Tim HalloranTo save my old plastic case from the power supply heat I setup my CoCo 2 to work off USB power from a modern USB connection on a power strip.
TRS-80 USB Powered Color Computer 2Tim Halloran2020-06-22 | To save my old plastic case from the power supply heat I setup my CoCo 2 to work off USB power from a modern USB connection on a power strip.
What works off 5V USB power: - Tuner output - CoCo VGA - CoCo SDC - Joysticks - Memory and CPU
What does not work: - Cassette port - Bit banger - Ed's composite mod (I ended up taking this out of my CoCo VGA machine)Fixing a DEC VT50 AA TerminalTim Halloran2025-05-10 | A video showing work on a DEC VT50 terminal from the mid-1970s. I've been at this for a while but getting closer to getting it to work.Repairing slow updates on a HP 8591A Spectrum AnalyzerTim Halloran2024-12-30 | This video shows getting an old HP 8591A spectrum analyzer going again. I had to fix the power supply (recap it) and then encounted very slow updates of the screen. About 30 sections per update. It turned out the memory card board had a bad chip. I ended up disconnecting the memory card board and got this old spectrum analyzer going again.CoCo 2 Restore Part 6 Tryout and Boxing It Up (Tandy Assembly 2024)Tim Halloran2024-09-14 | Part 6 of my project to donate for the no-minimum-bid auction at Tandy Assembly 2024. The idea is to create a ready-to-go "Dungeons of Daggorath" CoCo2!
This video demostrates how to setup the CoCo2 with a TV and power and then play Dungeons of Daggorath.
http://www.tandyassembly.com/index.htmlCoCo 2 Restore Part 5 Power with USB 5V DC(Tandy Assembly 2024)Tim Halloran2024-09-14 | Part 5 of my project to donate for the no-minimum-bid auction at Tandy Assembly 2024. The idea is to create a ready-to-go "Dungeons of Daggorath" CoCo2!
References:
github.com/hallorant/bigmit/tree/master/coco2usbUsing XY mode on a Tektronix 453 OscilloscopeTim Halloran2024-09-01 | It took me a bit to figure out how to use XY mode on my 453 oscilloscope. Hopefully this video will be helpful for folks trying to figure this out. It certainly will be helpful to me when I forget how to do this.
The Tektronix 453 was introduced in 1965 and produced through 1974. This one was a find. It was in great shape and really only required a lot of contact cleaning to restore.
More info on this scope: w140.com/tekwiki/wiki/453CoCo 2 Restore Part 4 Keyboard & 64k Memory Upgrade (Tandy Assembly 2024)Tim Halloran2024-08-09 | Part 4 of my project to donate for the no-minimum-bid auction at Tandy Assembly 2024. The idea is to create a ready-to-go "Dungeons of Daggorath" CoCo2!
http://www.tandyassembly.com/index.htmlCoCo 2 Restore Part 2 Take It Apart (Tandy Assembly 2024)Tim Halloran2024-06-17 | Part 2 of my project to donate for the no-minimum-bid auction at Tandy Assembly 2024. The idea is to create a ready-to-go "Dungeons of Daggorath" CoCo2!
http://www.tandyassembly.com/index.htmlCoCo 2 Restore Part 1 Unboxing & Testing (Tandy Assembly 2024)Tim Halloran2024-06-08 | Starting a project to donate for the no-minimum-bid auction at Tandy Assembly 2024. The ides is to create a ready-to-go "Dungeons of Daggorath" CoCo2!
http://www.tandyassembly.com/index.htmlPiKey-10 for the TRS-80 MC10Tim Halloran2024-05-24 | http://www.pikey.tech/pikey-10/ is the PiKey site with lots of cool information about it.USB-Powered Model 1 Keyboard (Tandy Assembly Exhibit Teaser)Tim Halloran2022-09-11 | A quick video of my prototype modification to a Model 1 keyboard unit to allow it to be powered by USB-A power. This unit will be on display at Tandy Assembly 2022 at the end of September.
Instructions: github.com/hallorant/bigmit/tree/master/model1usbTRS-80 Assembly Language: Toolchain InstallationTim Halloran2021-09-19 | This video shows how to setup a TRS-80 assembler and emulator on a modern Windows, Ubuntu Linux, or MacOS system. This video only shows how to download the software and get it running by setting up your path and such.
Timecodes
0:00 - Intro
1:37 - Toolchain software (how to check for updates)
2:13 - Windows installation
10:35 - Ubuntu Linux installation
21:57 - Raspberry Pi OS installation
27:09 - Mac OS installation
36:11 - Wrap upMaking a TRS-80 Cassette CableTim Halloran2021-09-18 | In this video we make a simple TRS-80 cassette cable that will work on a Model 1-4 or CoCo. We simply the cable to only send sound to the machine (typically from a laptop or phone). Apologies the camera work is not great but I hope this might help folks out if they need to create such a cable.
Timecodes 0:00 - Intro 1:48 - Build cable 8:07 - Test cableDigital VT100 Terminal ArrivesTim Halloran2021-01-17 | A quick video on a "holy grail" acquisition for me. A Digital VT100 terminal manufactured in Westfield, MA where I grew up and learned about computers.The Dirty Side of TRS-80 Collecting & RestoringTim Halloran2020-08-15 | I rescued a few Model 1s from the trash. What looked to me like a single Model 1 in the (badly photographed) ad was a whole collection including two complete TRS-80 Model 1s, expansion interfaces, floppy disks, and monitors. Plus a huge set of books and floppy disks. I show my initial cleanup with the vacuum and a damp towel.Lets Play Haunted House on a TRS-80 Model 1Tim Halloran2020-08-10 | I play through the Haunted House adventure game on a TRS-80 Model 1 computer. This is a very early text-based adventure game that ran on the original 4K (Level 1 Basic) TRS-80. The version I play through is the 16K "improved" version we created in the previous video. It avoids the annoying cassette tape loads when you die in the game and when you go to the second floor. I do show how to download trs80gp and run this game on a modern computer.
cassette file created in the previous video:
github.com/hallorant/bigmit/raw/master/src/haunt/haunt2.500.casLets create a better Haunted House game on the TRS-80Tim Halloran2020-07-22 | Hacking the Haunted House game for the Model 1 TRS-80 from 4K to 16K and making the game less annoying to play on a Model 1. Most Model 1s have 16K (or more) today. Just a fun little use of trs80gp for reverse engineering and trld to change formats.
Related work which includes disassembly and on-line version of the game (very cool).
http://computerarcheology.com/TRS80/HauntedHouseRunning my TRS-80 CoCo 2 on DC PowerTim Halloran2020-07-03 | An experiment running my TRS-80 CoCo 2 on DC Power. Demonstrates the system working with all the ports and tuner going. Shows the currents and voltages needed to power the system. Informing my work toward practical use of USB power. The noisy bench power supply is not practical.
Past USB power video:
youtu.be/qfa4Db2OwE8TRS-80 CoCo 2 Keyboard Teardown and CleaningTim Halloran2020-06-04 | I tear down a Color Computer 2 with a melted keyboard. I didn't find any videos showing this so I filmed it. Please be super careful if you try to do this because you can really damage your CoCo trying this.TRS-80 Model I VBLANK mod DemoTim Halloran2020-05-23 | The VBLANK mod allows software on a TRS80 Model I to see the beginning and ending of the vertical blanking interval (VBLANK). This demo shows off the mod with the simple example program from the TRS8BIT article.