Victor Pezier

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6 years, 1 month ago.

The compiler displays Error 247 but I don't know why

Hi everyone!

I'm currently working on a program for a school project and the compiler displays an error 247 (variable or function already define) for several objects, but I can't find where the multiples definitions are from. Perhaps somebody can help me :)

Here's my code (so far) :

This file contains my functions

#include "mbed.h"
#include "options.h"

DigitalIn freq1(p8);
Timer timer;

float compteur()
{
    float T=0;
    if(freq1==1)
    {
        timer.start();
        if(freq1==1)
        {
            T = timer.read();
        }
    }
    wait(1);
    timer.stop();
    timer.reset();        
    return T;
}

float frequence(float periode)
{   int f;
    f = (1/periode);
    return f;
}

int receive(Serial pc) 
{   int data[5];
    pc.scanf("%d", data);
    pc.printf("%d", data);
    return 0;
}

int transmit(int retour) {
int n=11;
int a;

int c = 0 ;
    while( n >= 1 ) {
        a = n % 2;
        if ( a == 1 ) {
            c = c + 1;
        }
        n = n / 2;
    }
    return 0;
}

This one is the main

#include "mbed.h"
#include "options.h"

Serial in(p9, p10);
Serial pc(USBTX, USBRX);
Serial out(p13, p14);

int main()
{
    pc.format(7, Serial::Even, 1);
    pc.baud(9600);
    in.format(7, Serial::Even, 1);
    in.baud(9600);
    out.format(8, Serial::Even, 1);
    out.baud(9600);
}

And finally this one is my header file

#ifndef OPTIONS_H_INCLUDED
#define OPTIONS_H_INCLUDED

#include "mbed.h"
#include "compt.cpp"


float frequence(float);
int receive(Serial);

#endif

1 Answer

Jenny Plunkett
6 years ago.

Hi Victor,

For which target/board are you trying to compile for? Also, in your last header file, on line 5 #include "compt.cpp" that code is going to essentially copy all of the contents from your compt.cpp file into your header file, which may be causing the multiple definitions.

- Jenny, team Mbed

Accepted Answer

Hi Jenny,

Thanks for your answer, it was really helpful. by the way, I'm using a LPC1768. I didn't realize that my header file was causing multiple definitions. Again, thanks a lot!

Victor

posted by Victor Pezier 27 Mar 2018