Why is a ’80s Computer
With Mac OS, Linux, and Windows dominating PCs
today, anyone can ask why the Color Computer (or, CoCo
for short) would be relevant. After all, we are talking about
a computer that existed in an official capacity from
approximately 1980 to 1991, whose stated maximum
RAM capacity was 512 Kb with a maximum processor
speed of around 2 MHz. Today’s computers — with
advanced processors from Intel and AMD, plus gigabytes
of RAM and storage capacity — tower over the Color
Computer’s meager specs.
Still, when the Color Computer first debuted it was
one of the most innovative PCs of its class. This new entry
into the home computer fray was based around the
Motorola 6809 microprocessor. The processor’s lineage
could be traced back to the PDP line of mini computers
made by Digital Equipment Corporation. The 6809’s
architecture, instruction set, and addressing schemes were
based on the PDP’s own.
This characteristic alone made the 6809 one of the
more advanced microprocessors of its time as compared
to others such as the MOS 6502 and the Zilog Z80 —
perhaps the two most commonly used processors in
home computers. In 1980, when the TRS- 80 debuted
using this processor, it was a big deal. It is thanks to
innovative technology such as the 6809 that we have the
powerful systems that we use today.
Let me share with you some of the exhibitors that
were present at last year’s CoCoFEST!
Cloud- 9 ( www.cloud9tech.com) is a company that
was founded in 1994 by Mark Marlette, and provides
hardware and software for the three versions of the Color
Computer. Noted products include an IDE interface that
plugs into the TRS- 80’s cartridge slot, memory expansion
modules, and NitrOS9. The latter is a full-fledged multi-user Unix-like operating system that runs on the Color
In addition, Drive Wire is available free of charge (as of
this writing) as a download from their site. Drivewire
information is found in the next section.
Cloud- 9’s display at the 2014 event included a few
decked out Color Computers showcasing their products.
This company has been busy supporting the TRS- 80
community by providing innovative products that bring
new technology and capabilities to this computer. They
have not been stagnant. Cloud- 9 reported updates to
existing products, as well as new development. Here’s a
brief summary of some of what has been going on.
The company is finalizing the design of miniFLASH.
This will be a product that will plug into the CoCo’s
cartridge slot (or Multi Pak Interface) and provide four
banks of 16K Flash memory to store ROM images. This
will eliminate the need to physically swap out ROM
cartridges or OSes. The 16K memory banks will be
selectable via software or directly by hardware.
Another product provided by Cloud- 9 is the DOS
adapter. This is a small printed board that plugs into the
Color Computer’s 24-pin EPROM socket and allows the
use of 28-pin EPROMs. The 28-pin EPROMs are easier to
find, plus they have an increased capacity over their 24-
The DOS adapter also incorporates a switching
mechanism so that the larger capacity EPROMs can be
divided into two banks, meaning that the user can burn
the contents of two 24-pin devices into the larger capacity
EPROM. Cloud- 9 updated this product recently, improving
its presentation by including a solder mask and silkscreen
on the printed circuit board.
A PS/2 keyboard adapter is another product available
from this company. The adapter is a CoCo keyboard
hardware emulator that allows the use of any PS/2
By Salvador Garcia
March 2015 55
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The Cloud- 9 exhibit.
Open-case CoCo showcasing Cloud- 9’s products.