MFRC522 Library didn't work, black Serial Monitor.

I’m using RC522 module on Arduino UNO, and the code is using MFRC522 Library from Manage Library Arduino IDE.

it works for the compile and upload. But after done uploading, the serial monitor show nothing.I’ve recheck the wiring and there is nothing wrong with it, i wire it as the code note.

Please inform me if you know how to solve my problem, Thankyou.

Try uploading this sketch to your Uno:

void setup() {
  Serial.begin(9600);
}

void loop() {
  Serial.println("hello");
  delay(1000);
}

Then open the Serial Monitor, do you see "hello" being printed over and over every second?

pert:
Try uploading this sketch to your Uno:

void setup() {

Serial.begin(9600);
}

void loop() {
  Serial.println("hello");
  delay(1000);
}



Then open the Serial Monitor, do you see "hello" being printed over and over every second?

Yes it is, "hello" printed every second.

If i change the MFRC522 library with "https://github.com/miguelbalboa/rfid"

the serial monitor print like this

Firmware Version: 0xFF = (unknown)
WARNING: Communication failure, is the MFRC522 properly connected?
Scan PICC to see UID, SAK, type, and data blocks...

and it won't detect anything

did you look up the example here? Arduino Playground - MFRC522