #dec explains in this short interjection at the DigiBarn event:

https://youtu.be/xT_5PcrVI9Q?t=5810

Basically Digital made a weird hybrid LINC/pdp8 system called the LINC-8, but it wasn't that great. So while he was on jury duty, he sketched out the Right Way to do it so that the system could switch between "8 mode" and "LINC mode" *in software*. The result was the #pdp12, which sold more units than all the previous LINC systems combined.

And that takes us to tonight's thread from @tastytronic, where the #umdpdp12 has just had its first successful verification tests of some of its 60-year-old flipchip cards: https://teh.entar.net/@tastytronic/109644812161500698

Special bonus: a picture of a double-wide M706 (rev. K) teletype receiver card under test.

#umdpdp12 #RetroComputing #VintageComputing #DEC #pdp #pdp12 #FlipChip

Finally, here's a glam shot of the FCT with an M617 installed. Thanks for joining me on today's project! Special thanks again to @neale and @ckape for the hardware donation, which saved this shoestring project close to $200.

Major thanks to Vince Slyngstad for producing Warren's design, making it RPi-compatible, and making a 3D-printed base -- not to mention selling me this kit pre-assembled -- this is a pretty sweet package and will go a long way towards helping us keep the our PDP-12 up and running for years to come.

If you're interested in learning more about our PDP-12, or donating to the fund supporting this project, please see https://umdpdp12.blogspot.com/ or check out our videos on YouTube: https://www.youtube.com/playlist?list=PLHnc49MScQBBIlVIirpZ1Zjdh91U5Q6-6

#umdpdp12 #RetroComputing #VintageComputing #DEC #pdp #pdp12 #FlipChip

Finally, here's a glam shot of the FCT with an M617 installed. Thanks for joining me on today's project! Special thanks again to @neale and @ckape for the hardware donation, which saved this shoestring project close to $200.

Major thanks to Vince Slyngstad for producing Warren's design, making it RPi-compatible, and making a 3D-printed base -- not to mention selling me this kit pre-assembled -- this is a pretty sweet package and will go a long way towards helping us keep the our PDP-12 up and running for years to come.

If you're interested in learning more about our PDP-12, or donating to the fund supporting this project, please see https://umdpdp12.blogspot.com/ or check out our videos on YouTube: https://www.youtube.com/playlist?list=PLHnc49MScQBBIlVIirpZ1Zjdh91U5Q6-6

#umdpdp12 #RetroComputing #VintageComputing #DEC #pdp #pdp12 #FlipChip

Here's a video of the tester running a "fail stop" test -- testing the chip over and over again, stopping only on a failure.

#umdpdp12 #RetroComputing #VintageComputing #DEC #pdp #pdp12 #FlipChip

It works! Here's a picture of the fully assembled unit, with an M617 in and powered, and a successful test on the screen behind it.

#umdpdp12 #RetroComputing #VintageComputing #DEC #pdp #pdp12 #FlipChip

After a few tense minutes thinking the Pi was broken, I realized it just wasn't plugged in. Then, after a few tense minutes thinking the powered USB hub I bought for this machine was broken, I realized that it was plugged into the wrong port. Raspbian is now installing on the Pi. #umdpdp12

Here's a picture of the FCT bolted onto the 3D-printed base. #umdpdp12

Here's a picture of the upper and lower sides of the FCT as assembled by Vince.

Flip Chips are inserted into the card slots (one for single-width, both for double-width). The ICs are expanders for interfacing between the testing computer (originally from Windows 95 over parallel, but in this version between an Rpi0 and the FCT over GPIO pins). Single pins are for attaching probes if desired, and LEDs provide some status information. (Most of the information is provided by the application that interfaces with the FCT).

#umdpdp12 #FlipChips