//  ******************************************** HARDWARE IMPORTANT********************************************************
//  With an Arduino UN0/Nano : uses a resistive divider to reduce the voltage:
//  MOSI (pin 11) to ADF DATA
//  SCK (pin13) to ADF CLK
//  Select (PIN 3) to ADF LE
//
//  Resistive divider 560 Ohm with 1000 Ohm to ground on Arduino pins 11, 13 et 3 to adapt from 5V
//  to 3.3V the digital signals DATA, CLK and LE send by the Arduino.
//
//  Arduino pin 2 (for lock detection) directly connected to ADF4351 card MUXOUT.
//  The ADF card is 5V powered by the ARDUINO
//  ******************************************** HARDWARE IMPORTANT********************************************************


#include <SPI.h>

#define ADF4351_LE 3
#define LOCK 2

uint32_t registers[6] =  {0x4E0358, 0x80087D1, 0x4E42, 0x4B3, 0x8C803C, 0x580005} ; // 3910 MHz with 25MHz ref
double RFout, REFin, PFDRFout, OutputChannelSpacing, FRACF;
unsigned int long RFint,RFintold, INTA, MOD, FRAC;
int modif = 0;
byte OutputDivider;

void WriteRegister32(const uint32_t value)   //Programme un registre 32bits
{
  digitalWrite(ADF4351_LE, LOW);
  for (int i = 3; i >= 0; i--)             // loop round 4 x 8bits
    SPI.transfer((value >> 8 * i) & 0xFF); // offset, byte mask and send via SPI
  digitalWrite(ADF4351_LE, HIGH);
  digitalWrite(ADF4351_LE, LOW);
}

void SetADF4351()  // bung the data into the ADF4351
{ for (int i = 5; i >= 0; i--)
    WriteRegister32(registers[i]);
}

void SerialPrintRegisters()
{   
    for (int i = 0; i <=5; i++)
    {
      Serial.print("Register ");
      Serial.print(i);
      Serial.print(" ");
      Serial.print(registers[i],HEX);
      Serial.print(" ");
    }
  Serial.println();
}

void setup() 
{
  Serial.begin (9600);

  pinMode(LOCK,INPUT);
  pinMode(ADF4351_LE, OUTPUT);          // Setup pins
  digitalWrite(ADF4351_LE, HIGH);
  SPI.begin();                          // Init SPI bus
  SPI.setDataMode(SPI_MODE0);           // CPHA = 0 et Clock positive
  SPI.setBitOrder(MSBFIRST);            // poids forts en tête
}

void loop() 
{
  delay (2000);

  SetADF4351();  // Programme tous les registres de l'ADF4351
  SerialPrintRegisters();
}