double Calc_VZout(double Read_Sim, double Ik, double Vref_uut, double Zout)
{

     double Isim = 0;
    double Vzsim = 0;
     double temp = 1;
     double temp2;

    temp2 = (temp - Read_Sim);

    if (temp2 > 0)
    {

        Isim = log(temp2) * Ik;// <= Process Exit Code: 2

        // But this will work => Isim = log(.234) * Ik;

    }

    Vzsim = (Isim * Zout);

    return (Vref_uut - Vzsim);

}

Output:
> "make.exe" all

make -C ../libnerdkits
make[1]: Entering directory `C:/WinAVR-20090313/avr/libnerdkits'
make[1]: Nothing to be done for `all'.
make[1]: Leaving directory `C:/WinAVR-20090313/avr/libnerdkits'
avr-gcc -g -O0 -Wall -mmcu=atmega328p  -Wl,-u,vfprintf -lprintf_flt -Wl,-u,vfscanf -lscanf_flt -lm -o zsensim.o zsensim.c ../libnerdkits/delay.o ../libnerdkits/lcd.o ../libnerdkits/uart.o
c:/winavr-20090313/bin/../lib/gcc/avr/4.3.2/../../../../avr/lib/avr5\libc.a(log.o): In function `log':
(.text.fplib+0x46): relocation truncated to fit: R_AVR_13_PCREL against symbol `__addsf3' defined in .text section in c:/winavr-20090313/bin/../lib/gcc/avr/4.3.2/avr5\libgcc.a(_addsub_sf.o)
c:/winavr-20090313/bin/../lib/gcc/avr/4.3.2/../../../../avr/lib/avr5\libc.a(log.o): In function `log':
(.text.fplib+0x4e): relocation truncated to fit: R_AVR_13_PCREL against symbol `__addsf3' defined in .text section in c:/winavr-20090313/bin/../lib/gcc/avr/4.3.2/avr5\libgcc.a(_addsub_sf.o)
make.exe: *** [zsensim.hex] Error 1

> Process Exit Code: 2
> Time Taken: 00:01

I FOUND THE SOLUTION!!!

THANKS to mrobbins!

Microcontroller Programming » Trouble with the log10 function

June 02, 2010 by mrobbins (NerdKits Staff)

Hi Rufus, Does your compiler error say something like "relocation truncated to fit"? If so, give this a try: 1) In the Makefile, remove "-lm" from the end of the LINKFLAGS line:

1 LINKFLAGS=-Wl,-u,vfprintf -lprintf_flt -Wl,-u,vfscanf -lscanf_flt
View Original 2) In the Makefile, add "-lm" to the end of the LINKOBJECTS line:

1 LINKOBJECTS=../libnerdkits/delay.o ../libnerdkits/lcd.o ../libnerdkits/uart.o -lm
View Original 3) Run "make". This simply rearranges the order in which the compiler/linker bundles the math code with your code, ensuring that the math code comes last. For reasons that are a little bit voodoo, this tends to make it work. (There's a bug report about this issue from a while ago, but not too much detail in explaining it clearly.) Please let me know if that works! And if not, please post the compiler's error message. Mike