cntntn:
I've made a circuit to detect electrical pulse from spark plug wire.
To test it I've made a simple program that every second check the sensor value and turn on a red LED if sensor value is HIGH and a YELLOW LED if RPM ( = (1/time)*60000) ) is over 4000. The 2 LEDs works, but when I try to connect arduino on serial monitor, when the engine is running connection is lost, but the LEDs still light up.
I have that problem with serial monitor
I thought there might be some short-circuit or something like that...
Who can help me?P.S. If you need the circuit sketch I'll let you have.
You didn't by some chance use one of the serial pins to detect the spark pulse?