[Coco] CoCo temperature monitoring

[Roger Merchberger]

Rumor has it that Mark Marlette may have mentioned these words:
>Bob,
>
>Other than resolution being poor, you might want to consider scaling
>the value to a range. Better to use modern technology, thermistors are not.

Well, if the OP want's an "exact temperature" I'd agree, but if it's just 
the difference between "Whew. We're OK" and a "Holy Crap it's hot in here, 
come fix me!" I would think that scaling the input would work - there's 64 
distinct values on the A/D on each of 4 inputs.

I wanted to set up a CoCo as an automatic temperature / rotational control 
for (of all things) an egg incubator, that I've been designing in my head 
over the years. Chicken eggs need to be kept *very near* 99F, and even with 
scaling, I don't think the resolution would be fine enough for that, and so 
I'd go with a different solution as well.

Some of the bigger AVRs have built-in 10 or 12-bit A/D converters in them, 
and can be programmed from a simple bit-serial protocol over a parallel 
port interface.

>Quoting theother_bob <theother_bob at yahoo.com>:
>
>>Hey everyone,
>>ISTR an old article in Hot CoCo or TCCM about using the CoCo
>>joystick inputs to read the temperature using thermistors.

There's also chapter on just this very thing a book I have roughly titled 
(I'm paraphrasing) External Interface projects for the Tandy Model 1, 3 & 
Color Computer.

I think someone even scanned that particular book in & made it a PDF... but 
I can't find that right now... I might have that archived at home, but I'm 
not sure. Either way, I'll grab the book tonite & let you know the exact 
title & whatnot...

Laterz,
Roger "Merch" Merchberger

--
Roger "Merch" Merchberger   | "Profile, don't speculate."
SysAdmin, Iceberg Computers |     Daniel J. Bernstein
zmerch at 30below.com          |