Hi Farshid,

i already using #include <string.h>, and already have been trying to use strcat, strcpy in my code, but no luck.

#include <string.h>

xdata char S1[50];

void printlcd (char Pos, char *Str)
{
while(*Str)
{
.....
}
}

void main(void)
{
strcpy (S1, "HELLO");
strcat (S1, " WORLD");

printlcd (0, S1);
}