Analog to Digital Converter with Arduino Uno and ads7883

Hello, I made my Analog to Digital Converter few hours ago. However, it doesn't work. It just print 0 all the time. Please give me any suggestion.

I refered the code from here. " Talking to the ADS7883 with the Arduino Uno - Networking, Protocols, and Devices - Arduino Forum " In there, same IC chip and same content.

Here is my code.

#include <SPI.h>

const byte slaveSelectPin = 10; //CS

void setup() {
  Serial.begin(9600);
  pinMode(slaveSelectPin,OUTPUT);
  digitalWrite(slaveSelectPin,HIGH); //chip active LOW
 
  SPI.begin();
  SPI.setBitOrder(MSBFIRST);
  SPI.setDataMode(SPI_MODE1);
  SPI.setClockDivider(SPI_CLOCK_DIV16);
 
  Serial.println("Initialized!");
}

void loop() {
  long readADC = SpiRead();
  Serial.println(readADC);
}

long SpiRead(void) {
  byte result;
  byte b;
 
  digitalWrite(slaveSelectPin,LOW);
  result = SPI.transfer(0xFF);
  result <<= 8;
  b = SPI.transfer(0xFF);
  result |= b;
  result = result>>2; 
 
  digitalWrite(slaveSelectPin,HIGH);
  return(result); 
}

Most probably a wiring problem. As you failed to provide a wiring diagram of your setup we cannot help you further. A link to the used board may also be necessary if you don't use the chip directly.