TRS-80 Color Computer 1

The TRS-80 Color Computer 1 was the Tandy Corporation's first color computer sold through its chain of Radio Shack stores geared for the home computer market. Tandy was an early participant in the micro-computer market with it's business line of computers, TRS-80 Models I, II, III, and IV.

The TRS-80 Color Computer 1, (nicknamed the 'CoCo' by loyal fans of the computer), was designed to penetrate the home market which at that time was heating up with more entries with color capabilities. The CoCo 1 was initially released with 4K or 16K of user RAM and on later models expanded to 32K. There were 3 revisions of the CoCo 1 before the release of the CoCo 2 all with distinctive cosmetic differences. The first two came in a one piece silver-gray plastic case.

The earliest version, which is pictured above, came with a chiclet style keyboard and only 4K or 16K of user RAM. It can be distinguished from later revisions by the position of the Radio Shack logo above the keyboard, it is not centered but shifted to the far left, and a small 4K or 16K button on the lower right corner on top of the case above the keyboard.

The 2nd revision retained the chiclet style keyboard and silver case, but came with a whopping 32K of user RAM. This version can be distinguished by the positioning of the Radio Shack logo in the center above the keyboard and the absence of the 16K button on the top of the case.

The third and final revision of the CoCo 1 saw the end of the silver-gray color case, to be replaced with a white color case and gone was the chiclet style keyboard, replaced by an improved keyboard. By this time RAM memory was beginning to drop in price and this version of the CoCo 1 came standard with 64K.

On the rear of the CoCo are a number of ports and pushbuttons, starting from left to right a pushbutton reset switch, an RCA type plug for RF output to a TV, a select channel output 3 or 4 slide switch, a round 5 pin DIN, ( an acronym for the Deutshe Industrie Norm ) connector port for connecting a cassette recorder for mass storage, a round 4 pin DIN connector port for connecting a modem or printer, two round 6 pin DIN connector ports for connecting joysticks, and a pushbutton off/on power switch.

Unlike other one piece computers of the era the CoCo's power supply was built in. The norm was a large 'brick' like power module that added to the tangle of wires and confusion behind the computer.

On the right side is an opening for the expansion slot to insert ROM cartridges called 'Program Packs' or the disk controller for the single sided 156K Model 500 Disk Drive.

The 4K CoCo 1 in this exhibit was acquired at a flea market complete in its original box along with a model 500 disk drive.

System Architecture		Memory
Microprocessor	6809E	Standard on system board	4K (early models) or 16K
Clock speed	0.89 MHz	Maximum on system board	32k (early models) or 64K
Bus type	Tandy Proprietary	Maximum total memory	64K
Data bus width	8 - bit	Memory speed and type
Address bus width	16 - bit	System board memory socket type
Interrupt levels	N/A	Number of memory module sockets
DMA channels	N/A	Memory used on system board
Standard Features		Disk Storage
ROM size	8K expandable to 16K	Internal disk and tape drive bays	none
Optional math coprocessor	no	Standard floppy drives	none
Parallel port type	none	Optional floppy drives:	yes
RS232C serial ports	yes	* 5 1/4 inch 156k	up to 4 external
Mouse ports	shared joystick	* 5 1/4 inch 1.2MB	no
UART chip used	N/A	* 3 1/2 inch 720k	no
Maximum speed	N/A	* 3 1/2 inch 1.44MB	no
CMOS real time clock	N/A	* 3 1/2 inch 2.88MB	no
CMOS RAM	N/A	Hard disk controller included	no
Video & Graphics		Sound
Graphics Processor		Sound Interface device
Screen size - Col x Rows	32 X 16	Sound generation
Resolution - Colors/High	9 / 256 X 192	ADSR capable	no
Resolution - Colors/Low
Max colors	9	Programming language
Sprites or Missiles	no	Built in language	Microsoft basic ver 1.1
		Built in M L monitor	no
Expansion Slots		Keyboard Specs.
Total adapter slots	none	Number of keys	53
Number of 8/16/32 bit slots	none	Upper/lower case	yes/yes
		Keyboard cable length	N/A
Total I/O ports	2 joysticks/1 RS232c 1 cassette interface 1 game port
Physical Specs.		Environmental Specs.
* Height	3 3/4 inches	Operating voltage @ 60 Hz	105 to 130 VAC
* Width	14 1/2 inches	Maximum power supplied	0.26 WATTS
* Depth	13 3/4 inches	Power supply output - volts
* Weight	7 pounds 4 ounces	Power supply output - amps

Introduced	1980
Discontinued	1982
Release Price	$399.00