For now, I use LDR to control the buzzer output. I put them in an umbrella. Once the value of LDR is greater than 50, the buzzer starts to sing “Mia and Sebastian’s Theme” (Lala Land) and it stops singing when I fold it as well as getting darker. I think it might be quite romantic in rainy day. The problem in the first coding I wrote was that I put too many delay(); there. Instead, I should use millis(); Another thing is that it cannot stop immediately when I put it in dark while buzzer is singing. It means that sensor stops sense the value once if() statement starts and it starts to sense again when all the tone() and delay() in this loop are finished. So I asked a resident YG, he told me that I should add if() statement before each tone() so it can sense for whole time. Another second year student told me millis() is able to solve it. But I am still confused about how to use millis() after watching tutorials on Youtube.

At the first step, I wrote down the numbered musical notations of this song “Mia and Sebastian’s Theme” and then tested tone frequency, finding the right pitch. Then test duration for right rhythm. I was aware of that I should strongly pay attention to using the right resistor in the process. And Serial.println() is a good way to debug. I fixed board to umbrella with tape and connected board with 5v power bank.