| /* | |
| LED bar graph | |
| Turns on a series of LEDs based on the value of an analog sensor. | |
| This is a simple way to make a bar graph display. Though this graph uses 10 | |
| LEDs, you can use any number by changing the LED count and the pins in the | |
| array. | |
| This method can be used to control any series of digital outputs that depends | |
| on an analog input. | |
| The circuit: | |
| - LEDs from pins 2 through 11 to ground | |
| created 4 Sep 2010 | |
| by Tom Igoe | |
| This example code is in the public domain. | |
| https://www.arduino.cc/en/Tutorial/BuiltInExamples/BarGraph | |
| */ | |
| // these constants won't change: | |
| const int analogPin = A0; // the pin that the potentiometer is attached to | |
| const int ledCount = 10; // the number of LEDs in the bar graph | |
| int ledPins[] = { | |
| 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 | |
| }; // an array of pin numbers to which LEDs are attached | |
| void setup() { | |
| // loop over the pin array and set them all to output: | |
| for (int thisLed = 0; thisLed < ledCount; thisLed++) { | |
| pinMode(ledPins[thisLed], OUTPUT); | |
| } | |
| } | |
| void loop() { | |
| // read the potentiometer: | |
| int sensorReading = analogRead(analogPin); | |
| // map the result to a range from 0 to the number of LEDs: | |
| int ledLevel = map(sensorReading, 0, 1023, 0, ledCount); | |
| // loop over the LED array: | |
| for (int thisLed = 0; thisLed < ledCount; thisLed++) { | |
| // if the array element's index is less than ledLevel, | |
| // turn the pin for this element on: | |
| if (thisLed < ledLevel) { | |
| digitalWrite(ledPins[thisLed], HIGH); | |
| } | |
| // turn off all pins higher than the ledLevel: | |
| else { | |
| digitalWrite(ledPins[thisLed], LOW); | |
| } | |
| } | |
| } | |