The Gyro Boy project does contain several My Blocks in addition to the main program. I will explain these My Blocks later in the chapter. In the project, the main program is called 001. There are two separate parts of the 001 program. There is the main program, Loop M, which controls the robot, and the Control Loop, BHV, which looks for feedback from the sensors.

We will first examine the main program Loop. In the following screenshot, we can see an Infinite Loop block titled M. Inside the loop, several My Blocks are called to execute the various subroutines. Instead of one long horizontal line of blocks as shown in the previous screenshot, I have rearranged the Loop block M into several rows. In this way, we can view the entire code on one screen.

The main program loop M repeats each time the robot is set up upright to begin running. The RST My Block resets several variables that will be used in the program to zero, and also resets the Gyro Sensor, the motor shaft encoders...