TRS-80 Fragmentation

Fred Cisin cisin at
Thu Apr 26 19:18:47 CDT 2018

On Thu, 26 Apr 2018, Geoffrey Oltmans via cctalk wrote:
> common architecture. Do you think that if they had, say, revised and
> extended the Model I system to color/80 column that the rest would have
> been mostly redundant?

D'ya mean like an automobile company making more than one model?  Surely 
there is no need for Toyota to make both a Corolla AND a Camry!

The Model 1 was a wild venture into a field that they knew little about, 
and didn't know what to expect.
Ask Allison about what they expected.
It turned out that what they made was surprisingly close to correct for 
people like US.
Well, other than 16 lines by 64 characters of B&W, and a memory map that 
was not compatible with CP/M.

But, that's not where they would expect the big money to be.

So, they made a bigger "business" computer, the Model 2, with 8" drives.
It could even run CP/M, for those who didn't appreciate Model 2 TRS-DOS 
(which is NOT closely related to TRS-DOS (by Randy Cook))

Then they upgraded the model 1 to reduce the cords and cables, and made 
the Model 3.  I don't know whether the resemblance to the Northstar 
Dimension was deliberate.

They made a 68000 co-processor for the Model 2, creating the models 12 and 

They needed a low-end machine with color, games, cartridges, etc. 
Following a Motorola applicatoin note, they made the "Color Computer".
Since it was solely for games, etc., and not intended to compete with 
their other models [HA!], there was "no need" for 80 column, no need for 
composite video, no need for a decent keyboard, . . .

But what about pocket computers, PDAs, calculators?  Have to come out with 
some offerings there.

Howzbout a tablet of some sort, for wannabe journalists?  Kyoto Ceramics 
had just the thing, ready for re-branding.

Oh, and then they modified the Model 3.  The Model 4 is the same, EXCEPT:
80x24 video, a "Control key" on the keyboard, memory map with RAM all the 
way, so it can run CP/M, AND, they changed it from battleship gray (they 
called that "Mercedes Silver") to white.

Model 4P is same, in a luggable case.
(The Elcompco earliest machines were a model 3 motherboard in a 
Halliburton attache case, until the 5150 came out)

Frankly, although I agree that they made MANY mistakes (such as not doing 
the 80x24 upgrade a lot earlier!), I think that it was a fairly reasonable 
suite of models.

Would they have been more successful if the model 2000 had been a PC 
clone, instead of "better than"?

Grumpy Ol' Fred     		cisin at

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