Hi all. I am working with an ESP32s with a common anode RGB LED. I am trying to get different colors by varying the colors using PWM. I've looked at different examples, but I can't get this to work.
I am using the following circuit:
I am using the RGB LED example ledCWrite_RGB01 which I include here for completeness. Any orientation is welcomed and appreciated. Thank you!
/*
ledcWrite_RGB.ino
Runs through the full 255 color spectrum for an rgb led
Demonstrate ledcWrite functionality for driving leds with PWM on ESP32
This example code is in the public domain.
Some basic modifications were made by vseven, mostly commenting.
*/
// Set up the rgb led names
uint8_t ledR = A4;
uint8_t ledG = A5;
uint8_t ledB = A18;
uint8_t ledArray[3] = {1, 2, 3}; // three led channels
const boolean invert = true; // set true if common anode, false if common cathode
uint8_t color = 0; // a value from 0 to 255 representing the hue
uint32_t R, G, B; // the Red Green and Blue color components
uint8_t brightness = 255; // 255 is maximum brightness, but can be changed. Might need 256 for common anode to fully turn off.
// the setup routine runs once when you press reset:
void setup()
{
Serial.begin(115200);
delay(10);
ledcAttachPin(ledR, 1); // assign RGB led pins to channels
ledcAttachPin(ledG, 2);
ledcAttachPin(ledB, 3);
// Initialize channels
// channels 0-15, resolution 1-16 bits, freq limits depend on resolution
// ledcSetup(uint8_t channel, uint32_t freq, uint8_t resolution_bits);
ledcSetup(1, 12000, 8); // 12 kHz PWM, 8-bit resolution
ledcSetup(2, 12000, 8);
ledcSetup(3, 12000, 8);
}
// void loop runs over and over again
void loop()
{
Serial.println("Send all LEDs a 255 and wait 2 seconds.");
// If your RGB LED turns off instead of on here you should check if the LED is common anode or cathode.
// If it doesn't fully turn off and is common anode try using 256.
ledcWrite(1, 255);
ledcWrite(2, 255);
ledcWrite(3, 255);
delay(2000);
Serial.println("Send all LEDs a 0 and wait 2 seconds.");
ledcWrite(1, 0);
ledcWrite(2, 0);
ledcWrite(3, 0);
delay(2000);
Serial.println("Starting color fade loop.");
for (color = 0; color < 255; color++) { // Slew through the color spectrum
hueToRGB(color, brightness); // call function to convert hue to RGB
// write the RGB values to the pins
ledcWrite(1, R); // write red component to channel 1, etc.
ledcWrite(2, G);
ledcWrite(3, B);
delay(100); // full cycle of rgb over 256 colors takes 26 seconds
}
}
// Courtesy http://www.instructables.com/id/How-to-Use-an-RGB-LED/?ALLSTEPS
// function to convert a color to its Red, Green, and Blue components.
void hueToRGB(uint8_t hue, uint8_t brightness)
{
uint16_t scaledHue = (hue * 6);
uint8_t segment = scaledHue / 256; // segment 0 to 5 around the
// color wheel
uint16_t segmentOffset =
scaledHue - (segment * 256); // position within the segment
uint8_t complement = 0;
uint16_t prev = (brightness * ( 255 - segmentOffset)) / 256;
uint16_t next = (brightness * segmentOffset) / 256;
if(invert)
{
brightness = 255 - brightness;
complement = 255;
prev = 255 - prev;
next = 255 - next;
}
switch(segment ) {
case 0: // red
R = brightness;
G = next;
B = complement;
break;
case 1: // yellow
R = prev;
G = brightness;
B = complement;
break;
case 2: // green
R = complement;
G = brightness;
B = next;
break;
case 3: // cyan
R = complement;
G = prev;
B = brightness;
break;
case 4: // blue
R = next;
G = complement;
B = brightness;
break;
case 5: // magenta
default:
R = brightness;
G = complement;
B = prev;
break;
}
}