/*



  CS >>> D10
  SCLK >> D13
  DI  >>> D11
  PA0  VCC
  PBO  GND
  PW0  >>> led.
  */
#include <SPI.h>
int TensionLue = 1;
int TensionBrute = 0;
float Voltage = 0;
const int CS= 10;

void setup()
{
  pinMode (CS, OUTPUT);
  Serial.begin(9600);
  SPI.begin();

}

void loop()
{
    for (int i = 0; i <= 255; i++)
    {
      digitalPotWrite(i);
      delay(10);
      TensionBrute = analogRead( TensionLue);
      Voltage = (TensionBrute * 5.0 )/ 1024.0;
      //Serial.print("Level = " );
      //Serial.print(i);
      Serial.print("\t Voltage = ");
      Serial.println(Voltage,3);
    }
    delay(500);
    for (int i = 255; i >= 0; i--)
    {
      digitalPotWrite(i);
      delay(10);
      TensionBrute = analogRead( TensionLue);
      Voltage = (TensionBrute * 5.0 )/ 1024.0;
      //Serial.print("Level = " );
      //Serial.print(i);
      Serial.print("\t Voltage = ");
      Serial.println(Voltage,3);
    }
}

int digitalPotWrite(int value)
{
  digitalWrite(CS, LOW);
  SPI.transfer(B00010001);
  SPI.transfer(value);
  digitalWrite(CS, HIGH);
}