| Edwin van der Geld and David Haas, both have a 10 character
dot matrix Multi Info Display (MID). They tried to interface a
PIC16F84 to the Display, but found that the communication was not
working. I compared the communications of the radio with the communication
of the PIC. I found that the original software (Dispv07.zip)
was to slow. Therefore I decreased the value of the timers that
determine the wait periods and this software update (Edwin van
der Geld V04.zip) solved the problem! On special request of Edwin
the program was altered, to only show the welcome message. This
version does not contain the RPM counter.
A version that runs the RPM counter is available here: Dispv08.zip
(Not tested yet!!!!)
This display can show ten characters however the program I have
made is for the 8 character displays. The display is backwards
compatible, so it will understand the 8 character communication
protocol. To take full advantage of the display the ten character protocol
need to be analyzed. Fabio has figured out the Ten
char protocol..
Photos by Edwin:
The welcome message.
Pushing both buttons for a few seconds starts the self test of the
display. This is a function of the display and not of the PIC!
Photos by David:
Removing the display from the dashboard.
There are two connectors at the back side. The smaller 12 pin
connector is used.
The front side of the PCB.
The backside of the PCB.
Running the old Version 7 of the software gave some unpredictable
results! And showed some new characters that my DID cannot show! Very
interesting!!!!!
The first three characters are Ok. But the rest..... Also David
reported that the new timings solved the problem:
The tachometer program working on a ten character display using the 8
character protocol. Of course we would like to use the full ten
characters that the display can show however that protocol was not yet
known by us. Later, Fabio has figured out the Ten
char protocol.
The display can also measure the outside temperature which is shown
here. The display itself uses the full ten characters. This measurement is not done by the PIC but solely by the
display!
I would like to thank David and Edwin, for the photos and their
work!
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