Anything's possible, of course, and when you haven't got access to what
you're working with in terms of the organization, it doesn't help you to
understand what their goals are. The unit we delivered, was rock solid,
though. It would handle diskettes like nothing Tandy ever delivered, even
much later, though much of the credit goes to the programmer who wrote the
low-level code. I avoided coding whenever I could, and, I guess, still do.
By means of a slide-switch, it changed the memory map such that hardware
appeared as hardware should, in one position for TRSDOS, and the other for
CP/M. We got paid in full, and promptly, so I guess the RS people weren't
disappointed. I don't know the history of the Model-1, I know they had a
much better prototype at their disposal than the production units they chose
to ship.
It always "hurt" just a bit to see them ship that piece of dirt when they
had such a decent option. The sad thing is, the marketplace proved we were
on the right track. People wanted to use the box for CP/M, so they bought a
"mapper" which, as an option, remapped the addresses to make the low-end ROM
go away and replace it with RAM. Somebody sold a video enhancement which
attempted to fudge the video around so it displayed 24x80, but I'd like to
have seen that at least once, and there were several "enhanced" data
separators on the market for the model-3.
As for the model 2, I never saw one of these that wasn't for sale.
Dick
-----Original Message-----
From: Sellam Ismail <dastar(a)ncal.verio.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Saturday, April 10, 1999 3:47 AM
Subject: Re: What if,... early PCs (was: stepping machanism
On Sat, 10 Apr 1999, Richard Erlacher wrote:
> The RS people had their heads wedged, probably due to politics. They
used a
> strange mix of parts, seemingly cobbled together
from various vendors'
app
> notes. Their FDC used a TI TTL VCO, a Motorola
phase detector, and a
> Western Digital controller chip. Additionally they used some wierd TI
clock
> generator and some other stuff I couldn't
justify. Their clock recovery
> circuit was pretty poor, i.e. poorer than average, and cost about 6x what
I
> was used to seeing. Their dynamic memory handling
wasn't any sort of
slick,
nor was their
video circuit.
Rumor has it the Model 1 design was stolen from a third party consultant
by a less than talented head engineer at Radio Shack, and purportedly made
into the production model, bugs and all, so its not surprising that other
RS hardware was designed shoddily.
Sellam Alternate e-mail:
dastar(a)siconic.com
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