Question about "uint32_t"

Projects Programming
3

You have the library :wink: Look at what the specific method does.

From Adafruit_NeoPixel/Adafruit_NeoPixel.cpp at master · adafruit/Adafruit_NeoPixel · GitHub

// Convert separate R,G,B into packed 32-bit RGB color.
// Packed format is always RGB, regardless of LED strand color order.
uint32_t Adafruit_NeoPixel::Color(uint8_t r, uint8_t g, uint8_t b) {
  return ((uint32_t)r << 16) | ((uint32_t)g <<  8) | b;
}

// Convert separate R,G,B,W into packed 32-bit WRGB color.
// Packed format is always WRGB, regardless of LED strand color order.
uint32_t Adafruit_NeoPixel::Color(uint8_t r, uint8_t g, uint8_t b, uint8_t w) {
  return ((uint32_t)w << 24) | ((uint32_t)r << 16) | ((uint32_t)g <<  8) | b;
}

It simply places the value of each color in a specific byte in the variable.

// Edit: code snippet that demonstrates

  char txBuffer[32];
  uint32_t red = flora.Color(0,  255,  0);
  sprintf(txBuffer, "0x%08lX (%lu)", red, red);
  Serial.print(txBuffer);

The output will be

0x0000FF00 (65280)

The first number is the hexadecimal representation so you can see what is placed where, the second number (between brackets) the decimal representation.
If you use uint32_t red = flora.Color(0x33,  0xFF,  0x44);, it might be clearer; output:

0x0033FF44 (3407684)

Note: the name red is wrong, should be green :wink: