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| 1 | +/* |
| 2 | + ledcWrite_RGB.ino |
| 3 | + Runs through the full 255 color spectrum for an rgb led |
| 4 | + Demonstrate ledcWrite functionality for driving leds with PWM on ESP32 |
| 5 | + |
| 6 | + This example code is in the public domain. |
| 7 | + |
| 8 | + Some basic modifications were made by vseven, mostly commenting. |
| 9 | + */ |
| 10 | + |
| 11 | +// Set up the rgb led names |
| 12 | +uint8_t ledR = A4; |
| 13 | +uint8_t ledG = A5; |
| 14 | +uint8_t ledB = A18; |
| 15 | + |
| 16 | +uint8_t ledArray[3] = {1, 2, 3}; // three led channels |
| 17 | + |
| 18 | +const boolean invert = true; // set true if common anode, false if common cathode |
| 19 | + |
| 20 | +uint8_t color = 0; // a value from 0 to 255 representing the hue |
| 21 | +uint32_t R, G, B; // the Red Green and Blue color components |
| 22 | +uint8_t brightness = 255; // 255 is maximum brightness, but can be changed. Might need 256 for common anode to fully turn off. |
| 23 | + |
| 24 | +// the setup routine runs once when you press reset: |
| 25 | +void setup() |
| 26 | +{ |
| 27 | + Serial.begin(115200); |
| 28 | + delay(10); |
| 29 | + |
| 30 | + ledcAttachPin(ledR, 1); // assign RGB led pins to channels |
| 31 | + ledcAttachPin(ledG, 2); |
| 32 | + ledcAttachPin(ledB, 3); |
| 33 | + |
| 34 | + // Initialize channels |
| 35 | + // channels 0-15, resolution 1-16 bits, freq limits depend on resolution |
| 36 | + // ledcSetup(uint8_t channel, uint32_t freq, uint8_t resolution_bits); |
| 37 | + ledcSetup(1, 12000, 8); // 12 kHz PWM, 8-bit resolution |
| 38 | + ledcSetup(2, 12000, 8); |
| 39 | + ledcSetup(3, 12000, 8); |
| 40 | +} |
| 41 | + |
| 42 | +// void loop runs over and over again |
| 43 | +void loop() |
| 44 | +{ |
| 45 | + Serial.println("Send all LEDs a 255 and wait 2 seconds."); |
| 46 | + // If your RGB LED turns off instead of on here you should check if the LED is common anode or cathode. |
| 47 | + // If it doesn't fully turn off and is common anode try using 256. |
| 48 | + ledcWrite(1, 255); |
| 49 | + ledcWrite(2, 255); |
| 50 | + ledcWrite(3, 255); |
| 51 | + delay(2000); |
| 52 | + Serial.println("Send all LEDs a 0 and wait 2 seconds."); |
| 53 | + ledcWrite(1, 0); |
| 54 | + ledcWrite(2, 0); |
| 55 | + ledcWrite(3, 0); |
| 56 | + delay(2000); |
| 57 | + |
| 58 | + Serial.println("Starting color fade loop."); |
| 59 | + |
| 60 | + for (color = 0; color < 255; color++) { // Slew through the color spectrum |
| 61 | + |
| 62 | + hueToRGB(color, brightness); // call function to convert hue to RGB |
| 63 | + |
| 64 | + // write the RGB values to the pins |
| 65 | + ledcWrite(1, R); // write red component to channel 1, etc. |
| 66 | + ledcWrite(2, G); |
| 67 | + ledcWrite(3, B); |
| 68 | + |
| 69 | + delay(100); // full cycle of rgb over 256 colors takes 26 seconds |
| 70 | + } |
| 71 | + |
| 72 | +} |
| 73 | + |
| 74 | +// Courtesy http://www.instructables.com/id/How-to-Use-an-RGB-LED/?ALLSTEPS |
| 75 | +// function to convert a color to its Red, Green, and Blue components. |
| 76 | + |
| 77 | +void hueToRGB(uint8_t hue, uint8_t brightness) |
| 78 | +{ |
| 79 | + uint16_t scaledHue = (hue * 6); |
| 80 | + uint8_t segment = scaledHue / 256; // segment 0 to 5 around the |
| 81 | + // color wheel |
| 82 | + uint16_t segmentOffset = |
| 83 | + scaledHue - (segment * 256); // position within the segment |
| 84 | + |
| 85 | + uint8_t complement = 0; |
| 86 | + uint16_t prev = (brightness * ( 255 - segmentOffset)) / 256; |
| 87 | + uint16_t next = (brightness * segmentOffset) / 256; |
| 88 | + |
| 89 | + if(invert) |
| 90 | + { |
| 91 | + brightness = 255 - brightness; |
| 92 | + complement = 255; |
| 93 | + prev = 255 - prev; |
| 94 | + next = 255 - next; |
| 95 | + } |
| 96 | + |
| 97 | + switch(segment ) { |
| 98 | + case 0: // red |
| 99 | + R = brightness; |
| 100 | + G = next; |
| 101 | + B = complement; |
| 102 | + break; |
| 103 | + case 1: // yellow |
| 104 | + R = prev; |
| 105 | + G = brightness; |
| 106 | + B = complement; |
| 107 | + break; |
| 108 | + case 2: // green |
| 109 | + R = complement; |
| 110 | + G = brightness; |
| 111 | + B = next; |
| 112 | + break; |
| 113 | + case 3: // cyan |
| 114 | + R = complement; |
| 115 | + G = prev; |
| 116 | + B = brightness; |
| 117 | + break; |
| 118 | + case 4: // blue |
| 119 | + R = next; |
| 120 | + G = complement; |
| 121 | + B = brightness; |
| 122 | + break; |
| 123 | + case 5: // magenta |
| 124 | + default: |
| 125 | + R = brightness; |
| 126 | + G = complement; |
| 127 | + B = prev; |
| 128 | + break; |
| 129 | + } |
| 130 | +} |
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