Serial Communication

You won't need a C program to do this. A program will just consider all of these parameters as just numbers to be loaded into a register.

That is correct, what he can do is add a transistor to the TX driver to pulse a laser diode, and connect a phototransistor to the RX input to receive the laser beams, will need two such circuits.

I wander how's he gonna manage to aim the two transceivers...

Regards

Figure 7. A sample code listing in Borland C++ 3.1 that can be used for full-

duplex communication between two computers. The program can be used to test a

single transceiver simply by pointing the laser at the photo-transistor.

/****************************************************

**

** Laser Pointer RS-232 Transceiver

** Copyright (c) 1997 GKDesign

** 24th May 1997 George Katz

** Data Transmitted @ 9600 bps

**

*****************************************************/

#include <dos.h>

#include <stdlib.h>

#include <conio.h>

#include <bios.h>

#include <stdio.h>

#define COM1 0

#define COM2 1

#define DATA_READY 0x100

#define TRUE 1

#define FALSE 0

#define ESC_KEY '\x1b'

#define SETTINGS ( _COM_9600 | _COM_CHR8 | _COM_NOPARITY | _COM_STOP1)

void clear_line(int line)

{

int i;

gotoxy(1,line); // clear a whole line

for(i=0;i<80;i++)

printf(" ");

}

int main(int argc, char *argv[])

{

int in, out, status, done = FALSE;

int curs_rx=0,curs_ry=15,curs_tx=0,curs_ty=4;

int com_port=COM1;

if (!(argc == 2 && (argv[1][0] == '2' || argv[1][0] == '1')))

{

printf("Usage: LASER [1|2]\nwhere 1 = Com port 1\n 2 = Com port

2\n");

exit(-1);

}

if (argv[1][0]=='2') // select com port

com_port = COM2;

else

com_port = COM1;

bioscom(_COM_INIT, SETTINGS, com_port); // Initialize serial port

clrscr();

printf(" GKDesign (c) 1997 Laser Transceiver Communicator

V1.1\n");

printf(" Press [ESC] to exit program\n");

printf("__________________________________ Sent Data

___________________________________");

gotoxy(1,13);

printf("________________________________ Recieved Data

_________________________________");

while (!done) {

dUmMy= bioscom(_COM_STATUS, 0, com_port); // recieved data?

if (status & DATA_READY)

if ((out = bioscom(_COM_RECEIVE, 0, com_port) & 0x7F) != 0) { //

get data

if (curs_rx < 78) // move cursor

curs_rx++;

else {

curs_rx = 1; // at end of line

if (curs_ry < 23)

curs_ry++;

else

curs_ry = 15;

clear_line(curs_ry);

}

gotoxy(curs_rx,curs_ry); // goto correct screen location

putch(out); // print the character

}

if (kbhit()) {

if ((in = getch()) == ESC_KEY) // check for ESC key

done = TRUE;

if(!in) // read an extended character

in = getch();

if (curs_tx < 78) // position cursor

curs_tx++;

else {

curs_tx = 1; // at end of line

if (curs_ty < 12)

curs_ty++;

else

curs_ty = 4;

clear_line(curs_ty);

}

gotoxy(curs_tx,curs_ty); // goto correct screen location

putch(in); // print the character

bioscom(_COM_SEND, in, com_port); // output data

}

}

clrscr();

return (0);

}

http://www.qsl.net/n9zia/wireless/laser/laser.htm

sir, if i am using ubuntu terminal for executing above code in transmitter pc then where i can view in the receiver pc?