Programming Lego Mindstorms NXT

Chapter 4. Loops

Introduction

A loop repeats a whole program or part of a program. Once the microcontrollers have entered a loop, they read the instructions in the loop over and over again, repeating the actions programmed within the loop. They exit at the end of the loop only when a given condition applies. We find the same sort of thing in a musical score (Figure 4.1).

Figure 4.1. This musical score is an example of a loop that is repeated once. The two pairs of dots on the right tell the musician to go back and play part of the score again. By contrast, a loop block usually repeats more than once, perhaps many times or even “forever.”