Quote:
Originally Posted by dcb
Why do we care if the zener stabilizes? Is it causing greater than 5v spikes on the atmega (can you scope on the chip?) Would a smaller resistor better protect the chip? And why do you think the zener is reverse biased during the inductive spike?
|
Well the concern would be solely its high being near the slicer threshold of a 1 versus 0.
Zener diodes are reverse biased by design to operate in the "zener" breakdown region.
Data Point 1992 honda civic cx
#define vssPulsesPerMile 4100ul
MPH was within 2-3 of the gauge cluster. More fine tuning could be done to match them exactly. I'm not running OEM tires so I will probably do that calibration with a GPS unit. I thought of a neat feature to add to the program : basically something that would compensate for different size (diameter) tires than OEM.
I can hook a scope up to the car, what would you like to see?