PCs

Dinosaur sightings: The Radio Shack TRS-80 Color Computer (CoCo)

The Radio Shack TRS-80 Color Computer 2

Before Microsoft and Bill Gates took control of the personal computer market, personal computers such as the Radio Shack TRS-80 Color Computer (aka CoCo) were all the rage. The Model 3134 TRS-80 shown in this TechRepublic Photo Gallery, came with a whopping 16K or RAM memory. Our TRS-80 CoCo is slated for a Cracking Open Gallery in the near future.

About

Mark Kaelin is a CBS Interactive Senior Editor for TechRepublic. He is the host for the Microsoft Windows and Office blog, the Google in the Enterprise blog, the Five Apps blog and the Big Data Analytics blog.

102 comments
jeffjgale
jeffjgale

I still have a CoCo in working order, My first over the counter computer was a TRS-80 3, Worked like a charm, just loved writing in all that code from the latest Mag, still have some of these too. Oh for the good old days of Dos. Regards Jeff.

riquilee
riquilee

10 INPUT "WHAT IS YOUR NAME";N$ 20 ? A$;" IS A DORK. " 30 INPUT "WANT TO PLAY AGAIN (Y/N)";Q$ 40 IF Q$="Y" THEN GOTO 10 ELSE ? "YOU SUCK.";:END

rojee
rojee

THE FIRST HOME UNIX MACHINE THE FIRST HOME GAPHICAL interface {before the amiga} the COCO 3 with OS9 Level 2 had both. I had a 20 meg stepper hard drive with mine. The rainbow magazine had pretty much finished when this was happening

Universal Indie Records
Universal Indie Records

I had an MC-10 and then once I finally received my Color Computer 3 it was on. I used a basic compiler to compile the shareware games that I had created into Assembler and actually got a review in Rainbow magazine. THose were the days man.....

Leticia M.
Leticia M.

I learned to program in this one!!! nice memories!!! :D

lancent
lancent

I got mine for Christmas 1980. It came with a whopping 4K, but out the door you could have it upgraded to 16K. Then, there was the upgrade to 32K. However, they upgraded with 'defective' chips. They were actually 64K, but 5% of the chips had a defective half (always the same half). So, the tech magazines showed a way to crack open the computer (it voided your warranty), solder a jump wire from one point to another, and if you were one of the lucky 95% you would have 64K!!.

nightandday4
nightandday4

I asked for a TI 99 for Christmas, and I got this piece of crap. I will never forgive me parents for that. If I had the hammer of Thor and one of those, I'd go medieval on it.

ggarcia1942
ggarcia1942

Would you believe this.....I still have one. It's still in the box and never been used. It was given to me by my sister who bought it at a Radio Shack store that had been flooded by a down-pour that we had here some years ago. This computer was among many items that were put on sale. My sister bought one only because someone told her that everyone should have one of these computers. She put it away in a closet and years later gave it to me because she had no idea what to do with it. By the time she gave it to me it was way obsolete. I have kept it only for old goodtimes' sake. G Garcia

Zenith545
Zenith545

Although I have many affectionate memories of visiting Bulletin Boards and programming C and Assembly Language with the TRS-80 CoCo, the TRUE Dinosaur is sitting in my Closet. A TRS-80 Model 1. 4KB of mem, Z-80 processor, complete with catalog and manual. With TRS-80 CoCo, just loved running OS/9 from the 5 1/4 in. disks. Remember Rainbow Magazine?

dfrank_robinson
dfrank_robinson

My son cut his programming teeth on a CoCo with OS-9. He's a Linus professional now. I still have three of these machines and they're not for sale. I have wondered if this design could be miniaturized for a revival in "3rd world" environments. How much might they cost to produce? $30, $40? Collect some analog TVs and Bam! Power by solar or wind or bicycle?

robertlbernhardt
robertlbernhardt

Had a CoCo 1. Aftere xpanding the memory from 16k to a whopping 64k, I added a floppy controller and upgraded to the Unix based Microware OS9 operating system. With a pair of 3" (no, not the current 3.25) double sided floppies, nothing came close. Purchased a full suite of applications including database, spreadsheet, and word processor.

memphis10ec
memphis10ec

My TRS-80 had 4k of memory, a cassette tape drive, and b&w screen. But that's all that $1500 could buy back then.

ZTedster
ZTedster

Wow. The countless hours I spent on one of those, playing Dungeons of Dagorath on a ROM pack, programming in TRS-BASIC to find the perfect speaker enclosure, and trying to design a speech recognition chip. All with a cassette recorder as a hard drive. ...and that whopping 32K of memory...

smorg27
smorg27

Awe man I thought I'd never see this old thing show up. I had one and still have it, and in mint condition. I have the tape drive, 1200 baud modem cartridge, some games and joy sticks. All still work perfectly. I've had this since they came out with it, was my very first real computer.

michael.muir
michael.muir

I STILL have a working CoCo3 with 64k, a CM8 monitor, floppy disk drives, cassette unit, OS9 disks, utility & game cartridges as well as programs on cassettes, and stacks of Rainbow, Hot CoCo and 80Micro magazines. I set up everything while on vacation last year for testing and reminiscing. Aaah! GREAT memories!

jontout
jontout

Did anyone have an Oric80 with the 'Oric' key that wasn't connected, but only on the keyboard for symmatry?

tainos_cs
tainos_cs

I remember getting my first great COCO I, then II then III... The first upgrade was to 64Kram, followed by and Expansion Bay for the cartriges, the internal fan that ran off the bridge rectifier with a separate front panel switch so the machine had enough power to boot up from the EPROM, the front panel ON/OFF switch, 'ON' LED and reset button and pulling the RGB signals from the MC6947 video generator pins. The great upgrades were a 1200 Baud Serial Modem, went from the Cassette drive to two 5.25" 35 track 160k Single Side floppies. Programming in Color Basic v1.1 or use a C or Pascal Compiler or OS9, reading off the Rainbow or 80Micro magazines and saving to cassettes to find that I made a mistake somewhere and did not realize it until 10 minutes of tape loading went by... The peeks and pokes and the (if a=1 then b=9 else x=a+B). What a trip down memory lane. I still love fixing computers, still hate programming but will tinker with these all day long... By the way, TRS did NOT become Tandy, TRS Stood for Tandy Radio Shack. Later it became the Coco 3 with the 6309 Processor instead of the 1.2Mhz 6809E, from here to the first IBM compatible Tandy, the Tandy 1000... Wow the coco was fast...

OldER Mycroft
OldER Mycroft

I can remember staring into the window of a local Tandy store, lusting after one of those machines. Not because of the OS or anything, just because it 'looked' nicely designed and seemed 'sturdy'. What a plonker!

jed.gart
jed.gart

I started with an Exidy Sorcerer with a huge 48k memory in 1979. I still have it stored away somewhere. We had to write all our own programs in those days and load them to casettes.

rbkircher
rbkircher

The Altair (Bill Gates first system) was really the first geek computer along with, perhaps, the Heathkit. The Altair was also a kit computer -- 8085 and I built the 8" floppy disk drive for it -- had only 8k of memory and I wrote a word processor for it along with an accounting program and a payroll program -- all were used in my small business in the late 70's. I still have it in the attice -- complete with front panel toggles switches, etc. -- we did built the eprom boot for it so that you didn't have to toggle in the bootstrap loader. Those were fun days ;)

basilmac
basilmac

Great machine for the price, hated the use of a tape deck!

service
service

I bought my first one as a gift for my 10 year old son...(really!!!!) and spent half of Christmas Day trying to get a couple of games to work. (Forgot the "M" in CLOADM). Eventually this machine (with a floppy drive, of course) was used to build the newsroom contact data base (about 800 contacts) for a radio station I worked at. That was a long wait for it to do its sort to/from the floppy. Great memories too of hours of typing in Basic programmes to do simple tasks. Sure wish it was that simple now. . .

edeleon
edeleon

I wrote the draft of my thesis with this model. It is nice to see the pictures again. Esther De Leon MST - Rep. of Panama

Sereniti
Sereniti

Oh, the memories! This was my first computer, because a "real" PC was too pricey for a young family budget in the early '80s. My husband wasn't the least bit interested, so I had to scrounge the cash myself. First, I subscribed to Rainbow Magazine (I bet my ex still has a stack of 'em buried in the garage somewhere), then joined a local user's group once I finally made my purchase. It wasn't "a bunch of kids" then, either. I was the youngest member of the group, and I was 30! These were all middle-aged ham radio guys, electrical engineers, aerospace workers, and me - the lone housewife! There weren't many women - especially "grown-up" women with kids - who were interested in computing in those days. I was the only woman in that group - so naturally they made me secretary! The first thing I did after I unpacked & hooked up the CoCo was order another 16K of RAM. I'll never forget the thrill of poking the screwdriver through that little silver sticker that said, "WARNING: If you open this, you void the warranty!" (I'm easily entertained.) Thanks for bringing back the warmth and simplicity of that time.

michaelrhansen
michaelrhansen

Had one as a kid and still have it in the attic with the rs tape drive. Missing the rs tape drive cable though. :-)

mikebon088
mikebon088

I still have all three that my dad and I bought--a 16K that he bought new, a 16K extended that was a store display, and a 64k extended that we bought from a classmate of mine who went to Commodore. Still have them and they still work except for the keyboard on one.

joe
joe

Had one of these (and I had the Original Color computer in the grey case), Back then adding Disk drives were big, if you wanted more then one serial device you had to build a switch box. Memory upgrades were fun 64K was just swapping 8 chips, 128K required you to solder a second set of chips to the first and daisy chain them. When that was complete, with Software program called Carosel you were able to setup different memory zones and run programs in each zone. The easy days of computing.

lconsidine
lconsidine

No matter the name on the "Dinosaur PC" ... we all owe our collective careers to these early inovations ... look where we are today because ...

j.courtot
j.courtot

I have a Commodore CBM 3008, upgraded n 3032, with 2 versions of BIOS homemade !!! The war is re-opened between the coco and the CBM ... !

poppajohn
poppajohn

I had the first one in Oklahama City, OK. Went to Lawton to get it. Had a ton of money in it. It was 4k when I got it but I moved the internal jumper and went to 8k. What a speed demon.

veronika
veronika

Wow - we used to call the TRaSh 80's! I used one, and a commador 64 too in the mid 80s.

malcolm
malcolm

A bunch of remaining diehards still gather in Elgin Illinois every spring. The Glenside Color Computer Club is still sponsoring the event: http://www.glensideccc.com/

kwacka
kwacka

- some group was always just about to release a card/driver. The 3 was never sold in the UK; bought a second-hand one from USA, replaced RF unit, step-up transformer. OS9 - my first steps away from Microsoft.

C-3PO
C-3PO

LOL... all of this talk of dinosaur's... all of us making these comments were around and using these machines when they came out... scary - who's the real dinosaur :)

OregonLighthouse
OregonLighthouse

Nice, but I have to go one better... MY first Trash-80 Model III came with DUAL 8" floppies, an external five-megabyte hard drive (whatever would I do with all that empty space?), 16K of RAM, and a daisy-wheel printer, all for the bargain price of $10,000 (which, luckily, the school paid... I bought it from the teacher for $500 when they switched to Apple-IIe's). But then... my first-ever was a Heathkit build-it-yourself (don't even remember the name of it) that had 256 BYTES of RAM, no program storage ability (every program was hand-entered by switches on the front) and you had to interpret a bunch of red lights on the front to get your results... monitors and keyboards were for wimps!!! LOL Ah, memories... aren't they so sweet?

philrunninger
philrunninger

A R!!! A R!!! A R!!! A R!!! A R!!! A R!!! Ah! The memories. I found a Windows port of DoD on the web a while back. A couple of years ago, I brought my CoCo to a gaming party. It obviously couldn't compete against the PS2, but the guys got a good laugh at me hacking the spiders, snakes and trolls.

jocol
jocol

Many mods on the coco, extending the ram to 64K. Moving the disk controller out of ram using a switch to gain extra memory, composit video output. Even wrote a screen dump program and put it in the boot ROM, with my first programmer (which I still have).Wow, those were fun days. Even my first computer, TRS-80 Model 1 was fun. Remember missing two days of work when I first got it!

paulp575
paulp575

Anyone remember what you were told to do when a program could not be read from the tape???? "Turn the tape player upside down and then press play!" Can't remember how many times I did that. And it worked! My original CoCo was purchased in Dec 1979. Then went to the CoCo II; then CoCo III. Anyone remember that the CoCo 4 was NOT made by Radio Shack? Unfortunately after the CoCo 4, Radio Shack decided to discontinue selling the CoCo. From what I remember, it was their hottest selling item during the Christmas selling season! One trick I used to remember was to walk into a Radio Shack store and type in some command (can't remember what it was :-(; that would turn off the graphics (until a reboot). Then ask a salesman for a demo. When they could not to the demo, I'd show them the trick. Yes, those were the days!

ajrjjr
ajrjjr

I still have mine in the attic. I got it when I was in high school. Mine was the 64k extended version. I also had 2 joysticks, cables to hook to a cassette player, & a voice synthesizer. I can remember sitting there for hours typing in code just to see a picture of a red flower with a blue background! Ahh those were the days! lol

tim
tim

It amazes me sometimes that the TRS-80 doesn't receive the credit that it should for its place in microcomputing history. John Roach and Bill Gates hand selected the BASIC instruction set for the Model I cramming everything they could into a ROM that could only use 4K of RAM. This was in the late 70's, long before the Commodore or PC was a twinkle in a product manager's eye. Apple was still selling DIY kits when the TRS-80 was available for retail sale. I know lots of you had CoCo's. I sold 150 of them myself in December of '83 in Canton, Ohio. The one pictured is a later configuration as the early ones were Mercedes Silver and black and had chiclet keyboards. The white ones were made in about '83 when Tandy changed color schemes on the full product line.

davidtexas
davidtexas

Had an Assembly Language compiler for mine. Wrote the 'Life' simulation and some other graphics stuff for it. Great education.

wdg3rd
wdg3rd

The Mod 3 never had 8" floppy drives. (Well, not stock -- adapters can be built). Those were on the Mod 2 (single sided), the 16, 12 and 6000 (all double sided). The HDs for that line (I have a 2, a 6kHD and a Mod 12 taken for parts for the 6k in my basement) started at 8.4 Mb, SASI interface, later ranged from 12 to 70 Mb St506 interface (the 5 Mb drive for the 1/3/4 series was also a ST506 interface). I also have a Mod 1 (which wasn't called that when I started fresh out of the USAF, it was just called the TRS-80 until the TRS-80 Mod 2 came out in 1979) a Mod 4, a 4p and at least one of each major version of Color Computer, from a 4k Coco 1 to a couple of 512k Coco 3 machines. Oh, and a few Mod 100 notebooks which are still my favorite machines for typing on the train, since my aging eyes can read the 40x8 text and the keyboard is better than anything except those that came with the Tandy 2000 and the AT&T Unix PC. My null-modem cables are sacred artifacts. Oh yeah, I did training and tech support for several Radio Shack Computer Centers (11- series stores) from 1980 to 1986. Because they started shipping Xenix for the Mod 16 at the start of 1983, I never developed fondness for MS-DOS or Windows. Yet Xenix was a Microsoft port of the AT&T Unix code base. Oh, and the guy who said his first Color Computer was bought in 1979, the system was released (along with the TRS-80 Model 3 and the Pocket Computer One) in summer of 1980. Ward Griffiths

tronman
tronman

Uhh, in the 'late '70s' meaning 1977, Commodore's PET was available for sale and, emboldened by his sale of the BASIC which it ran, Bill Gates had just sold (for three times the price..) his BASIC again, to Apple, who then promptly released the Apple II. Tandy was for sure a pioneer though, and they don't get the recognition they deserve. Hell, it's taken 25 years for people to actually start acknowledging that there were other computers besides Macs and PCs. Even though Apple today would still be stoked to sell 17 million of anything bigger than an iPod, as C= did with the 64. Commodore actually beat Apple to the 1 millionth sale, with the VIC=20, but they both hit the million mark in a month or two of each other. Any idea how many CoCos Radio Shack sold? I've never heard anyone say.

C-3PO
C-3PO

Yeah, I had a few of these machines. I had an original silver model that I wore the silver plating off typing in code from magazines. (Eventually I scrubbed the whole front off of the thing to make it look like it was supposed to be that way - the black was very sheik) The 6800 microprocessor was a dream to program and I wrote several pieces of code on it in both basic and machine code... I even used it to test proceedures I used in college to build my own security system from scratch using a 6800 processor and similar I/O chips... those were the days. Life is far more complicated now! More fun in some ways, but I still wish I could have the flexibility I had in those early days to manipulate just about anything I wanted to...

tim
tim

Remember typing in hundreds of lines of code from 80Micro? We were threatened with termination if we had a copy of 80Micro in our stores. I ran an "18" department in NE Ohio and cut my teeth on these babies. Any old Shackers out there?

Namaggio
Namaggio

Having worked three quarters of my professional life with Tandy and Radio Shack, I know one thing for sure. Tandy never promoted the number of units produced, not even to management outside a closely-knit group of trusted executives. It had nothing to do with anything illicit, at the time; they were a very honest company. They felt that exposing the actual unit numbers would give the competition something to exploit. Tandy/Radio Shack only once took out an ad in the trade rags. They felt that that type of advertising was aimed at distributors and dealers. Tandy was a vertically integrated company who controlled their own distribution through a company owned chain of retail outlets and licensed dealers. The closest anyone ever uttered about this issue was Bernie Appel, the then president of Radio Shack, "we sold a ton to them."

carl.gaede
carl.gaede

I learned machine code in parallel with BASIC on this baby. But this was also a great hardware hacking platform. I bought one of the first CoCo Model I's when the came out for Xmas 1980. I performed all of my own upgrades to move from the original 4K memory to 64K, the maximum address space for the 6809 processor. Plus the expansion port in the side provided full access to the CPU, memory and computer subsystems. I finally used it as the development platform for a wireless weather monitoring station that I worked on for a senior project as part of a computer science engineering degree I recieved.

Ian Thurston
Ian Thurston

Ya, I'm an X-man from the Canadian 'Shack. I, too, hail from the era when you could know the guts of your computer by heart. Hell, I hail from PDP-8 days when you hand-toggled the binary loader ... Like most of my geek chums, I had the COCO ROM dumps, the schematics. Thought I knew it all. I worked at the canadian head office, and I still remember when the first multi-threaded apps showed up. It broke the hearts of some of the guys in tech support. I've enjoyed playing with some of the COCO emulators that are out there (as well as the C64s, Apple IIs and Macs.) Helps cure you of the nostalgia - because these ARE the good old days.

tim
tim

Heh, good to hear. I have a book review in Sept. '86. One of my first published pieces (as tiny as it was).

rscarazzo
rscarazzo

I collected the series of magazines from 1990-1983. Every new magazine was packed with information and I remember anticipating each new one. Some of the projects were peek and poke fun and others were soldering iron material. I made an interface cartridge from an old 8-track case and built a circuit board to attach just about anything to the CoCo. I had a coffee maker turn on by a assembler program that used the computer clock. Man, those were the days like you said, could find a schematic on just about anything made.