Running and exploring the servo code

The code we are about to run can be found in the chapter10/servo.py file. I recommend reviewing the source code before proceeding so that you have an overall idea about what the file contains.

When you run the code found in the chapter10/servo.py file, your servo should rotate left and then right several times.

Let's look at the code, starting with some pulse width variables defined at line 1:

LEFT_PULSE  = 1000   # Nano seconds          # (1)
RIGHT_PULSE = 2000
CENTER_PULSE = ((LEFT_PULSE - RIGHT_PULSE) // 2) + RIGHT_PULSE  # Eg 1500

These pulse widths represent our servo's extreme left and right rotation.

Note that the LEFT_PULSE and RIGHT_PULSE values are in nanoseconds, as this is the unit used by the PiGPIO servo functions.

These values of LEFT_PULSE = 1000 and  RIGHT_PULSE = 2000 are the perfect world values that you will see sighted often. In reality, you may need to make...