Arduino ethernet Shield + NFC Shield V2.0b Don´t Work

Hi I’m new in aurduino;

My problem is that I bought an Arduino Ethernet Shield and NFC Shield V2.0b, I downloaded the PN532 library from http://www.seeedstudio.com/wiki/NFC_Shield_V2.0 And when I try the example readMifare the Serial monitor prints “Didn’t find PN53x board” the code is:

#include <PN532.h>
#include <SPI.h>

/*Chip select pin can be connected to D10 or D9 which is hareware optional*/
/*if you the version of NFC Shield from SeeedStudio is v2.0.*/
#define PN532_CS 10
PN532 nfc(PN532_CS);
#define  NFC_DEMO_DEBUG 1

void setup(void) {
#ifdef NFC_DEMO_DEBUG
  Serial.begin(9600);
  Serial.println("Hello!");
#endif
  nfc.begin();

  uint32_t versiondata = nfc.getFirmwareVersion();
  if (! versiondata) {
#ifdef NFC_DEMO_DEBUG
    Serial.print("Didn't find PN53x board");
#endif
    while (1); // halt
  }
#ifdef NFC_DEMO_DEBUG
  // Got ok data, print it out!
  Serial.print("Found chip PN5"); 
  Serial.println((versiondata>>24) & 0xFF, HEX);
  Serial.print("Firmware ver. "); 
  Serial.print((versiondata>>16) & 0xFF, DEC);
  Serial.print('.'); 
  Serial.println((versiondata>>8) & 0xFF, DEC);
  Serial.print("Supports "); 
  Serial.println(versiondata & 0xFF, HEX);
#endif
  // configure board to read RFID tags and cards
  nfc.SAMConfig();
}


void loop(void) {
  uint32_t id;
  // look for MiFare type cards
  id = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A);

  if (id != 0) {
#ifdef NFC_DEMO_DEBUG
    Serial.print("Read card #"); 
    Serial.println(id);
#endif
  }
}

What actually happens when you right shift smiley face times? There REALLY is a reason that we expect you to post code in code tags. Read the sticky at the top of the forum that you were SUPPOSED to read FIRST.

#define PN532_CS 10

Pin 10 is the Ethernet shield chip select pin. It can NOT be used as the NFC shield chip select pin.

You may not be able to just arbitrarily select a chip select pin. You need to look at the schematic for the board, and see if there is anything that forces pin 10 to be the chip select pin. It may be that you simply can't use the NFC shield with the Ethernet shield.