Arduino Due Fast ADC script

Fast ADC CH6 CH7

unsigned long start_time;
unsigned long stop_time;
unsigned long values[2000];

void setup() {        
  Serial.begin(115200);  
  REG_ADC_MR = 0x10380180;                       // change from 10380200 to 10380180, 1 is the PREESCALER and 8 means FREERUN
  ADC -> ADC_CHER = 0x03;                        // enable ADC on pin A0
}

void loop() {
  unsigned int i;
  //reads in on pins 6 and 7
    
  start_time = micros();
  for(i=0;i<1000;i++){
    while((ADC->ADC_ISR & 0x03)==0); // wait for conversion
    values[i]=ADC->ADC_CDR[0];
    values[i+1000]=ADC->ADC_CDR[1];//get values
  }
  stop_time = micros();

  Serial.print("Total time: ");
  Serial.println(stop_time-start_time); 
  Serial.print("Average time per conversion: ");
  Serial.println((float)(stop_time-start_time)/2000);

  Serial.println("Values: ");
  for(i=0;i<1000;i++) {
    Serial.print(values[i]);
    Serial.print(", ");
    Serial.println(values[i+1000]);
  }
  
  delay(2000);
}