norm2 wrote:

This site( http://64.27.84.239/ ) has a 4x20 backlit module that accepts
power, ground, and serial data as inputs.  $99.

This is a high  price for a 4 by 20. DigiKey has them for near half that
price.
http://www.digikey.com

Thing is, with the Digi-Key version you get to write your own serial to
parallel convertor, make the board, and put it all together.  I know, been
there, done that, got the tee-shirt, lots of spare parts as well  (Most of
which were purchased from Digi-Key).  I have some display boards available
if somebody wants to use them rather than pay the extra $50.  Just remember
how long you are going to spend figuring out the code).  They are built to
use a PIC '56 chip, if I remember correctly.  The code that I wrote
(Parallax Assembler) was to implement an I2C serial interface, but the
display was intelligent such that it would all have to be re-written.  (But
you are welcome to it if I can find it).  I also have some boards that were
set up with thermocouple cold junction compensation.  These used the PIC
with the A/D ('71 or '74?) These worked OK, but there is an easier way to do
it.  We moved the cold junction into the water temperature sensor.  That way
the T/C voltage was a temperature delta above the water jacket temperature,
rather than using a temperature compensation scheme.  Things you learn
second time around...

Back to it, I still have a plane to build...

Bring all that stuff to Sun & Fun norm. I might collect it up and see what
we can use for a prototype.

Paul Lamar
 
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