Good day, I have this problem with my simple project. I have a database with all RFID number of employee. What I want to do is to use an rfID to check if it is registered in the database. If it is, it would return a value of 1 else would be a value of 0.

I tried with arduino HanRun Ethernet shield. I was able to get a response from the php web server to the serial monitor. Tried the seeedrfid it successfully get the rfcard number. However, when i tried to combine the two, it would hang on Ethernet.begin(mac, ip) initialization. My code is below.

#include <Ethernet.h>
#include <SoftwareSerial.h>
#include <SeeedRFID.h>

#define RFID_RX_PIN 10
#define RFID_TX_PIN 11


char state = '0';
char c;
byte mac[] = {0x60, 0xF8, 0x1D, 0xBA, 0x1D, 0x52};
IPAddress ip(192, 168, 20, 228);

EthernetClient client;

void setup() {
  // put your setup code here, to run once:
  Serial.println("Serial set up");

  Ethernet.begin(mac, ip);
  Serial.print("My IP Address: ");

void loop() {

  long rfID;
  // put your main code here, to run repeatedly:

  if (RFID.isAvailable()) {
    rfID = RFID.cardNumber();

Serial.println(rfID) is not executed unless I remove the Ethernet.begin(mac, ip). Can anybody point me to the right direction?

  • It's NOT a HanRun Ethernet Shield! It's an unbranded Ethernet Shield happens to use a HanRun HR911105A RJ45 Socket with Integrated Magnetics on it. kosmodrom.com.ua/pdf/HR911105A.pdf
    – Majenko
    Aug 23 '17 at 10:02
  • What pins did you connect the RFIC board to?
    – Avamander
    Aug 25 '17 at 15:02

The Arduino Ethernet shield uses pins 4, 10,11,12,13. You have a conflict with the RFID pins.

  • SPI pins can overlap, SS should be independent. There's not too much info about the chipset used though.
    – Avamander
    Aug 25 '17 at 15:01
  • can they overlap with software serial RX/TX?
    – Juraj
    Aug 26 '17 at 5:08
  • 1
    SPI can't overlap with softserial.
    – Avamander
    Aug 26 '17 at 11:28

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.