#include <SPI.h>

const int CS_PIN = 10;

void setup() {
  Serial.begin(115200);

  pinMode(CS_PIN, OUTPUT);
  digitalWrite(CS_PIN, HIGH);  // CS auf High, wenn nicht aktiv

  SPI.begin(6, 2, 7); // SCK, MISO, MOSI
  SPI.beginTransaction(SPISettings(1000000, MSBFIRST, SPI_MODE0)); // Max. 1 MHz wie empfohlen

  //Soft-Reset
  writeRegister(0x2A, 0b00000010);
  uint16_t softReset = readRegister(0x26);
  Serial.print("Soft-Reset: ");
  Serial.println(softReset);
  //Modus-Wahl
  writeRegister(0x26, 0b00000000); //Standby-Mode
  uint16_t mode1 = readRegister(0x26);
  Serial.print("Mode_1: ");
  Serial.println(mode1);
  writeRegister(0x27, 0b11100000); //0x27 = DIGITAL ENABLE Reg  /  -> x-, y-, z-Achse und Temperatur aktivieren =  1111, FIFO = 0, Double Speed = 0, INT01_EVENT = 0, PARITY_EN = 
  uint16_t dig_En = readRegister(0x27);
  Serial.print("Dig_En: ");
  Serial.println(dig_En);
  writeRegister(0x26, 0b00001100); //0x26 = OP_Mode-Reg. /  -> 4G == 00 , PDM = 0, Audio = 0, High Performance Mode = 1100
  uint16_t mode2 = readRegister(0x26);
  Serial.print("Mode_2: ");
  Serial.println(mode2);

  
  //Status
  uint16_t status0 = readRegister(0x11);
  uint16_t status1 = readRegister(0x12);
  uint16_t status2 = readRegister(0x13);
  uint16_t status3 = readRegister(0x14);

  //Status
  Serial.print("Status0: ");
  Serial.println(status0);
  Serial.print("Status1: ");
  Serial.println(status1);
  Serial.print("Status2: ");
  Serial.println(status2);
  Serial.print("Status3: ");
  Serial.println(status3);

  
}

void loop() {

  //x-Achse lesen
  uint16_t ID = readRegister(0x00);
  uint16_t xH_Data = readRegister(0x15);
  uint16_t xL_Data = readRegister(0x16);
  uint16_t h_Temp = readRegister(0x1B);
  uint16_t l_Temp = readRegister(0x1C);
  //uint16_t xH_Data1 = readRegister1(0x15);
  //uint16_t xL_Data1 = readRegister1(0x16);
  int x_Achse = axis(xL_Data, xH_Data);

  //Device ID ausgeben
  test_ID();

  //Ausgabe
  Serial.print("ID: ");
  Serial.println(ID,HEX);
  Serial.print("X-Achse: ");
  Serial.println(x_Achse, HEX);

  //Ausgabe mit einfachem transfer
  Serial.print("xL_Data: ");
  Serial.println(xL_Data);
  Serial.print("xH_Data: ");
  Serial.println(xH_Data);
  /*
  Serial.print("H_Temperatur: ");
  Serial.println(h_Temp);
  Serial.print("L_Temperatur: ");
  Serial.println(l_Temp);
  */
  /*
  //Ausgabe mit zusätzlichem transfer
  Serial.print("xL_Data1: ");
  Serial.println(xL_Data1);
  Serial.print("xH_Data1: ");
  Serial.println(xH_Data1);
  */

  delay(400);
}

//Register schreiben
void writeRegister(uint8_t registerAddress, uint8_t value) {
  uint16_t command = ((registerAddress << 9) | value); // R/W-Bit = 0

  digitalWrite(CS_PIN, LOW);
  
  SPI.transfer16(command);

  digitalWrite(CS_PIN, HIGH);
}

///////////////////////////////////////////////////////////////////////////////////
//Register lesen
uint16_t readRegister(uint8_t registerAddress){
    
    digitalWrite(CS_PIN, LOW);

    uint16_t data = SPI.transfer16((registerAddress<<9) | (0x01<<8));

    digitalWrite(CS_PIN, HIGH);

    return data;
}

/*
uint16_t readRegister1(uint8_t registerAddress){
    
    digitalWrite(CS_PIN, LOW);

    SPI.transfer16((registerAddress<<9) | (0x01<<8));

    uint16_t result = SPI.transfer16(0x0000);
    digitalWrite(CS_PIN, HIGH);

    return result;
}
*/
///////////////////////////////////////////////////////////////////////////////////

//Oberes und unteres Byte der Achsen zusammenführen
int axis (uint16_t data_L, uint16_t data_H){
  int data =0;
  data_L = data_L & 0b0000000011111111;
  data_H = data_H & 0b0000000011111111;
  data = (data_H<<8) | data_L;
  return data;
}


//Als Referenz, ob die Verbindung zum ADXL380 noch besteht
void test_ID(){

  digitalWrite(CS_PIN, LOW);

  uint8_t highByte = SPI.transfer((0x00<<1) | 0x01); // MSB
  uint8_t lowByte  = SPI.transfer(0x00); // LSB

  digitalWrite(CS_PIN, HIGH);

  // Ausgabe der Device ID
  Serial.print("Device ID: 0x");
  Serial.println(lowByte, HEX); // nur das zweite Byte enthält Daten
}