Christopher Mitchell
@kermmartian.z80.me
Director of Geospatial AI @nbcuniversal.com, CS Ph.D., founder @Cemetech, hardware and software hacker, distributed systems guru, lover of trains. Opinions are my own.
I think it's that time again.
November 10, 2025 at 2:21 AM
I think it's that time again.
Reposted by Christopher Mitchell
We woke up just before September ends: our August 2025 Projects of the Month is live. Tetrises, RPGs, hardware projects, for graphing calculators and beyond: see what our creative hobbyists have been making, and vote for the best: www.cemetech.net/news/2025/9/...
Projects of the Month: August 2025 | News | Cemetech
www.cemetech.net
September 29, 2025 at 10:23 AM
We woke up just before September ends: our August 2025 Projects of the Month is live. Tetrises, RPGs, hardware projects, for graphing calculators and beyond: see what our creative hobbyists have been making, and vote for the best: www.cemetech.net/news/2025/9/...
Another month, more progress towards constructing my full-scale train simulator, now with laser-cut hardboard to test out its 1:1 component layout: z80.me/blog/tsc-das...
Train Simulator Controller: Dashboard Prototyping, Part 2
My cardboard prototype of the central portion of a Class 80x dashboard allowed me to iterate to a laser-cut hardboard prototype.
z80.me
September 6, 2025 at 11:51 PM
Another month, more progress towards constructing my full-scale train simulator, now with laser-cut hardboard to test out its 1:1 component layout: z80.me/blog/tsc-das...
August 31, 2025 at 3:24 PM
Native code programmability (C/ASM) vanished from my dearly beloved TI-84 Plus CE calculators with an OS update in April, after irresponsible developers showed off embedding an ESP32 with a camera in a calculator to use it to cheat. The community just released a jailbreak: youtu.be/6MeHya0LJX8
Calculator Games UNLOCKED (2025)! TI-84 Plus CE Jailbroken, Again
YouTube video by KermMartian
youtu.be
August 30, 2025 at 5:04 PM
Native code programmability (C/ASM) vanished from my dearly beloved TI-84 Plus CE calculators with an OS update in April, after irresponsible developers showed off embedding an ESP32 with a camera in a calculator to use it to cheat. The community just released a jailbreak: youtu.be/6MeHya0LJX8
A Tail of Two Kitties.
August 8, 2025 at 1:58 PM
A Tail of Two Kitties.
A very accurate summary of my day today. #GreatestGathering #SoManyTrains
August 2, 2025 at 11:12 PM
A very accurate summary of my day today. #GreatestGathering #SoManyTrains
It may just be cardboard, but physical prototyping of my Class 80x train simulator at 1:1 scale has been very helpful in figuring out if I've gotten the size and layout right, not to mention reasonable for my desk: z80.me/blog/tsc-das...
August 1, 2025 at 9:33 AM
It may just be cardboard, but physical prototyping of my Class 80x train simulator at 1:1 scale has been very helpful in figuring out if I've gotten the size and layout right, not to mention reasonable for my desk: z80.me/blog/tsc-das...
Reposted by Christopher Mitchell
Less than seven years late, Cemetech's calculator-hacking exhibits at World Maker Faire 2018 - and what the loss of the Faire in 2019 has meant for showing off DIY, making, and hacking, inside and outside the calculator community. www.cemetech.net/news/2025/7/...
July 5, 2025 at 5:13 AM
Less than seven years late, Cemetech's calculator-hacking exhibits at World Maker Faire 2018 - and what the loss of the Faire in 2019 has meant for showing off DIY, making, and hacking, inside and outside the calculator community. www.cemetech.net/news/2025/7/...
In another project completed recently, I added UK-style horn controls to my burgeoning train simulator. 🔊 Thanks to my reusable CAN bus controller, it took an afternoon, mostly of soldering and crimping: z80.me/blog/tsc-hor...
June 22, 2025 at 3:51 PM
In another project completed recently, I added UK-style horn controls to my burgeoning train simulator. 🔊 Thanks to my reusable CAN bus controller, it took an afternoon, mostly of soldering and crimping: z80.me/blog/tsc-hor...
I've been writing 3D graphing programs for assorted graphing calculators since at least 2003. Now, after starting a 3D grapher for the TI-84 Plus CE and then pausing for eight years (coincidentally roughly the time since @geopipe.ai was founded), I've released it: www.cemetech.net/forum/viewto...
June 21, 2025 at 2:09 PM
I've been writing 3D graphing programs for assorted graphing calculators since at least 2003. Now, after starting a 3D grapher for the TI-84 Plus CE and then pausing for eight years (coincidentally roughly the time since @geopipe.ai was founded), I've released it: www.cemetech.net/forum/viewto...
When I next take the Caledonian Sleeper from London I'll be www.youtube.com/watch?v=4xgy.... 🚂🤘
GLORYHAMMER - On A Quest For Aberdeen (Official Lyric Video) | Napalm Records
YouTube video by Napalm Records
www.youtube.com
June 3, 2025 at 2:51 AM
When I next take the Caledonian Sleeper from London I'll be www.youtube.com/watch?v=4xgy.... 🚂🤘
Reposted by Christopher Mitchell
@kermmartian.z80.me and I are hiring for a staff-level DevOps engineer! @spackpm.bsky.social expertise is particularly welcome.
Staff DevOps Engineer
Company Description: NBCUniversal is one of the world's leading media and entertainment companies. We create world-class content, which we distribute across our portfolio of film, television, and stre...
smrtr.io
June 2, 2025 at 6:03 PM
@kermmartian.z80.me and I are hiring for a staff-level DevOps engineer! @spackpm.bsky.social expertise is particularly welcome.
Reposted by Christopher Mitchell
Jerry did I ever tell ya I was high school buddies with the guy who made DoorsCS7? Used to go over to his house to watch Stargate on SSD and play with his sick TI-84+
June 1, 2025 at 4:21 AM
Jerry did I ever tell ya I was high school buddies with the guy who made DoorsCS7? Used to go over to his house to watch Stargate on SSD and play with his sick TI-84+
Reposted by Christopher Mitchell
Trying to figure out why my Osaris won't read CF cards formatted by Windows, but will when formatted by my digital camera. I think it's the partition ID that's the issue that can be fixed in DISKPART with SET ID=06 (Windows uses 0E by default). Can even get my 1GB card to show up now!
May 29, 2025 at 2:19 AM
Trying to figure out why my Osaris won't read CF cards formatted by Windows, but will when formatted by my digital camera. I think it's the partition ID that's the issue that can be fixed in DISKPART with SET ID=06 (Windows uses 0E by default). Can even get my 1GB card to show up now!
My Train Simulator controller project continues as time allows. This time around, moving my CAN controller out of my air pressure gauge to allow it to fit into my dashboard, and the tribulations of learning to use lead-free solder: z80.me/blog/can-air...
Train Simulator Controller: CAN-Connected Air Gauge, Part 2
In my ongoing quest to build a physical cab dashboard to control Train Simulator, an important set of components are the gauges that tell me what’s going on with the train. As I build the dashboard in...
z80.me
May 25, 2025 at 4:30 PM
My Train Simulator controller project continues as time allows. This time around, moving my CAN controller out of my air pressure gauge to allow it to fit into my dashboard, and the tribulations of learning to use lead-free solder: z80.me/blog/can-air...
Reposted by Christopher Mitchell
What do a dithered puppy, row-major LCD graphics routines, and an update to a 29-year-old black-and-white arcade game have in common? They're all projects in Cemetech's April Projects of the Month update: www.cemetech.net/news/2025/5/...
May 22, 2025 at 2:14 PM
What do a dithered puppy, row-major LCD graphics routines, and an update to a 29-year-old black-and-white arcade game have in common? They're all projects in Cemetech's April Projects of the Month update: www.cemetech.net/news/2025/5/...
Achievement unlocked: realized I've actually been to today's Worldle, quite a few years ago for an academic conference.
May 15, 2025 at 1:09 AM
Achievement unlocked: realized I've actually been to today's Worldle, quite a few years ago for an academic conference.
Reposted by Christopher Mitchell
Better late than never: March 2025's hobby STEM projects on Cemetech covered the usual gamut, from games to an emulator to a MIDI player. Check them out, and vote for the best! www.cemetech.net/news/2025/5/...
May 2, 2025 at 12:31 AM
Better late than never: March 2025's hobby STEM projects on Cemetech covered the usual gamut, from games to an emulator to a MIDI player. Check them out, and vote for the best! www.cemetech.net/news/2025/5/...
What do you do when you want to build a train dashboard, but you don't have a train to measure? You figure out how to parse an obscure 3D model format, derive the planes the buttons lie in, and build a papercraft prototype. z80.me/blog/tsc-das...
February 1, 2025 at 3:07 PM
What do you do when you want to build a train dashboard, but you don't have a train to measure? You figure out how to parse an obscure 3D model format, derive the planes the buttons lie in, and build a papercraft prototype. z80.me/blog/tsc-das...
Reposted by Christopher Mitchell
yes this is a Lego flex.
IYKYK
IYKYK
January 27, 2025 at 7:54 PM
yes this is a Lego flex.
IYKYK
IYKYK
Okay, that works, and the RS-422 interface spits out...something. Now how do I talk to you?
January 27, 2025 at 5:47 PM
Okay, that works, and the RS-422 interface spits out...something. Now how do I talk to you?
Reposted by Christopher Mitchell
Your mission, should you choose to accept it: vote for your favorite Cemetech graphing calculator software project of 2024: www.cemetech.net/news/2025/1/... . You have plenty of options, including games, programming tools, math apps, and shells.
January 26, 2025 at 4:16 PM
Your mission, should you choose to accept it: vote for your favorite Cemetech graphing calculator software project of 2024: www.cemetech.net/news/2025/1/... . You have plenty of options, including games, programming tools, math apps, and shells.
Am I taking crazy pills?
January 9, 2025 at 3:34 PM
Am I taking crazy pills?
Reposted by Christopher Mitchell
