const int POT0_SHUTDOWN = 0x21;

const int POT1_SHUTDOWN = 0x22;

const int BOTH_POT_SHUTDOWN = 0x23;

/***********************Customized Varialbes**********************/

//resistance value byte (0 - 255)

//The wiper is reset to the mid-scale position upon power-up, i.e. POT0_Dn =

POT1_Dn = 128

int POT0_Dn = 128;

int POT1_Dn = 128;

int BOTH_POT_Dn = 128;

//Function Declaration

void DigitalPotTransfer(int cmd, int value);

//send the command and the w

iper value through SPI

void setup()

{

Serial.begin(115200);

pinMode(CS_PIN, OUTPUT);

// set the CS_PIN as an output:

SPI.begin();

// initialize SPI:

}

void loop()

{

// change the resistance on the POT0 from min to max:

for (int POT_Dn = 0; POT_Dn < 256; POT_Dn++) {

DigitalPotWrite(POT0_SEL, POT_Dn);

delay(1);

}

// change the resistance on the POT0 from max to min:

for (int POT_Dn = 0; POT_Dn < 256; POT_Dn++) {

DigitalPotWrite(POT0_SEL , 255 - POT_Dn);

delay(1);