Turn On and Off an LED with a Light Sensor

Use the ‘Parts List’ image along with the component cards in your box to correctly plug in the electronic hardware to your Maker Board. The colorful dots next to the legs of the components match up to the ports where that leg should go on Maker Board’s ports.

Code

The code in the editor below is ready to run! Plug in the electronic components just like the Parts List card above, connect Maker Board to your computer's USB port with the cable, and hit 'Upload Your Code!'. Tinker with the code and change something! If you get stuck, you can hit the 'Restore' button to make the code go back to the working example.


/* Turn on an LED light with a light sensor reading The light sensor has a range of 0-1023, so 512 is the halfway threshold */ void setup(){ pinMode(A2,INPUT); //light sensor in the smaller block of ports with + and - ports on either side pinMode(2,OUTPUT); //LED light } void loop(){ if(digitalRead(A2)==LOW){ //if there is low light on the light sensor... digitalWrite(2,HIGH); //turn on LED 2 } else{ //otherwise if there is high light on the light sensor... digitalWrite(2,LOW); //turn off LED 2 } /*Depending on your room lighting, the LED may be on by default. To see the switch work, shine a light on the light sensor! If the LED is off, cover the light sensor with your hand to turn on the LED. */ } // (c) 2019 Let's Start Coding. License: www.letsstartcoding.com/bsdlicense
 

Walkthrough Video

Watch the video for a line-by-line explanation of how the example program works. Then you'll be ready to make some changes of your own!

Challenges

Can you complete the challenges? Change the code in your code editor above. Upload your code to see the effect when you're finished. Complete a challenge? Check it off the list!

Concepts

These are the new code concepts covered in this example program. To become a great coder, read through these concepts to learn new vocabulary.

Quiz

If you're having trouble, try to run an experimental program or look at the example code to help you find the answer.

1. Which syntax ends the entire 'void loop' function?




2. Which syntax ends a single code command?