Interfacing a VR (variable reluctance) sensor

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi all,

This is my first Arduino project.

Has anybody got any hints and tips for interfacing a VR sensor?

I'm sure it must have been done before. It'll be used for working out RPM etc

James

2

I am planning to use this IC - Mixed-signal and digital signal processing ICs | Analog Devices

Seems to do the job I need. There will be 4 pulses per turn of the wheel - which works out at about 108 per second at 110mph or so. If I take it from the propshaft then it's around 400 per second.

Am I being naive thinking that something like this will work:

vrIn = digitalRead(vrPin);
  if (vrIn == 1 && pvrIn == 0) {
      if (micros() > pvrus) {
        vrus = micros() - pvrus;                  
        pvrus = micros();
      } 
      else {
        vrus = micros();
        pvrus = micros();
      }
}
  pvrIn = vrIn;