#include <Wire.h>

// ADXL345 I2C address is 0x53(83)
#define ADXL345_ADDR 0x53

void setup() {
  // Initialize I2C communication
  Wire.begin();
  
  // Initialize Serial communication
  Serial.begin(115200);

  // Start I2C transmission to set up ADXL345
  Wire.beginTransmission(ADXL345_ADDR);
  // Access register 0x2D (Power control)
  Wire.write(0x2D);
  // Set measure bit (0x08)
  Wire.write(0x08);
  // Stop I2C transmission
  Wire.endTransmission();
  
  delay(10);
}

void loop() {
  // Start I2C transmission to read data from ADXL345
  Wire.beginTransmission(ADXL345_ADDR);
  // Select register 0x32 (Data start)
  Wire.write(0x32);
  // Stop I2C transmission
  Wire.endTransmission();

  // Request 6 bytes of data from ADXL345
  Wire.requestFrom(ADXL345_ADDR, 6);

  // Read 6 bytes of data (x, y, and z acceleration)
  int x = Wire.read() | (Wire.read() << 8);
  int y = Wire.read() | (Wire.read() << 8);
  int z = Wire.read() | (Wire.read() << 8);

  // Convert to g-force (assuming ±16g range and 10-bit data)
  float x_g = x * 0.0039; // 0.0039 g/LSB for ±16g
  float y_g = y * 0.0039;
  float z_g = z * 0.0039;

  // Create JSON string manually
  String jsonString = "{";
  jsonString += "\"time\": " + String(millis()) + ", ";
  jsonString += "\"x\": " + String(x_g, 4) + ", ";
  jsonString += "\"y\": " + String(y_g, 4) + ", ";
  jsonString += "\"z\": " + String(z_g, 4);
  jsonString += "}";

  // Send JSON string over Serial
  Serial.println(jsonString);

  delay(100);
}