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Topic: Unable to compile (Read 1 time) previous topic - next topic


Maybe a stupid error but i'm not able to compile this code, it always tell me that the KeyCode was not declare in the scope.
Here the code:

Code: [Select]
// RFID reader for Arduino
// Wiring version by BARRAGAN <http://people.interaction-ivrea.it/h.barragan>
// Modified for Arudino by djmatic
// Re-Modified for Arduino and 125Khz JsxzLz RFID Kit from Ebay by Biohazard

// RFID reader comes with 11 pins: D3 D2 D1 Rest Mcst Gnd L1 L2 PC TX VCC
// We need these to be connected:
// Rest to Arduino pin 2
// Gnd to Arduino GND
// L1 and L2 to the antenna
// TX to Arduino RX0
// VCC To Arduino 5V

int  val = 0;
char code[14];
String keyCode;

String  master = "4B00108513470F";

// 10 digits card code
// 2 digits parity bits

int bytesread = 0;

void setup() {

  Serial.begin(9600);     // RFID reader TX pin, Baud rate: 9600, Data bits: 8, stop bit: 1.
  pinMode(2,OUTPUT);      // Set digital pin 2 as OUTPUT to connect it to the RFID RESET pin
  digitalWrite(2, HIGH);  // Activate the RFID reader
  Serial.println("rfid ready to read");

void loop() {
  if(Serial.available() > 0) {            // if data available from reader
    if((val = Serial.read()) == 10) {     // check for header
      bytesread = 0;
      while(bytesread < 14) {             // read 14 digit code
        if( Serial.available() > 0) {
          val = Serial.read();
          if((val == 10)||(val == 13)) {  // if header or stop bytes before the 10 digit reading
            break;                        // stop reading
          code[bytesread] = val;          // add the digit           
          bytesread++;                    // ready to read next digit 
      if(bytesread == 14) {         // if 14 digit read is complete
        keyCode = code;
        keyCode = keyCode.substring(0,14);
        if (KeyCode == master)
          Serial.println("Master key passed");
      bytesread = 0;
      digitalWrite(2, LOW);               // deactivate the RFID reader for a moment so it will not flood
      delay(1500);                        // wait for a bit
      digitalWrite(2, HIGH);              // Activate the RFID reader

I declare the KeyCode at the statup so why this error


Code: [Select]
keyCode = code;
        keyCode = keyCode.substring(0,14);
        if (KeyCode == master)

keyCode is not the same as KeyCode
Case matters.


I'm probably slow today, sorry, i don't understand what you means?


KeyCode  and keyCode they are NOT the same. This type of programing is case sensitive.
My GitHub:


In this line:-
Code: [Select]
if (KeyCode == master)
it is the first time the compiler has seen the variable KeyCode.
Previously it has only been told about the variable keyCode  which is a different variable.
The first starts with a capital letter and the second a lower case letter. This means they are different variables.


Sorry for the stupid error thanks very much. For sure now it work

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