#include <TinyWireM.h>                  // I2C Master lib for ATTinys which use USI
#include <SendOnlySoftwareSerial.h>


//SoftwareSerial mySerial(0, 1); // RX, TX
SendOnlySoftwareSerial mySerial(1); // TX

//#define BUFFER_SIZE 25


#define ADXL343_ADDRESS                 (0x53)    // I2C ADXL343 ALT Address
//#define ADXL343_REG_DATAX0              (0x32)    // X-axis data 0
//#define ADXL343_REG_DATAY0              (0x34)    // Y-axis data 0
//#define ADXL343_REG_DATAZ0              (0x36)    // Z-axis data 0


uint8_t adxl343WriteRegister(uint8_t reg, uint8_t value) {
  TinyWireM.beginTransmission(ADXL343_ADDRESS);
  TinyWireM.write((uint8_t)reg);
  TinyWireM.write((uint8_t)value);
  TinyWireM.endTransmission();
}

uint8_t adxl343ReadRegister(uint8_t reg) {
  TinyWireM.beginTransmission(ADXL343_ADDRESS);
  TinyWireM.write((uint8_t)reg);
  TinyWireM.endTransmission();
  TinyWireM.requestFrom(ADXL343_ADDRESS, 1);
  return TinyWireM.read();
}

int16_t adxl343ReadWord(uint8_t reg) {
  TinyWireM.beginTransmission(ADXL343_ADDRESS);
  TinyWireM.write((uint8_t)reg);
  TinyWireM.endTransmission();
  TinyWireM.requestFrom(ADXL343_ADDRESS, 2);
  return (uint16_t)(TinyWireM.read() | (TinyWireM.read() << 8));
}


void setup() {
  delay(2000);
  mySerial.begin(9600);
  mySerial.flush();
  mySerial.print("hello_serial: starting\n");

  TinyWireM.begin();
  delay(2000);
  uint8_t deviceId = adxl343ReadRegister(0x00);
  mySerial.print(" deviceId: ");
  mySerial.println(deviceId);
  
  adxl343WriteRegister(0x2D,0x08); // POWER_CTL register
//  adxl343WriteRegister(0x31,0x08); // Full res register
  delay(2000);
}

void loop() {
  _delay_ms(200);

  int16_t x = adxl343ReadWord(0x32);//ADXL343_REG_DATAX0);
  int16_t y = adxl343ReadWord(0x34);//ADXL343_REG_DATAY0);
  int16_t z = adxl343ReadWord(0x36);////ADXL343_REG_DATAZ0);

 mySerial.print("x: ");
  mySerial.print(x);
  mySerial.print("\ty: ");
  mySerial.print(y);
  mySerial.print("\tz: ");
  mySerial.println(z);
}