#include <Wire.h>

#define TCA62724_ADDR   0x55
#define SDA_PIN         10
#define SCL_PIN         9

void setup() {
    Wire.begin(SDA_PIN, SCL_PIN);
    delay(10);
    
    // Enable the LED driver
    Wire.beginTransmission(TCA62724_ADDR);
    Wire.write(0x84);  // Enable register
    Wire.write(0x03);  // Turn on
    Wire.endTransmission();
    
    // Set Purple: Red=1, Green=0, Blue=1 (lowest brightness)
    Wire.beginTransmission(TCA62724_ADDR);
    Wire.write(0x81);  // Blue register
    Wire.write(1);     // Blue = 1
    Wire.write(0x82);  // Green register
    Wire.write(0);     // Green = 0
    Wire.write(0x83);  // Red register
    Wire.write(1);     // Red = 1
    Wire.endTransmission();
}

void loop() {
    // Nothing - LED stays purple
}