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Control Angle via Button Pushes. One button increases angle. Other decreases angle. Both light LED. Servo Control Using Analog Signal. Obtain “analog” input using analogRead () . Voltage, V. Voltage tells us how hard a positive charge is pushed between two different points.
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Control Angle via Button Pushes One button increases angle. Other decreasesangle.Both light LED.
Servo Control Using Analog Signal Obtain “analog” input using analogRead().
Voltage, V • Voltage tells us how hard a positive charge ispushedbetween two different points. • Something, such as a battery, is needed to createa voltage. Current, I • Current tells us the amount of chargeflowing throughsomething (similar to gallons per minute). • Current must have a path through which to flow. I = V / R Resistor: R V = 5, R = 5, I = ?
What Is the Measure Voltage? 5V 4V 3V 2V 1V 0V
Potentiometer • Voltage at wiper depends onposition along the resistor. • Voltage varies between ground(0V) and the supplied voltage(5V in this case). • Voltage various continuously(analog “signal”). WIPER
Conversion of Analog to Digital • Obtain “analog” input using analogRead(). • analogRead()returns a value between 0 (if pin at ground) and 1023 (if pin at 3.3 V). • Argument of analogRead()is the pin to read(only pins labeled ANALOGIN can be used). • Servo position varies between 0 and 180.Therefore, must divide analogRead()whatreturns by 5.68333 (1023 / 5.68333 = 180).
Control Angle via Button Pushes One button increases angle. Other decreasesangle.Both light LED.