ID12LA example code not working on Arduino Leonardo - arduino

Question

I am trying to get the following code running on an Arduino Leonardo (because it has native usb) and it doesn't work. It doesn't even print anything to the serial monitor. When I try it with an Arduino Nano, everything works fine. I have considered whether maybe it is because the softwareSerial library doesn't work with Leonardo, but I couldn't find any information about it online. Anybody has any idea why it doesn't work?
/*****************************
RFID-powered lockbox
Written by: acavis, 3/31/2015
Modified: Ho YUN "Bobby" Chan # SparkFun Electronics Inc., 11/10/2017
Inspired by & partially adapted from
http://bildr.org/2011/02/rfid-arduino/
Description: This sketch will move a servo when
a trusted tag is read with the
ID-12/ID-20 RFID module
----------HARDWARE HOOKUP----------
PINOUT FOR SERVO MOTOR
Servo Motor ----- Arduino
GND GND
Vcc 5V
SIG D9
PINOUT FOR SPARKFUN RFID USB READER
Arduino ----- RFID module
5V VCC
GND GND
D2 TX
PINOUT FOR SPARKFUN RFID BREAKOUT BOARD
Arduino ----- RFID module
5V VCC
GND GND
GND FORM
D2 D0
Optional: If using the breakout, you can also
put an LED & 330 ohm resistor between
the RFID module's READ pin and GND for
a "card successfully read" indication.
Note: Make sure to GND the FORM pin to enable the ASCII output format.
--------------------------------------------------
******************************/
#include <SoftwareSerial.h>
#include <Servo.h>
// Choose two pins for SoftwareSerial
SoftwareSerial rSerial(2, 3); // RX, TX
// Make a servo object
Servo lockServo;
// Pick a PWM pin to put the servo on
const int servoPin = 9;
// For SparkFun's tags, we will receive 16 bytes on every
// tag read, but throw four away. The 13th space will always
// be 0, since proper strings in Arduino end with 0
// These constants hold the total tag length (tagLen) and
// the length of the part we want to keep (idLen),
// plus the total number of tags we want to check against (kTags)
const int tagLen = 16;
const int idLen = 13;
const int kTags = 4;
// Put your known tags here!
char knownTags[kTags][idLen] = {
"111111111111",
"444444444444",
"555555555555",
"7A005B0FF8D6"
};
// Empty array to hold a freshly scanned tag
char newTag[idLen];
void setup() {
// Starts the hardware and software serial ports
Serial.begin(9600);
rSerial.begin(9600);
// Attaches the servo to the pin
lockServo.attach(servoPin);
// Put servo in locked position
// Note: Value may need to be adjusted
// depending on servo motor
lockServo.write(0);
}
void loop() {
// Counter for the newTag array
int i = 0;
// Variable to hold each byte read from the serial buffer
int readByte;
// Flag so we know when a tag is over
boolean tag = false;
// This makes sure the whole tag is in the serial buffer before
// reading, the Arduino can read faster than the ID module can deliver!
if (rSerial.available() == tagLen) {
tag = true;
}
if (tag == true) {
while (rSerial.available()) {
// Take each byte out of the serial buffer, one at a time
readByte = rSerial.read();
/* This will skip the first byte (2, STX, start of text) and the last three,
ASCII 13, CR/carriage return, ASCII 10, LF/linefeed, and ASCII 3, ETX/end of
text, leaving only the unique part of the tag string. It puts the byte into
the first space in the array, then steps ahead one spot */
if (readByte != 2 && readByte!= 13 && readByte != 10 && readByte != 3) {
newTag[i] = readByte;
i++;
}
// If we see ASCII 3, ETX, the tag is over
if (readByte == 3) {
tag = false;
}
}
}
// don't do anything if the newTag array is full of zeroes
if (strlen(newTag)== 0) {
return;
}
else {
int total = 0;
for (int ct=0; ct < kTags; ct++){
total += checkTag(newTag, knownTags[ct]);
}
// If newTag matched any of the tags
// we checked against, total will be 1
if (total > 0) {
// Put the action of your choice here!
// I'm going to rotate the servo to symbolize unlocking the lockbox
Serial.println("Success!");
lockServo.write(180);
}
else {
// This prints out unknown cards so you can add them to your knownTags as needed
Serial.print("Unknown tag! ");
Serial.print(newTag);
Serial.println();
}
}
// Once newTag has been checked, fill it with zeroes
// to get ready for the next tag read
for (int c=0; c < idLen; c++) {
newTag[c] = 0;
}
}
// This function steps through both newTag and one of the known
// tags. If there is a mismatch anywhere in the tag, it will return 0,
// but if every character in the tag is the same, it returns 1
int checkTag(char nTag[], char oTag[]) {
for (int i = 0; i < idLen; i++) {
if (nTag[i] != oTag[i]) {
return 0;
}
}
return 1;
}
Code is from here: https://learn.sparkfun.com/tutorials/sparkfun-rfid-starter-kit-hookup-guide/all

Answer 1

From: https://docs.arduino.cc/learn/built-in-libraries/software-serial
Not all pins on the Mega and Mega 2560 boards support change
interrupts, so only the following can be used for RX: 10, 11, 12, 13,
14, 15, 50, 51, 52, 53, A8 (62), A9 (63), A10 (64), A11 (65), A12
(66), A13 (67), A14 (68), A15 (69). Not all pins on the Leonardo and
Micro boards support change interrupts, so only the following can be
used for RX: 8, 9, 10, 11, 14 (MISO), 15 (SCK), 16 (MOSI).
So this SoftwareSerial rSerial(2, 3); // RX, TX won't work.
Also Arduino Leonardo has two hardware serials. I don't see why you would use SoftwareSerial here.