DAC8812 with encoder

#include "SPI.h"

// Pin 10 = CS
// Pin 11 = Serial data out
// Pin 13 = CLK
// Pin 8 = DACResetPin

const int slaveSelectPin = 10;
const int DACResetPin = 8;
int timedelay = 500;
double dbLevel = -30;
double dbIncrement = 0.5;
unsigned int dac_level;
// Address code 3 = Both A and B DACs
int addr_decode = 3;
// Encoder stuff
const int encoderPowerPin = 4;
const int encoderGroundPin = 5;
int encoder0PinA = 6;
int encoder0PinB = 7;
int encoder0Pos = 0;
int encoder0PinALast = LOW;
int n = LOW;

void setup() {
  // set the slaveSelectPin as an output:
  pinMode (slaveSelectPin, OUTPUT);
  // Set DAC reset pin high to disable that feature
  pinMode (DACResetPin, OUTPUT);
  digitalWrite(DACResetPin, HIGH);
  // Set up pins for encoder:
  pinMode (encoder0PinA,INPUT);
  pinMode (encoder0PinB,INPUT);
  pinMode (encoderPowerPin, OUTPUT);
  pinMode (encoderGroundPin, OUTPUT);
  digitalWrite(encoderPowerPin,HIGH);
  digitalWrite(encoderGroundPin,LOW);
  // Serial
  Serial.begin (9600);
  // Sleep
  delay(1000);
  Serial.println ("Starting SPI..");
  SPI.begin();
  Serial.println ("Setting volume to 0..");
  DACWrite(addr_decode, 0);
}
//////////////////////////////////////////////////////////////////////////////////////////////
int WriteAndPrintLevel(){
  Serial.print ("dB: ");
  Serial.print (dbLevel);
  Serial.print (" / DAC Level: ");
  Serial.println (dac_level);
  DACWrite(addr_decode, dac_level);
}
int VolumeUp() {
  if (dbLevel < (0-dbIncrement)) {
    dbLevel = dbLevel + dbIncrement;
    dac_level = 65536*(pow(10, (dbLevel/20)));
    WriteAndPrintLevel();
  }
}
int VolumeDown() {
  if (dbLevel > -102.5) {
    dbLevel = dbLevel - dbIncrement;
    dac_level = 65536*(pow(10, (dbLevel/20)));
    WriteAndPrintLevel();
  }
}


///////////////////////////////
// Main loop
////////////////////////////////
void loop() {
  n = digitalRead(encoder0PinA);
  if ((encoder0PinALast == LOW) && (n == HIGH)) {
    if (digitalRead(encoder0PinB) == LOW) {
      VolumeUp();
    } else {
      VolumeDown();
    }
  }
  encoder0PinALast = n;
}

///////////////////////////////
// Function to set DAC level
////////////////////////////////
void DACWrite(int addr_decode, unsigned int level) {
  digitalWrite(slaveSelectPin,LOW);
  SPI.transfer(addr_decode);
  byte highByte = level >> 8;
  unsigned int lowBytetemp = level << 8;
  byte lowByte = lowBytetemp >> 8;
  SPI.transfer(highByte);
  SPI.transfer(lowByte);
  digitalWrite(slaveSelectPin,HIGH);
}