Removed unused variable key from examples

Author: le78ld

Diff for: examples/ChangeUID/ChangeUID.ino

@@ -35,19 +35,12 @@ MFRC522 mfrc522(SS_PIN, RST_PIN);   // Create MFRC522 instance
 /* Set your new UID here! */
 #define NEW_UID {0xDE, 0xAD, 0xBE, 0xEF}
 
-MFRC522::MIFARE_Key key;
-
 void setup() {
   Serial.begin(9600);  // Initialize serial communications with the PC
   while (!Serial);     // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)
   SPI.begin();         // Init SPI bus
   mfrc522.PCD_Init();  // Init MFRC522 card
   Serial.println(F("Warning: this example overwrites the UID of your UID changeable card, use with care!"));
-  
-  // Prepare key - all keys are set to FFFFFFFFFFFFh at chip delivery from the factory.
-  for (byte i = 0; i < 6; i++) {
-    key.keyByte[i] = 0xFF;
-  }
 }
 
 // Setting the UID can be as simple as this:

Diff for: examples/FixBrickedUID/FixBrickedUID.ino

@@ -32,19 +32,12 @@
 
 MFRC522 mfrc522(SS_PIN, RST_PIN);   // Create MFRC522 instance
 
-MFRC522::MIFARE_Key key;
-
 void setup() {
   Serial.begin(9600);  // Initialize serial communications with the PC
   while (!Serial);     // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)
   SPI.begin();         // Init SPI bus
   mfrc522.PCD_Init();  // Init MFRC522 card
   Serial.println(F("Warning: this example clears your mifare UID, use with care!"));
-  
-  // Prepare key - all keys are set to FFFFFFFFFFFFh at chip delivery from the factory.
-  for (byte i = 0; i < 6; i++) {
-    key.keyByte[i] = 0xFF;
-  }
 }
 
 void loop() {

Diff for: examples/MinimalInterrupt/MinimalInterrupt.ino

@@ -37,8 +37,6 @@
 
 MFRC522 mfrc522(SS_PIN, RST_PIN);   // Create MFRC522 instance.
 
-MFRC522::MIFARE_Key key;
-
 volatile bool bNewInt = false;
 byte regVal = 0x7F;
 void activateRec(MFRC522 mfrc522);

Diff for: examples/ReadNUID/ReadNUID.ino

@@ -38,8 +38,6 @@
 
 MFRC522 rfid(SS_PIN, RST_PIN); // Instance of the class
 
-MFRC522::MIFARE_Key key; 
-
 // Init array that will store new NUID 
 byte nuidPICC[4];
 
@@ -48,13 +46,7 @@ void setup() {
   SPI.begin(); // Init SPI bus
   rfid.PCD_Init(); // Init MFRC522 
 
-  for (byte i = 0; i < 6; i++) {
-    key.keyByte[i] = 0xFF;
-  }
-
   Serial.println(F("This code scan the MIFARE Classsic NUID."));
-  Serial.print(F("Using the following key:"));
-  printHex(key.keyByte, MFRC522::MF_KEY_SIZE);
 }
 
 void loop() {