use of variable globally

i just want tu use an Array and interger variabl all over in my cpp file.
i’d like to use it my serialaevent() function and in other function of the class, so that the Array can be modified whenever the SerialEvent() funtion is called.
below the Header and cpp files.

h file

#ifndef RFID_h
#define RFID_h
#include "Arduino.h"

class RFID{      
friend void serialEvent();

       void Senden(int Nutzbytesanzahl,byte NTZBYTE1, byte NTZBYTE2);            
       byte* Empfangen(int laenger_der_gelesene_bytes);
       int Fehlerbehandlung(int  laenger_der_gelesene_bytes);
       uint8_t Send_Recievepin;
     int counter;
       static byte tel; 
     RFID( uint8_t Send_Recievepin);
     int Get_Sw_Version();
     int Get_Hw_Version();
     int Transmitter_On();
     int Get_System_Infos();
     int Parameter();
     byte* Read_Block();         

cpp file

byte* RFID::Read_Block()
Senden(RB_Nutzbytesanzahl,RB_Nutzbyte1, RB_Nutzbyte2);
digitalWrite(Send_Recievepin, LOW);
if (counter<=1)
return tel;

else if (counter>=11)
return tel;
void serialEvent()
if (Serial.available()>0){

if (tel[counter]==0x77){
   counter ++;
   return tel[counter];
else if (tel[counter]==0xAA){
     counter ++;

thank you in a anticipation

Please edit your code with code tags (as described in the sticky - the one obviously marked "how to use this forum" but which you obviously didn't read).

That red text in your code doesn't look like it belongs there, and there may be more that's modified by the forum code.

Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.,148850.0.html . Then look down to item #7 about how to post your code.
It will be formatted in a scrolling window that makes it easier to read.

Thanks.. Tom... :slight_smile:

sorry; it just done , it was a misunderstanding.
can you help me please :slight_smile:

Do you have a question?

i want to declar my Array (tel) global and my integer variable (count).
then i want to use it in my cpp file. how can i do it?

Is this thread in any way related to this?

(Think carefully before you answer - it could be a trick question)