Program 3. Snake

This example uses the Slider to make a wiggly snake animation when you move the slider. This is a little difficult to describe, so perhaps just try it out: https://makecode.microbit.org/_hgvDyoM2KVEP

The code uses an array to keep track of the dot position on each row. The forever block first shuffles all the dot positions up one place using a for loop. It then clears the display and then sets the position of the bottom most dot to be determined by the slider position. It then draws all the dots. The pause block just slow things down. Here is the MicroPython code which follows exactly the same pattern. You will find it in the file slider_snake.py from microbit import * import time

positions = [2, 2, 2, 2, 2]

def scroll_up(): for y in range(4): positions[y] = positions[y + 1]

while True: display.clear() scroll_up() positions[4] = int(pin2.read_analog() / 240) for y2 in range(5): display.set_pixel(positions[y2], y2, 9) time.sleep(0.1)

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