Pasted

/*
VCC 3.3V
SWIM    Unconnected
GND GND
NRST    Unconnected
VCC 3.3V
TXD GPIO 16 (or any other available GPIO, except 6-11 and 34-39)
RXD GPIO 17 (or any other available GPIO, except 6-11 and 34-39)
GND GND
*/
 
#include <HardwareSerial.h>
 
// Define the HardwareSerial pins (RX, TX)
HardwareSerial RFID_Serial(1); // Use UART1
const int RXD_PIN = 16;
const int TXD_PIN = 17;
 
void setup() {
  // Configure the pins for UART1
  RFID_Serial.begin(9600, SERIAL_8N1, RXD_PIN, TXD_PIN);
 
  // Open serial communications for debugging and set the baud rate:
  Serial.begin(115200);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }
}
 
void loop() {
  if (RFID_Serial.available()) {
    Serial.write(RFID_Serial.read());
  }
  if (Serial.available()) {
    RFID_Serial.write(Serial.read());
  }
}