Explanation.

[bstites82]

assuming that this is in the teleop, which is inside the robot main loop which executes aprox every 20 ms. ok so if you walk through the code, it feeds the 4 buttons into an array, then it uses a boolean to number conversion to return the array index of the button that was pressed, then it checks to see if the array index of the button pressed was greater than 1(which i assume zero is the default case). it also writes the index value of any button that was pressed to a global variable called arm binary. then it feeds the results of "was button pressed" >1 to a select function, where it compares the index value of button pressed>1 to the global variable arm binary. now if a new button was pressed, and was greater than one, it moves to the case that corresponds with the index array of that button (ie.. top row, middle row, ect). and feeds the appropriate values to the pid controllers for the desired position. if the loop iterates and a button was not pressed then it executes the value read from global variable arm binary and stays at whatever the last position was (ie.. top row, middle row, ect).