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Problem SBUF 8051

Hello everybody.

I'm french, so sorry for my english.

First, thanks for all gentlemens who will help me.

I follow a formation about programmation microcontroleur 8051's family.

First I have studied the microcontroleur himself, after I have made a lot of programs in assembleur with Keil, and no problem.

After I have learn the langage C, and I have made a lot of program on my computer for the computer, and now I try to made the same previous program that I have created in assembleur but in langage C, always with Keil, and I have a problem.

The problem is that the hyperterminal diplay :

"Serial number : 1’˜ž¤ª"

instead of display "Serial number : 111111".

The problem is when the program call the fonction VERIFTI(), the veriable unite is lost!!!!
Why ?????

Do you have an idea?

My microcontroleur is an NXP P89V51RD2BN

Please look at my program:


#include <REG51.H>

void VERIFRI()reentrant;
void VERIFTI()reentrant;

data unsigned char cent;
data unsigned char diz;
data unsigned char unite;


void Led_chenillard()
{



SM0=0;                          //UART en mode 1
SM1=1;                          //UART en mode 1
SM2=0;                          //Gestion multiprocesseur inactive
REN=1;                          //Reception active

TMOD=0x20;                      //Config Timer 1 en mode 2 et mode temporisateur
TH1=255;                        //56000 Bauds
TR1=1;                          //Active le timer 1

TI=1;



SBUF=0x0C;                  //Efface écran
VERIFTI();                      //Vérifie si l'envoie au PC est terminé


SBUF='S';
VERIFTI();

SBUF='e';
VERIFTI();

SBUF='r';
VERIFTI();

SBUF='i';
VERIFTI();

SBUF='a';
VERIFTI();

SBUF='lk';
VERIFTI();

SBUF=' ';
VERIFTI();

SBUF='n';
VERIFTI();

SBUF='u';
VERIFTI();

SBUF='m';
VERIFTI();

SBUF='b';
VERIFTI();

SBUF='e';
VERIFTI();

SBUF='r';
VERIFTI();

SBUF=' ';
VERIFTI();

SBUF=':';
VERIFTI();

SBUF=' ';
VERIFTI();

unite='1';

SBUF=unite;
VERIFTI();

SBUF=unite;
VERIFTI();

SBUF=unite;
VERIFTI();

SBUF=unite;
VERIFTI();

SBUF=unite;
VERIFTI();

SBUF=unite;
VERIFTI();

FIN:
goto FIN;

}



void VERIFRI()reentrant
{
        DEBUT:
        if (RI==0)
        {
        goto DEBUT;
        }

        else
        {
        RI=0;
        }
}

void VERIFTI()reentrant
{
        DEBUT:
        if (TI==0)
        {
        goto DEBUT;
        }

        else
        {
        TI=0;
        }
}

Parents
  • Thank you very much for your dedication.

    I don't understand "you DO have a 'wild' write to the position that is unite/cent FIND IT."

    is there somewhere in the rest of your code a write to an absolute address? :

    All of my code is here. As you can see I declare 3 variables at the beginig o "unite, "diz", and "cent", but actually only "unite" is used. When I have solved my problem I can go further, and use the other variable.

    My complete code is :

    
    #include <REG51.H>
    void verifri();
    void verifti();
    
    void led_chenillard()
    {
    
    data unsigned char diz;
    data unsigned char cent;
    data unsigned char unite;
    
    
    SM0=0;                          //UART en mode 1
    SM1=1;                          //UART en mode 1
    SM2=0;                          //Gestion multiprocesseur inactive
    REN=1;                          //Reception active
    
    TMOD=0x20;                      //Config Timer 1 en mode 2 et mode temporisateur
    TH1=255;                        //56000 Bauds
    TR1=1;                          //Active le timer 1
    
    TI=1;
    
    
    
    SBUF=0x0C;                  //Efface écran
    verifti();                      //Vérifie si l'envoie au PC est terminé
    
    
    SBUF=0x0C;                  //Efface écran
    verifti();                      //Vérifie si l'envoie au PC est terminé
    
    SBUF='S';
    verifti();
    
    SBUF='e';
    verifti();
    
    SBUF='r';
    verifti();
    
    SBUF='i';
    verifti();
    
    SBUF='a';
    verifti();
    
    SBUF='l';
    verifti();
    
    SBUF=' ';
    verifti();
    
    SBUF='n';
    verifti();
    
    SBUF='u';
    verifti();
    
    SBUF='m';
    verifti();
    
    SBUF='b';
    verifti();
    
    SBUF='e';
    verifti();
    
    SBUF='r';
    verifti();
    
    SBUF=' ';
    verifti();
    
    SBUF=':';
    verifti();
    
    SBUF=' ';
    verifti();
    
    
    unite='1';
    
    P2='1';
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    P1=unite;
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    while (1);
    
    }
    
    
    
    void verifri()
    {
            while (RI==0);
            RI=0;
    }
    
    void verifti()
    {
            while (TI==0);
            TI=0;
    }
    
    

Reply
  • Thank you very much for your dedication.

    I don't understand "you DO have a 'wild' write to the position that is unite/cent FIND IT."

    is there somewhere in the rest of your code a write to an absolute address? :

    All of my code is here. As you can see I declare 3 variables at the beginig o "unite, "diz", and "cent", but actually only "unite" is used. When I have solved my problem I can go further, and use the other variable.

    My complete code is :

    
    #include <REG51.H>
    void verifri();
    void verifti();
    
    void led_chenillard()
    {
    
    data unsigned char diz;
    data unsigned char cent;
    data unsigned char unite;
    
    
    SM0=0;                          //UART en mode 1
    SM1=1;                          //UART en mode 1
    SM2=0;                          //Gestion multiprocesseur inactive
    REN=1;                          //Reception active
    
    TMOD=0x20;                      //Config Timer 1 en mode 2 et mode temporisateur
    TH1=255;                        //56000 Bauds
    TR1=1;                          //Active le timer 1
    
    TI=1;
    
    
    
    SBUF=0x0C;                  //Efface écran
    verifti();                      //Vérifie si l'envoie au PC est terminé
    
    
    SBUF=0x0C;                  //Efface écran
    verifti();                      //Vérifie si l'envoie au PC est terminé
    
    SBUF='S';
    verifti();
    
    SBUF='e';
    verifti();
    
    SBUF='r';
    verifti();
    
    SBUF='i';
    verifti();
    
    SBUF='a';
    verifti();
    
    SBUF='l';
    verifti();
    
    SBUF=' ';
    verifti();
    
    SBUF='n';
    verifti();
    
    SBUF='u';
    verifti();
    
    SBUF='m';
    verifti();
    
    SBUF='b';
    verifti();
    
    SBUF='e';
    verifti();
    
    SBUF='r';
    verifti();
    
    SBUF=' ';
    verifti();
    
    SBUF=':';
    verifti();
    
    SBUF=' ';
    verifti();
    
    
    unite='1';
    
    P2='1';
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    P1=unite;
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    SBUF=unite;
    verifti();
    
    while (1);
    
    }
    
    
    
    void verifri()
    {
            while (RI==0);
            RI=0;
    }
    
    void verifti()
    {
            while (TI==0);
            TI=0;
    }
    
    

Children