PIR to SAMD21 to WS28212b Fade Color 250730

[gcjr]

@AllenPitts

  for( int colorStep=0; colorStep<256; colorStep++ ) {
      int r = colorStep;  // Redness starts at zero and goes up to full
      int b = 255-colorStep;  // Blue starts at full and goes down to zero
      int g = 0;              // No green needed to go from blue to red

      // Now loop though each of the LEDs and set each one to the current color
      for(int x = 0; x < NUM_LEDS; x++)
          leds[x] = CRGB(r,g,b);

      // Display the colors we just set on the actual LEDs
      FastLED.show();
      delay(10); 
  }

presumably you want to do the above in reverse. without any delay between setting each LED, just the color sequence can be reversed. So the above code needs to be duplicated and the color sequence reversed

  for( int colorStep=256; colorStep>0; colorStep--) {