Turn On and Off an LED with a Light Sensor

Code

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/* 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 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) 2021 Let's Start Coding. License: www.letsstartcoding.com/bsdlicense
 

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Quiz

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




2. Which syntax ends a single code command?