Sir please make sure you have Servo library if you do #include At the top of your code and try compiling again.
Trigger pin sends out a signal (goes HIGH) every 500ms. This signal bounces off the obstacle The echo pin listens for a pulseIn. So what I did is to measure distance by dividing the duration / 2. (Time it took for the signal to travel from the trigger pin back to the echo pin) the answer you get you divide it by 29.1 to get your answer in centimetres.
??? very Good
please what do you mean, by source arduino, can you explain so i can understand? :)
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