Claude - FastLED random LEDs

// Claude's code for a set of randomly blinking LEDs using CRGBArray / CRGBSet
// 8 strip Neopixel, first two are excluded from the blinking effect

#include <FastLED.h>

// Define the number of LEDs in your strip
#define NUM_LEDS 8
#define DATA_PIN 6  // Connect your NeoPixel data line to this Arduino pin

// Create an array for the LEDs using CRGBArray
CRGBArray<NUM_LEDS> leds;

// Define timing for random color blinking
#define RANDOM_BLINK_MIN 300    // Minimum time a random LED stays in its state
#define RANDOM_BLINK_MAX 2000   // Maximum time a random LED stays in its state

// Number of random blinking LEDs (LEDs 2-7)
#define NUM_RANDOM_LEDS 6

// Arrays to track timing and state for each random blinking LED
unsigned long previousMillis[NUM_RANDOM_LEDS];
unsigned long intervals[NUM_RANDOM_LEDS];
bool blinkState[NUM_RANDOM_LEDS];
CRGB colors[NUM_RANDOM_LEDS];

void setup() {
  // Initialize the FastLED library with your strip configuration
  FastLED.addLeds<NEOPIXEL, DATA_PIN>(leds, NUM_LEDS);
  FastLED.setBrightness(64);  // Set to about 25% brightness

  // Clear all LEDs to start
  FastLED.clear();
  FastLED.show();

  // Initialize random seed
  randomSeed(analogRead(0));

  // Initialize random blink timings, states, and colors
  for (int i = 0; i < NUM_RANDOM_LEDS; i++) {
    // Stagger the starting times
    previousMillis[i] = millis() - random(0, 1000);

    // Randomize initial states with variation to avoid clusters
    blinkState[i] = (random(10) > 5 + i % 3) ? true : false;

    // Assign random intervals
    intervals[i] = random(RANDOM_BLINK_MIN, RANDOM_BLINK_MAX);

    // Generate a random color for each LED
    colors[i] = CHSV(random8(), random(180, 255), random(200, 255));
  }

  // Turn first two LEDs off
  leds(0, 1) = CRGB::Black;
}

void loop() {
  // Run the random blinking function
  randomBlink();

  // Update the LED strip
  FastLED.show();

  // Small delay to prevent flickering
  delay(10);
}

void randomBlink() {
  // Using CRGBSet to address LEDs 2 through 7 (indexes 2-7)
  CRGBSet randomLeds(leds(2, 7));

  // Get the current time
  unsigned long currentMillis = millis();

  // Check each LED in the random set
  for (int i = 0; i < NUM_RANDOM_LEDS; i++) {
    // Check if it's time to update this LED based on its custom interval
    if (currentMillis - previousMillis[i] >= intervals[i]) {
      previousMillis[i] = currentMillis;

      // Toggle state
      blinkState[i] = !blinkState[i];

      if (blinkState[i]) {
        // Generate a new random color when turning on
        colors[i] = CHSV(random8(), random(180, 255), random(200, 255));
        // Generate a new random interval for on state
        intervals[i] = random(RANDOM_BLINK_MIN, RANDOM_BLINK_MAX);
      } else {
        // Generate a new random interval for off state
        intervals[i] = random(RANDOM_BLINK_MIN + 100, RANDOM_BLINK_MAX - 200);
      }
    }

    // Set LED to either its color or black based on current state
    if (blinkState[i]) {
      randomLeds[i] = colors[i];
    } else {
      randomLeds[i] = CRGB::Black;
    }
  }
}