For a school project me and my friend wanted to make and Arduino based RFID door lock. We got all the right parts and followed the tutorial step by step. but when we try to verify the code we get this error message:
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::RFID(int, int)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::RFID(int, int)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::writeMFRC522(unsigned char, unsigned char)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::reset()'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::readMFRC522(unsigned char)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::setBitMask(unsigned char, unsigned char)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::clearBitMask(unsigned char, unsigned char)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::antennaOn()'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::init()'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::antennaOff()'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::calculateCRC(unsigned char*, unsigned char, unsigned char*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::MFRC522ToCard(unsigned char, unsigned char*, unsigned char, unsigned char*, unsigned int*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::findCard(unsigned char, unsigned char*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::anticoll(unsigned char*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::auth(unsigned char, unsigned char, unsigned char*, unsigned char*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::read(unsigned char, unsigned char*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::write(unsigned char, unsigned char*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::selectTag(unsigned char*)'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\RFID\RFID.cpp.o (symbol from plugin): In function RFID::RFID(int, int)': (.text+0x0): multiple definition of RFID::halt()'
sketch\RFID.cpp.o (symbol from plugin):(.text+0x0): first defined here
collect2.exe: error: ld returned 1 exit status
exit status 1
Error compiling for board Arduino Uno.
This is the code
//The DIY Life
//Michael Klements
//27 January 2020
#include <SPI.h>
#include <RFID.h>
#include <Servo.h>
RFID rfid(10, 9); //D10:pin of tag reader SDA. D9:pin of tag reader RST
unsigned char status;
unsigned char str[MAX_LEN]; //MAX_LEN is 16: size of the array
String accessGranted [2] = {"310988016", "19612012715"}; //RFID serial numbers to grant access to
int accessGrantedSize = 2; //The number of serial numbers
Servo lockServo; //Servo for locking mechanism
int lockPos = 15; //Locked position limit
int unlockPos = 75; //Unlocked position limit
boolean locked = true;
int redLEDPin = 5;
int greenLEDPin = 6;
void setup()
{
Serial.begin(9600); //Serial monitor is only required to get tag ID numbers and for troubleshooting
SPI.begin(); //Start SPI communication with reader
rfid.init(); //initialization
pinMode(redLEDPin, OUTPUT); //LED startup sequence
pinMode(greenLEDPin, OUTPUT);
digitalWrite(redLEDPin, HIGH);
delay(200);
digitalWrite(greenLEDPin, HIGH);
delay(200);
digitalWrite(redLEDPin, LOW);
delay(200);
digitalWrite(greenLEDPin, LOW);
lockServo.attach(3);
lockServo.write(lockPos); //Move servo into locked position
Serial.println("Place card/tag near reader...");
}
void loop()
{
if (rfid.findCard(PICC_REQIDL, str) == MI_OK) //Wait for a tag to be placed near the reader
{
Serial.println("Card found");
String temp = ""; //Temporary variable to store the read RFID number
if (rfid.anticoll(str) == MI_OK) //Anti-collision detection, read tag serial number
{
Serial.print("The card's ID number is : ");
for (int i = 0; i < 4; i++) //Record and display the tag serial number
{
temp = temp + (0x0F & (str[i] >> 4));
temp = temp + (0x0F & str[i]);
}
Serial.println (temp);
checkAccess (temp); //Check if the identified tag is an allowed to open tag
}
rfid.selectTag(str); //Lock card to prevent a redundant read, removing the line will make the sketch read cards continually
}
rfid.halt();
}
void checkAccess (String temp) //Function to check if an identified tag is registered to allow access
{
boolean granted = false;
for (int i=0; i <= (accessGrantedSize-1); i++) //Runs through all tag ID numbers registered in the array
{
if(accessGranted[i] == temp) //If a tag is found then open/close the lock
{
Serial.println ("Access Granted");
granted = true;
if (locked == true) //If the lock is closed then open it
{
lockServo.write(unlockPos);
locked = false;
}
else if (locked == false) //If the lock is open then close it
{
lockServo.write(lockPos);
locked = true;
}
digitalWrite(greenLEDPin, HIGH); //Green LED sequence
delay(200);
digitalWrite(greenLEDPin, LOW);
delay(200);
digitalWrite(greenLEDPin, HIGH);
delay(200);
digitalWrite(greenLEDPin, LOW);
delay(200);
}
}
if (granted == false) //If the tag is not found
{
Serial.println ("Access Denied");
digitalWrite(redLEDPin, HIGH); //Red LED sequence
delay(200);
digitalWrite(redLEDPin, LOW);
delay(200);
digitalWrite(redLEDPin, HIGH);
delay(200);
digitalWrite(redLEDPin, LOW);
delay(200);
}
}
Tutorial: Arduino Based RFID Door Lock - Make Your Own
How do we fix this?