http://www.8051projects.net/ Learn to make simple microcontroller projects, pic, 8051, avr and arm projects. download 8051 projects, tutorials, libraries, sample codes. join the microcontroller discussion forum and ask doubts regarding electronics. the best source for 8051 over internet. en-gb 2009-01-07T17:58:31-08:00 contact@nospam.com hourly 1 2000-01-01T12:00+00:00 http://www.8051projects.net/forum-t10612.html 2009-01-07T17:58:31-08:00 I know my post might look weird as I am noob, but believe me I only got time to learn uC's at night as I am really very busy in daytime with Symbian C++.Please look at the following code and let me know the mistake, here I am trying to print back a character to the hyper terminal in window OS. I wrote the code in such a way so that it can detect the character entered by user in hyper terminal and then send the same back to the hyper terminal.I know I must be doing something wrong that is why I am unable to type anything on the Hyper Terminal CODE:#include<P89V51Rx2.h>
#include<intrins.h>
#include<string.h>

void delay()

   {
    int i;
 for(i=0;i<9000;i++);
 }
 
void serial_send(unsigned char dat){
        while(!TI);
        TI = 0;
        SBUF = dat;
}
unsigned char serial_read(){
        while(!RI);
        RI = 0;
        return SBUF;
}          
                   
 void main()
   {
unsigned char i,data1;        
    TMOD=0x20;
    SCON=0x50;
    TH1=0xfd;
    TL1=0xfd;
    TR1=1;
  while(1)
        {
                char a = serial_read();
                delay();
                serial_send(a);
        }       
}              
  http://www.8051projects.net/forum-t10612.html 2009-01-07T17:58:31-08:00 Ajay I am not sure how you're able to compile it coz you are using C now.. not c++ sothis thing is not possible within the program..CODE:char a = serial_read();As per ANSI C you have to define the character at the top of program. http://www.8051projects.net/forum-t10612.html 2009-01-07T17:58:31-08:00 Ajay I am moving your post in 8051 discussion section http://www.8051projects.net/forum-t10612.html 2009-01-07T17:58:31-08:00 Ajay Sashi what paul wrote is fine just the problem is he declared the variable within the function which is not valid in C he is used to of c++ a lot i guess http://www.8051projects.net/forum-t10612.html 2009-01-07T17:58:31-08:00 sashijoseph void serial_send(unsigned char dat){ while(!TI); TI = 0; SBUF = dat;}Change to ...void serial_send(unsigned char dat){ SBUF = dat; while(!TI); TI = 0; } http://www.8051projects.net/forum-t10612.html 2009-01-07T17:58:31-08:00 say2paul Its fact... and its difficult to follow C Standards...But I will get use to it