--- title: Tandy Radio Shack Color Computer 3 categories: - Computers types: - Home Computer origins: - U.S.A. years: - '1986' cpus: - Motorola 68b09e params: name: Color Computer 3 image: /media/museum/photos/tandy_color3_system_s1.jpg logo: /media/museum/logos/tandy_color3_logo.gif company: /companies/tandy-radio-shack company_name: Tandy Radio Shack specs: - label: NAME value: Color Computer 3 - label: MANUFACTURER value: Tandy Radio Shack - label: TYPE value: Home Computer - label: ORIGIN value: U.S.A. - label: YEAR value: '1986' - label: END OF PRODUCTION value: '1992' - label: BUILT IN LANGUAGE value: Disk Extended Color Basic 2.1 (Microsoft BASIC, with enhancements by Microware) - label: KEYBOARD value: Full-stroke keyboard - label: CPU value: Motorola 68b09e (uses an external clock generator) - label: SPEED value: 1.79 MHz (0.89mhz under RS-DOS for compatability with FD expansion unit) - label: RAM value: 128 KB (up to 512 KB. There were 1MB and 2MB upgrade boards as well) - label: ROM value: 32 KB - label: TEXT MODES value: 32x16, 40x25, 80x25 - label: GRAPHIC MODES value: 'Several graphic modes, the most interesting were: 320x200 (16 col.), 640x200 (4 col.), 640x400 (4 col. if 512 KB RAM)' - label: COLORS value: '64' - label: SOUND value: See comment below - label: SIZE / WEIGHT value: Unknown - label: I/O PORTS value: Tape, Composite Video, analog RGB connector for use with Tandy CM-8 monitor, 2 joystick ports, cartridge slot, RS232 - label: OS value: 'with optional disk drive : RS-DOS, OS-9 Level 2 was also popular' - label: POWER SUPPLY value: Built-in PSU - label: PRICE value: $219.95 (USA, 1986) tabs: - photos - hardware - connectors - emulators - links photos: - title: COCO 3 subtitle: '' text: '' image: /media/museum/photos/tandy_color3_system_s2.jpg - title: TOP VIEW subtitle: '' text: '' image: /media/museum/photos/tandy_color3_topview_s1.jpg - title: BOTH SIDES subtitle: '' text: Note the cartridge slot on the right side. image: /media/museum/photos/tandy_color3_sides_s1.jpg - title: KEYBOARD CLOSE-UP subtitle: '' text: '' image: /media/museum/photos/tandy_color3_keyboard_s1.jpg - title: UNDERNEATH subtitle: '' text: Stangely, the RGB connector is located underneath the computer. image: /media/museum/photos/tandy_color3_bottomside_s1.jpg - title: REAR CONNECTORS subtitle: '' text: |- From left to right: • Reset switch\ • Audio jack\ • Composite video jack\ • RF channel selector\ • TV/RF jack\ • Tape recorder I/O DIN socket\ • Serial I/O DIN socket\ • Right and left joystick DIN sockets\ • Power switch. image: /media/museum/photos/rearcon_s1.jpg - title: OPENED subtitle: '' text: The keyboard is simply put on the shell and connected to the motherboard by a thin flat cable. image: /media/museum/photos/tandy_color3_opened_s1.jpg - title: MOTHERBOARD subtitle: '' text: |- **(1)** Four 41464 chips hold 128 KB of RAM\ **(2)** TV/RF modulator\ **(3)** Motorola MC68B09EP microprocessor\ **(4)** ROM cartridge connector\ **(5)** 32 KB ROM chip holding the Tandy BASIC interpreter\ **(6)** Custom GIME chip, especially made for the CoCo3, handles graphics and text display, system bus and various I/O\ **(7)** Keyboard connector\ **(8)** Expansion card (mainly RAM cards) connectors\ **(9)** Motorola LSC81001 I/O chip\ **(10)** Motorola 6821 PIA (Peripheral Interface Adapter)\ **(11)** Power regulator and it's cooler\ **(12)** AC power transformer. image: /media/museum/photos/tandy_color3_mainboard_s1.jpg - title: THE BOX subtitle: '' text: '' image: /media/museum/photos/tandy_color3_box_s1.jpg - title: COCO3 MANUALS subtitle: '' text: The BASIC reference guide is missing image: /media/museum/photos/tandy_color3_manuals_s1.jpg hardware: - title: TRS-80 COLOR COMPUTER DISK SYSTEM subtitle: '' text: It includes single external disk drive (uses standard DS, DD 5.25” floppy) with plug in disk interface, and 92 page users guide. image: /media/museum/hardware/tandy_color1_fd500_2.jpg - title: FD-501 subtitle: 5''1/4 disk-drive text: |- This picture show the case housing a double disk-drive, the controler cartridge and the box. The cartridge has the "Microsoft Extended Color Basic 2.1" in ROM. image: /media/museum/hardware/tandy_coco_fd501-disk_1.jpg - title: PLUG AND POWER subtitle: Domotic hardware ! text: An incredible extension for any Coco computer ! It turns your lights and other equipment on and off at designated times. image: /media/museum/hardware/tandy_coco_plug-and-power.jpg - title: PLUG'N'POWER subtitle: 'Pic #2' text: This is the x10 (x-10) "Plug 'n Power Appliance and Light Controller" that goes with the cartridge of the same name. This can be used to program lights and other electrical devices in your home or office to turn on or off using the x10 protocol (you need to have x10 controllers on devices you would like to control) image: /media/museum/hardware/tandy_coco2_plugnpower_2.jpg - title: RS232 PACK subtitle: '' text: '' image: /media/museum/hardware/tandy_coco_rs232-pack.jpg - title: SPEECH & SOUND CARTRIDGE subtitle: '' text: '' image: /media/museum/hardware/tandy_coco_speech-sound-cartridge_1.jpg - title: SPEECH-SOUND PAK subtitle: cat. no 26-3144 text: '' image: /media/museum/hardware/tandy_coco2_speech-sound-pak.jpg - title: SERIAL TO PARALLEL CONVERTER subtitle: '' text: |- It is a serial to parallel converter (DB25 connectors). A sticker on the bottom tells of all of the DIP switch settings, and a little LED shows the power status image: /media/museum/hardware/tandy_serial-parallel_converter_1.jpg - title: 512K TURBO RAM subtitle: from Speech Systems text: This board installs in a coco 3 to give it a whopping 512k of ram ! image: /media/museum/hardware/tandy_coco3_speech-system-512k-turbo-ram.jpg - title: WICO JOYSTICK ADAPTER subtitle: '' text: The Wico TRS-80 adapter allows you to use Atari 2600 joysticks (and other various controllers using the Atari standard) on your Color Computer image: /media/museum/hardware/tandy_coco2_vcsadapt_1.jpg - title: TRS80 COLOUR MOUSE subtitle: '' text: '' image: /media/museum/hardware/tandy_coco2_trs80colormouse_1.jpg - title: TRS-80 TOUCH PAD subtitle: '' text: '' image: /media/museum/hardware/tandy_coco2_trs80-touch-pad.jpg - title: TANDY JOYSTICK subtitle: '' text: '' image: /media/museum/hardware/tandy_color1_joystick_1.jpg - title: GT-116 subtitle: Tandy graphic tablet text: A4 size. It is used for transfering pictures or drawings, and also as a menu pointing system. image: /media/museum/hardware/tandy_color1_tablet_1.jpg - title: VINYL KEYBOARD COVER subtitle: '' text: Suitable for models 2 and 3. image: /media/museum/hardware/tandy_coco2_plastic-cover_1.jpg - title: DC-2212 subtitle: 1200-baud modem with automatic dialing and answer text: '' image: /media/museum/hardware/tandy_color1_modem2212_s1.jpg - title: MULTI-PACK INTERFACE subtitle: Model 26-3124 text: The Multi-Pack plugs into the cartridge slot on the side of the Color Computer and allows up to four devices to be plugged into the computer at the same time. A switch on the front of the MPI allows to switch between the 4 ROM Paks. This can be done also with software commands. With the MPI, a disk drive, an RS-232 Program Pak, and a game cartridge could be used simultaneously. image: /media/museum/hardware/tandy_coco_multipack-interface_1.jpg - title: OLDER MODEL subtitle: '' text: '' image: /media/museum/hardware/tandy_coco2_multipack-old_1.jpg - title: OLDER MODEL subtitle: Box text: '' image: /media/museum/hardware/tandy_coco2_multipack-old_box_1.jpg - title: TANDY COLOUR PRINTERS subtitle: '' text: |- **CGP 220** : (left) 7 colours Inkjet printer\ **CGP 115** : (right) 4 colours plotter image: /media/museum/hardware/tandy_color1_printers_1.jpg - title: 'CGP 115 #2' subtitle: '' text: |- 4-pen color graphic printer.\ Cat. 26-1192A image: /media/museum/hardware/tandy_color1_4penprinter_s1.jpg connectors: - title: RGB CONNECTOR subtitle: '' text: |- Looking at the outside of the RGB out jack. **(1)** Ground\ **(2)** Ground\ **(3)** Red\ **(4)** Green\ **(5)** Blue\ **(6)** Polarity (No pin)\ **(7)** Sound\ **(8)** Hsync\ **(9)** Vsync\ **(10)** No Connection image: /media/museum/connectors/tandy_color3_con_rgb_s1.jpg - title: JOYSTICK CONNECTOR subtitle: '' text: |- Looking at the outside of the Joystick jack on the computer **(1)** Comparator input (Right-Left)\ **(2)** Comparator input (Up-Down)\ **(3)** Ground\ **(4)** Fire button 1, High when open, Low when closed\ **(5)** Vcc, current limited +5VDC\ **(6)** Fire button 2 image: /media/museum/connectors/tandy_color3_con_joystick_s1.jpg - title: SERIAL RS232 CONNECTOR subtitle: '' text: |- Looking at the outside of the DIN socket on the computer **(1)** **CD** Carrier detect (Status input line)\ **(2)** **RD** Receive Data\ **(3)** **GROUND** Zero voltage reference\ **(4)** **TD** Transmit Data Out image: /media/museum/connectors/tandy_color3_con_serial_s1.jpg - title: TAPE RECORDER CONNECTOR subtitle: '' text: |- **(1)** Remote control\ **(2)** Signal ground\ **(3)** Remote control\ **(4)** Input from recorder\ **(5)** Output to recorder image: /media/museum/connectors/tandy_color3_con_taperec_s1.jpg emulators: - title: TRS CoCo3 Emulator by Jeff Vavasour v.1.6B url: http://www.vavasour.ca/jeff/trs80.html#coco3 platform: MS DOS text: A very good DOS based emulator that the author kindly made freeware with the source code in hopes others can port it to other OSes and platforms - title: TRS-80 Colour Computer 2 Emulator url: http://www.vavasour.ca/jeff/trs80.html#coco2 platform: MS DOS text: This DOS emulator (freeware) will run original CoCo as well as CoCo 2 software - title: CoCo 2 Emulator v1.5 for MS-DOS url: http://www.bpwl.com/pub/ar/trs80/coco2-15.zip platform: Windows text: '' - title: CoCo III Emulator url: http://www.voicenet.com/~swyss/cocoemul.html platform: Windows text: '' - title: Virtual CoCo for MacOS url: http://www.maya.com/Local/phil/coco/ platform: Apple text: '' - title: Virtual CoCo for MacOS url: http://www.maya.com/Local/phil/coco/ platform: Apple text: '' - title: MOCHA url: http://members.cox.net/javacoco/ platform: Other platform text: TRS-80 Color Computer (CoCo) Emulator Written In Java - title: MESS url: http://www.mess.org platform: Multiplatform text: MESS emulates Coco systems, among many other computers links: - title: Cloud-9 url: http://www.cloud9tech.com/Order/index.html text: The place where you can even buy a brand new CoCo3 - title: CoCo Quest Color Computer Games and More! url: http://www.prowler-pro.com/coco/ text: '' - title: Coco Webring url: http://nav.webring.yahoo.com/hub?ring=CoCo&id=40&list text: It says it all ! - title: CoCo Zonz url: http://www.bat-soft.com/coco/ text: '' - title: Color Computer Links url: http://coco3nuts.tripod.com/ text: '' - title: Color Computer Transfer Utility url: http://home.netcom.com/~tlindner/CTU.html text: '' - title: NitrOS9 url: HTTP://NITROS9.LCURTISBOYLE.COM text: Various Coco webpages, including 100+ downloadable games - title: RadioShackCatalogs.com url: http://www.RadioShackCatalogs.com text: Here, you can actually/virtually flip-through the pages to view the content of every RadioShack catalog. - title: Sock Master's Web Page url: http://www.axess.com/twilight/sock/ text: Dedicated Tandy Color Computer 3 page, full of info! - title: www.coco3.com url: http://www.coco3.com text: The title speaks for itself ! It includes among many things, a Coco FAQ - title: Web Wiz CAPTCHA url: http://www.webwizcaptcha.com text: Discussion about Tandy computers comments: - author: Steve (USA) date: Thursday 20th January 2022 text: Website link is for Tandy CCR (Cassette Recorder) information. Also, does anyone know if the CoCo3 video output can all be used at the same time? (for mirror display output, such as the RF coax output + RCA composite output, and maybe the RGB as well? ) - author: William (USA) date: Tuesday 7th April 2020 text: Disk Extended Color Basic wasn''t available on any of the CoCo line without the addition of the Floppy controller and the included internal ROM that plugged into the 40-pin expansion slot or the Multi-Pack Interface (or equivalant.) Otherwise just Extended Color Basic was available for use. - author: Corey Lynch (United States) date: Monday 19th August 2019 text: Michael Devenney, I am definitely interested. please E-mail me at the.lynchster@gmail.com - author: Michael Devenney (USA) date: Saturday 12th May 2018 text: I have a Tandy computer color 3 new in the box, never used. The outer box is in terrible condition , but the computer is unwrapped and has been never used. Anyone interested? - author: Derrick Green (United States) date: Sunday 30th April 2017 text: |- This was also my first computer since I owned a 2600 Atari and NES game system back in 1987. Learning basic was fun on this system with the built in color graphics. I remember bagging my parents for the floppy drive unit shortly afterwords and was able to save the basic programs and run games like Kings Quest. This was truly a revolution for the time and even had a special color monitor that could be purchased. What I was especially impressed about this system is all the expansion options that were available. When I was younger growing up I could all the options at once but being able to upgrade the system was an advantage along with having the composite video connection to get started. One of my biggest regrets was selling my entire system for $50 USD and purchasing a 286 computer at the time. This system and the first IBM computer tough me a lot. The new generation of youth has a lot to be learned as we grew up in our generation. - author: Jack (USA) date: Thursday 1st October 2015 text: the Tandy was my very first computer. I spent hours of fun on it. back when you had to turn the little switch from TV to computer on channel 3 back then. I wish Ii held onto it now, it''sd be fun to mess around again on it. thanks for the fun., Jack - author: Jorge (NY, USA) date: Wednesday 6th July 2011 text: |- I have uploaded scans of the system manuals, in PDF on skydrive, the Public address is https://skydrive.live.com/redir.aspx?cid$c1a7e9824022ad17$resid$C1A7E9824022AD17!732 I have some of the most common hardware manuals there too, if you are looking for another manual, most likely I have it. The manuals are for all 3 Color Computers ( 1, 2, and 3) Schematics and repair manual included. Please archive these manuals, I don''t know how long I will keep them there, or add them to Old-Computers.com as a direct download. - author: Lez Anderson (England) date: Monday 27th June 2011 text: Does anyone know if the COCO 3 FPGA project has been put into a low cost ASIC chip... i.e. a single ASIC chip Coco 3... I''m wanting to use one instead of a PIC or embedded processor ... It would be great if I could get a single chip coco 3 with the functions of the coco 3 ( Enhanced ) and the functionality of a PIC... I''d love to buy one ... - author: Joel Ewy (USA) date: Wednesday 16th February 2011 text: |- The CoCo3FPGA SOC actually started on the Xylinx platform, and was fairly recently ported to Altera. My blog shows my build of the CoCo3FPGA, put into an old CoCo 3 case. If you want more info about CoCo3FPGA, see the Yahoo Group: http://groups.yahoo.com/group/CoCo3FPGA/ - author: Kenai Andrews (Canada) date: Tuesday 26th October 2010 text: Poke 65495,0 was for the Coco 1 and 2. The speed up poke on the Coco 3 was poke 65497,0 and the slowdown was poke 65496,0. - author: Marcos (England) date: Thursday 16th September 2010 text: I believe these are on a Altera DE1 board using a cyclone chip runnning at 25MHz. - author: Lez Anderson (England) date: Tuesday 14th September 2010 text: |- The Coco 3 is now on a single chip (FPGA, Field programmable Gate Array) running at 25MHz!! Anyone with more info on this please post a message.... - author: Keith Smith (Hardburly,Kentucky 41747) date: Saturday 10th July 2004 text: |- The 2 MHZ command was poke 65495,0.\ I still have several of these,1 inside of an IBM case.\ These machines still work great as a basis for a home security system,satellite descrambler and a way to monitor an automotive computer.\ BTW I still love playing the Kronis Rift. related: - /museum/tandy-radio-shack-color-computer - /museum/tandy-radio-shack-color-computer-2 oc_id: 109 source: url: https://web.archive.org/web/20230609154716/http://www.old-computers.com/museum/computer.asp?c=109 date: '2023-06-09' --- The "TANDY Color Computer 3" followed the [Color Computer 2](/museum/tandy-radio-shack-color-computer-2/). The CoCo3 came with 128K RAM, an analog RGB video port, enhanced 640x192 graphics capability, a 64-color palette and much more. (All ports contained on the CoCo 1 and 2 models were also available on the CoCo3, e.g. RS-232 serial, cassette, right and left joystick and a 40-pin expansion slot.) The built-in Language, named Disk Extended Color Basic 2.1, was a Microsoft BASIC with enhancements by Microware. It was similar to that of the CoCo2, but Microware added the commands/functions to take advantage of the higher resolution graphics and text. The CoCo3 was upgradeable to 512 KB RAM. (After-market RAM upgrades have gone as high as 8MB, with rumors that 16MB and 32MB RAM upgrades may also be possible). A **Multi-Pak** (a 4-port bus expander) plugged into the Expansion Slot allowed use of controllers for floppy disk drives, hard drives (MFM, RLL, SCSI and now even IDE), multi-port true RS-232 devices, MIDI units and much much more. As its microprocessor was still an 8 bit (strange choice when [Atari](/museum/atari-520-st-st-stm/) and [Commodore](/museum/commodore-amiga-1000/) were using a 68000), it couldn't access simultaneously to the 128k (or 512k), and thus used several RAM banks which could be switched (as the [Thomson TO8](/museum/thomson-to-8-to-8d/), or [MSX 2](/museum/msx-2/) computers).\ Unlike the CoCo and CoCo II the 3 had an interrupt controller. This did away with a lot of the timing loops used in its predecessors, and actually took some of the fun out of programming in Machine Language. Tandy made several prototypes of a Color Computer model IV but it was never released. --- **Contributors:** D. Francis