How it works

The raspberry takes a picture each hour (I can remotely launch command using voice) and then filters the pic (labels: Purple, Magenta, Violet, Graphic design). The difference between the two determines the light exposition, increasing or decreasing. The sensor switches blue or red

It communicates through Openweathermap to display on the micro:bit the current forecast (Clouds)

The distant micro:bit counter is set to -1 when it switches to red (the speaker plays a sound) and +2 when it swithes to blue (+8)