One technique I sometimes use is to turn on a 50% duty cycle PWM pin, and hook that to the input I'm testing.May be a bit fast for this application, but at least it will show transitions.
A. Check the sensor with voltage to check if it have a 0 V for LOW and a 5 V for HIGH. If not well the system will not work.
The output voltage of the sensor is 2.5V.Is that the problem?? smiley-confuse smiley-confuse
The output voltage of the sensor is 2.5V.Is that the problem??