The TRS-80 Color Computer started out as a joint venture between Tandy Corporation of Fort Worth, Texas and Motorola Semiconductor, Inc. of Austin, to develop a low cost home computer in 1977.

The Color Computer, referred to by many by its nickname CoCo (Color Computer), with its Motorola 6809E processor, was a radical departure from the Z80-based TRS-80 Models. Indeed the "80" in "TRS-80" stood for "Z80". For a time, the CoCo was referred to internally as the TRS-90 in reference to the "9" in "6809". However this was dropped and all CoCos sold as Radio Shack computers were called TRS-80 in spite of the processor change. The CoCo was produced between 1983-1986.

During the CoCo 1 production run, much of the discrete support circuitry had been re-engineered into a handful of custom integrated circuits, leaving much of the circuit board area of the CoCo 1 as empty space. To cut production costs, the case was shortened by about 25% and a new, smaller power supply and motherboard were designed. The "melted" keyboard from the white CoCo 1 and the TDP-100 style ventilation slots were carried over. Aside from the new look and the deletion of the 12 volt power supply to the expansion connector, the computer was essentially 100% compatible with the previous generation. The deletion of the 12 volt power supply crippled some peripherals such as the original floppy disk controller, which then needed to be upgraded, installed in a Multi-Pak interface, or supplied with external power.

Production was also partially moved to Korea during the CoCo 2's life-span, where many owners of the Korean-built systems referred to them as "KoKos". Production in the USA and Korea happened in parallel using the same part numbers; very few, if any, differences exist between the USA built and Korean built CoCo 2 machines.

Upgraded BASIC ROMs were also produced, adding a few minor features and correcting some bugs. A redesigned 5-volt disk controller was introduced with its own new Disk BASIC ROM (v1.1). This controller added the "DOS" command which was used to boot the OS-9 operating system by Microware.

Later in the production run, the "melted" keyboard was replaced with a new, full-travel, typewriter-style keyboard.

The final significant change in the life of the CoCo 2 was made for the models 26-3134B, 26-3136B, and 26-3127B (16K standard, 16K extended, and 64K extended respectively). Internally this model was redesigned to use the enhanced VDG, the MC6847T1. This enhanced VDG allowed the use of lower case characters and the ability to change the text screen border color. However, for compatibility reasons neither of these features were used and are not enabled in BASIC. Midway during the production run of these final CoCo 2s, the nameplate was changed from "Radio Shack TRS-80 Color Computer 2" to "Tandy Color Computer 2". The red, green, and blue shapes were replaced with red, green, and blue parallelograms.

KEYBOARD   Full-stroke keyboard, 53 keys. Arrow keys, BREAK, CLEAR, SHIFT (x2)
CPU   Motorola 6809E
SPEED   0,89 Mhz (1,8 Mhz by programming the clock generator)
RAM   16 KB, 32 KB or 64 KB, depending on models
ROM   8 KB (Color Basic), but later models had 16 KB (Extended Color Basic)
TEXT MODES   32 x 16
GRAPHIC MODES   256 x 192 (2 colors), 128 x 192 (2 and 4 colors), 128 x 96 (4 and 2 colors), 32 x 64 (8 colors)
COLOrsc   9
SOUND   1 voice (6-bit DAC)
SIZE / WEIGHT   9 x 35 x 37,5 cm
I/O PORTS   Expansion/Cartridge connector, two analog joystick connectors, cassette interface (1500 bauds), RS232 serial port, TV RF connector
OS   OS9 Level 1 with disk-drives

Our model number is the final production 64K version and has a model number of 26-3136A with a serial number of 2004824 and was very kindly donated by Ian Jones.

Ian, who also wrote software for the machine, gave us the following notes:

"I bought the computer from the Tandy store in Wolverhampton around 1985/1986 new but not working for £5 spares or repairs. It was the last one they had in the store, probably the last one anywhere in the country. I bought it as I had been using a Dragon 32 I had been given, and the Tandy was 64KB so could do more, but did everything the Dragon could using the same programs and hardware.

I took it home, took it to bits and found that someone had spilt coffee in the keyboard. I cleaned it out and it has worked fine ever since.

I spent many happy hours writing programs (games) until the early hours of the morning and finally decided to put it into storage when I found myself still writing programs as the dawn chorus came up and I still had to go to work the next day. I did not touch another computer until 1995 when Microsoft introduced something new.

Many of the programs I wrote such as Golf, Moon Lander, Helicopter Rescue etc are in the tapes I have sent you. Have fun with them, they still load."

Manufacturer: Radio Shack Tandy
Date: 1983

This exhibit has a reference ID of CH18510. Please quote this reference ID in any communication with the Centre for Computing History.