Tandy Color Computer 3 TRS-80 Memory Upgrade

[@CurtisBoyle]

Quick note: Later Coco 2's also had the Tandy badge (no Radio Shack, as earlier Coco 2's did). These are the only ones that might have a T1-VDG (the true lowercase version of the video chip) in it.

[@geekwithsocialskills]

Thanks for the tip on that. I'm still learning about the wonderful world of Tandy and the Color Computers.

[@fractalMD]

LCB knows EVERYTHING!

[@geekwithsocialskills]

You're not wrong Amy.

[@CurtisBoyle]

@@fractalMD Bwahahhahaaa! I have you *ALL* fooled!

[@geekwithsocialskills]

@CurtisBoyle done any soldering lately? LOL!

[@joelexplorestech]

I love that you have the new badge to correctly reflect the upgraded ram. Looks perfect!

[@geekwithsocialskills]

Me too! It's really cool that Cloud-9 made those badges to go with the memory upgrade. It really finishes off the look for sure! However if the badge wasn't available, having a stealth 512K RAM upgrade would still be cool LOL!

[@TJBChris]

Great video! The 512K upgrade really unlocks the potential of the CoCo 3. Those 512K badges really bring it home…I’ve got them on my upgraded 3s. Looking forward to the 2 XL. I never had one.

[@geekwithsocialskills]

The 512K memory upgrade and the soon to be done Hitachi 6309 CPU upgrade are must-haves as you know for the CoCo 3. I'm really looking forward to the possiblities with this machine now that I've got the upgrades in place. As for my 2-XL Robot, thank you for watching my video until the end LOL. That's a little easter egg for an upcoming video about him LOL!

[@tarstarkusz]

8:30 Just a little tip in case you didn't think of it.... I am incredibly disorganized and so whenever I make a modification to a machine, I tape the old parts inside the machine. That way, the old parts can never get "lost" so long as I have the machine. Great video. Hope you can get around to the CPU upgrade and show off the computer running some cool stuff.

[@geekwithsocialskills]

This isn't my first rodeo LOL. I will sometimes tape parts inside like you suggest, however over the years I've setup a really nice way of storing parts from doing upgrades, etc. At some point I'll do a video showing my work bench where I do a lot of these upgrades, repairs and how I store parts. As for doing the CPU upgrade, I've actually already done that mod. All I have left to do is the recapping of the motherboard which I'll be doing this weekend, so stay tuned for a follow up video in the coming weeks showing these updates and also showcasing some demos and homebrew games running on the machine.

[@NPrescott]

Ohh that badge looks nice!! Reminds me of the upgraded RAM stickers for the TRS-80 Model II and III. That sticker relocation looks factory. 😯 Thanks for the tip on the screws. Man, I have messed up before on commodores and made dimples on top 😬 Can’t wait to see whatever you do with this CoCo 3. I will get one eventually. I had the CoCo I & II but sold those years ago.

[@geekwithsocialskills]

The badge looks so good and even better in person. Cloud-9 did an amazing job on making it. Since you no longer has a CoCo 1 or 2 now, when you're able, if you only get one Color Computer, get a CoCo 3.

[@renatoamaral2029]

Great upgrade! Congrats! 👍👍👍💯💪

[@geekwithsocialskills]

Thanks 👍

[@anovaprint]

Clean machine. Look forward to seeing what that 512k can do.

[@geekwithsocialskills]

Thanks! You can find out more about how I got this CoCo 3 in an earlier SepTandy video with my Tandy related pickups, trades and donations from the past year.

[@ohioterran7374]

Awesome upgrade, awesome CoCo 3 and awesome video!

[@geekwithsocialskills]

Thanks for your kind words and watching my video! Much appreciated!

[@MrDave6309]

Coco3 is a beast with 512k.. nice machine to work on ..hardest part of the upgrade is removing the security sticker 😂

[@geekwithsocialskills]

I don't know, IMHO it's a toss up between removing the security sticker and the old glue under the original case badge LOL!

[@douro20]

There was one particular Nokia phone whose case components were secured with screws on either end, and all four screws were of different lengths!

[@geekwithsocialskills]

It seems back in the day companies did all sorts of wacky things with screw lengths and head types to try and keep non official service techs out of devices.

[@RetroTechy]

nice and easy upgrade, very cool

[@geekwithsocialskills]

It sure is! Thanks for watching!

[@Cybernetic_Systems]

Nice! I really need to order another raspberry pi to bring my CoCo Pi3 back to life. I stole the pi from it during the great pi shortage.

[@geekwithsocialskills]

You should! I remember the great Pi shortage of 2021-2022! Those were some rough times for sure!

[@tub8r]

Nice walkthrough on the RAM upgrade! A quick question on the video output - the TV image looks nice and crisp. Does it use plain composite or some sort of MOD or RGB output? And what is that rainbow ribbon cable for? Thanks!

[@geekwithsocialskills]

Thanks! The CoCo 3 RAM upgrade is a pretty easy upgrade to do. As for the video output, the CoCo 3 has a RGB port on the bottom which I'm using in this video along with a Switch-a-roo SCART cable. My monitor has a SCART connector but you can also use a SCART to HDMI box as well with this cable. Here's a link to where you can get the Switch-a-roo cable cocoman.onlineweb.shop/Switch-a-roo_SCART_cable/p7004829_20319861.aspx

[@BollingHolt]

Very nice! I still have to verify which memory expansion board I have. If memory (no pun intended) serves me, it's larger than the Triad board, so it's probably an older upgrade. Maybe I'll remember to look this weekend. I just hate the snipping because it's so permanent lol.

[@geekwithsocialskills]

You might have the official Radio Shack memory upgrade since they did offer one back in the day. According to the Cloud-9 folks the TRIAD memory upgrade runs 90% cooler than other 512K upgrades, uses 1/20th of the power and it's also half the size! As for snipping those two capacitors, even the official memory upgrade this needed to be done. If you ever want to reverse out the memory upgrade, you can easily just replace those two caps.

[@BollingHolt]

@@geekwithsocialskills I'll look at it at home and see. It probably would be worth it to get the Triad board just because of those benefits, not to mention the cool badge 😎

[@geekwithsocialskills]

At the time of writing this comment, the TRIAD upgrade board is $50 USD and IMHO totally worth the price. I'm not sure if they still include the replacement badge since I got mine about a year ago, so be sure to ask them when ordering if it's still included and/or available.

[@BollingHolt]

@@geekwithsocialskills I just looked at mine. It's branded Cloud-9 and actually has two 30-pin SIMMS.

[@geekwithsocialskills]

@@BollingHolt Cool! You have the earlier 512K SIMM version.

[@tarstarkusz]

You have to upload a video playing the "emulator" games for the coco3. Donkey Kong and Donkey Kong Remixed (IIRC) are near arcade perfect, especially for an 8 bit computer. There's also a Pac Man "emulator" as well. I'm pretty sure they all require the 512k upgraded model.

[@geekwithsocialskills]

Part of the reason I did the 512K memory upgrade and the soon to be completed Hitachi 6309 CPU upgrade was for running this updated games and ports on the CoCo 3, so for sure there will be some videos showcasing these games and demos.

[@tarstarkusz]

@@geekwithsocialskills Will existing software run at the proper speed with the upgraded CPU? I've read its faster even at the same clock speed without utilizing the extra features of the chip. Like if it's 20% faster, will it run original games 20% too fast?

[@geekwithsocialskills]

Existing software and games will run fine. The Hitachi 63B09E CPU is a pin-to-pin direct replacement for the 6809E found in all Tandy Color Computers which runs much cooler than the 6809E found in the CoCo. It contains additional CPU registers and an enhanced instruction set that will bring significant performance compared to the stock 6809 CPU.

[@CurtisBoyle]

@@geekwithsocialskills - it also defaults to "emulation mode", where all instructions run at the same speed as the Motorola 6809 (you do still have access to the new instructions and registers though). Turning on native mode speeds some of the instructions up (even with no code changes at all) so on average a program will speed up 15-20%. Do some reprogramming to use the extra instructions and registers and you can speed them up even more (Doing both I have Rescue on Fractalus running about 35-40% faster now, as an example)

[@geekwithsocialskills]

Rescue on Fractalus is amazing! Thanks for all your hard work keeping the Color Computer dream alive Curtis!

[@javiervidaurre6325]

Why, in a video titled "Memory Upgrade", would you use the "magic of editing" to edit out the actual installation of the new RAM PCB? That's the moment I was waiting for! I wanted to see where and how it connected to the motherboard, maybe even see the back side of the new RAM board (which you never showed us). I want my 6 minutes and 40 seconds back which is all I could take after your editing magic show.

[@geekwithsocialskills]

Starting at the 4:45 mark I cover exactly what you mention, showing where and how the memory upgrade board connects to the motherboard. I also showed the instruction page on "how-to" and specifically pointed out the areas being worked on. In future upgrade videos I'll work on showing more detail. Thanks for the feedback.

[@javiervidaurre6325]

@@geekwithsocialskills I was looking forward to the moment your hands actually pushed the new PCB onto the pin headers. I like your video till then, learned a bunch. Had a TRS-80 Mod III 48K. Never knew about the CoCo let alone the 3. 512k, wow. Checking out more of you videos, you present well..

[@geekwithsocialskills]

@javiervidaurre6325 I usually don't show that much detail in my videos since my hands usually get in the way LOL, especially trying to get the perfect camera angle. Basically I do a 30,000 foot view of various upgrades. I'm by no means a professional, just a hobbyist. Indeed 512K is a lot of memory. On my channel I later did a 2048K memory upgrade to the CoCo 3. Here's a direct link to that video kzbin.info/www/bejne/gmfToJx9gdKZaqM

[@ChadDoebelin]

Thanks Geek, I've got a memory upgrade to do on my coco3, but had not seen what was necessary to install it, or even open one up. Now I'm ready. What's a program that used extra memory?

[@geekwithsocialskills]

This CoCo 3 memory upgrade is probably one of the easiest upgrades I've ever done. I'm happy to hear my video will be of use to you for your memory upgrade. As for programs that use extra memory, a lot of the newer homebrew games take advantage of the extra memory. Back in the day with the official Radio Shack 512K memory upgrade I would assume it was mainly used for productivity software like spreadsheets, etc.

[@CurtisBoyle]

To answer your question - Quite a few of the games these days do. All the Williams arcade game transcodes (Defender, PacMan, Donkey Kong, Joust, Robotron) do, as do all of the Sierra graphic adventure games. Other games like Contras, Sinistaar also come to mind. And (my standard self serving plug here... lol) NitrOS9/EOU is designed for 512K or more (runs perfectly fine in 512k).

[@geekwithsocialskills]

The arcade game transcodes are amazing! They were a huge reason why I wanted to upgrade my CoCo 3 computer. As for NitroOS9/EOU, I hear that will set your hair on fire LOL!

[@tarstarkusz]

3:07 I don't know how they got away with these stickers. This is a violation of US federal law. They absolutely cannot void your warranty for opening it up or even making modifications unless they can prove your modification is the source of the failure. This was the law at the time. Yet, so many computer manufacturers did this. I guess most people would see the sticker and just give up because they didn't know it was illegal. I believe the law is called the Magnuson-Moss Warranty Act It is this law that allows you to use non-GM motor oil on a GM car or non HP ink/toner cartridges on an HP printer without voiding the warranty.

[@geekwithsocialskills]

You can't look at this with 2023 eyes. Back in the 1970s and 1980s we didn't have internet to look up these types of laws plus most of us had very little money, so the thoughts of hiring an attorney was not going to happen for something like this. People in present day are so quick to scream "lawsuit". IMHO these stickers just kept the honest people honest LOL. I voided my warranty early on with my Commodore 64 in 1983. I was more worried about what my family would say if I zapped my machine verses a repair shop giving me grief for opening up my computer back then.

[@tarstarkusz]

@@geekwithsocialskills I would think it would only take 1 person to file a suit or a few people to contact the FTC or whatever agency is responsible. Plus you have lawyers who like to drive around looking for violations of law or regulations. There are lawyers who drive around their area looking for technical violations of the ADA who then sue them. The 1980s version of those lawyers could go to user groups and take out an ad in the newsletter or something. But, you're right because they got away with it.

[@geekwithsocialskills]

Too bad you don't have a time machine. You could go back to the 1970s, 1980s and 1990s and rake in the cash filing all sorts of lawsuits.

[@tarstarkusz]

@@geekwithsocialskills Come on over and I'll fire up the Delorean! We're going back to good old 1985!

[@lindnertim]

First!

[@geekwithsocialskills]

Ha! Ok Amy! LOL!!!