ADAM-454114542 User's Manual
Example Program
The following program can be used as a diagnostic test for the ADAM-454114542. It will transmit a string to
COM1 and also receive a string from COM1 of the computer (a loop-back test).
Program: LOOPBACK.C
#include <dos.h>
#include <io.h>
#include <stdio.h>
#include <conio.h>
#define TIME_OUT
4000
static int base0=0x3f8;
static int base1=0x2f8;
Signal Wiring
When you run the eXample program, connect
the ADAM-454114542 terminals as follows:
P C
R x
static char rec[160];
static char cmd[160];
void main ()
{
RS-232/422
ADAM-4541
Tx
int i,timeout;
char rflag,tflag;
bioscom(0,0xE3,0); /* Set COM1 as follows: Baud Rate = 9600, Data Bits = 8, */
printf("\nInput string : ");
/* Parity = none,
Stop Bits = 1 */
gets(cmd);
while (cmd[0] != 'q' && cmd[0] != 'Q')
{
cmd[strlen(cmd)] = 0x0d;
i=0;
tflag=1;
while (tflag)
{
/* Send data */
outportb (base0,cmd[i]);
while ((inportb(base0+5) & 32) !=32);
rflag=1;
timeout=TIME_OUT;
while (rflag)
{
/* Check received data */
if ((inportb(base0+5) & 1) !=0)
{
/*Receive data */
rec[i]=inportb(base0);
if (rec[i] == 0x0d)
{
rec[i+1]='\0';
printf("\nReceived data : %s\n”,rec);
tflag=0;
}
rflag=0;
}
else
{
/* Check timeout */
timeout--;
if (timeout == 0)
{
printf("Timeout error");
rec[i+1]='\0';
rflag=0;
tflag=0;
}
}
}
i++;
}
printf("\nInput command : ");
gets(cmd);
}
}
