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# 50  
Old 10-30-2014
Okay, so minicom is using serial port timeouts. Let's see how that works for this.

Code:
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <stdio.h>
#include <string.h>

#define STDOUT_FILENO 1

int main() {
        const char *str="W\r\n";
        char buf[64];
        int pos=0;

        int fd=open("/dev/ttyS0", O_RDWR);
        if (fd < 0) {
            perror("Couldn't open");
        }

        // These WERE saved from when minicom was running, right?
        system("stty -F /dev/ttyS0 1:0:80000dad:0:3:1c:7f:15:4:5:1:0:11:13:1a:0:12:f:17:16:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0");

        write(fd, str, strlen(str));

        fprintf(stderr, "Wrote W\n");

        tcdrain(fd);

        while(read(fd, buf+pos, 1) == 1)
        {
                fprintf(stderr, "Read 0x%02x\n", (unsigned char)buf[pos]);
                if(buf[pos++] == '\n') break;
        }

        buf[pos]='\0';

        printf("got line:\n%s", buf);
}

If "W\r\n" doesn't work try "W\n"

You can't remote into your machine? Trial-and-error with a 24 hour delay between trials...
This User Gave Thanks to Corona688 For This Post:
wisecracker
# 51  
Old 10-31-2014
Corona688 -

Thanks.

// These WERE saved from when minicom was running, right? - Regrettably no.

I'll make the appropriate changes in the C program when I get home [approx 8pm EST] and keep you posted.

---------- Post updated at 06:27 PM ---------- Previous update was at 12:23 PM ----------

Corona688 -

Thanks -

You can't remote into your machine? Trial-and-error with a 24 hour delay between trials...
Free standing computer at home. Can't remote into it from my other job.

Sorry

---------- Post updated at 11:45 PM ---------- Previous update was at 06:27 PM ----------

IT WORKS!!

The thing that did it, as you sugessted was to initialize the port in the program.

Here is your code, as modified -

Code:
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <stdio.h>
#include <string.h>

#define STDOUT_FILENO 1
#define BAUDRATE B9600
#define MODEMDEVICE "/dev/ttyS0"


int main(void) 
{

        const char *str="W\r\n";
        char buf[64];
        int pos=0;
        int n;
        char buff[20];
        FILE *fp1, *fp2;   
        

        fp1 = fopen(MODEMDEVICE, "w+");
        system("stty -F /dev/ttyS0 1:0:80000dad:0:3:1c:7f:15:4:5:1:0:11:13:1a:0:12:f:17:16:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0");

        fp2 = fopen("testfile.txt", "w+");

        fprintf(fp1, "%s","W\r\n");
        fread(buff,7,1, fp1);
        rewind(fp2);
        fwrite(buff, 1, 7,fp2 );

}

It even works in my original program -

Code:
       #include <stdio.h>
       #include <fcntl.h>
       #include <sys/stat.h>
       #include <termios.h>
       #include <string.h>

        #define BAUDRATE B9600
        #define MODEMDEVICE "/dev/ttyS0"

        int main(void)
        {
            int n;
            char buff[20];

            FILE *fp1, *fp2;

            system("stty -F /dev/ttyS0 1:0:80000dad:0:3:1c:7f:15:4:5:1:0:11:13:1a:0:12:f:17:16:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0");
 
            fp1 = fopen(MODEMDEVICE, "w+");

            if(fp1 == NULL)
            {
                printf("initiation error. \n");
                return 1;
            }

            fp2 = fopen("testfile.txt", "w+");

            fprintf(fp1, "%s","W\r\n");
            fread(buff,7,1, fp1);
            rewind(fp2);
            fwrite(buff, 1, 7,fp2 );
        }

and in the PHP script...

PHP Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">

<html>

    <head>
        <title>Test Scale</title>
    </head>
        <body>
        <strong>
            <div align='center'>
                  <h3>Test Scale</h3>
            </strong>
                    </div>

<?php
            error_reporting(E_ALL | E_NOTICE);
            ini_set('display_errors','1');
            echo 'hello';
            $output = `/var/www/scale4`;
            echo $output;
            
?>

        </body>
</html>
I thank all of you for your patience and help. This lifts a tremendous burden off my head!!!
This User Gave Thanks to Meow613 For This Post:
Corona688
# 52  
Old 10-31-2014
There is one set of final tests to do now.

You have experienced a random power down on the computer side so you now need to randomly power down the scales.

Then check to see if you still have the two talking when you power thst scales back up.

Similarly simulate a break in comms by disconnecting the the serial port to the outside world whilst in use and if needed code to suit.

These are real world events.

(Nice one Corona688.)
# 53  
Old 10-31-2014
I am very glad that it works for you! Smilie

...but you should not be using stdio for device files! I used open/read/write/close for a reason!

stdio is just not meant for that. At the very least, please disable the line-buffer with setvbuf to prevent it from freezing when absolutely nothing's wrong...

system("stty"); almost feels like cheating, but sometimes, the C way is just not worth fighting with.
Last edited by Corona688; 10-31-2014 at 12:49 PM..
This User Gave Thanks to Corona688 For This Post:
Meow613
# 54  
Old 11-02-2014
wisecracker -

Similarly simulate a break in comms by disconnecting the the serial port to the outside world whilst in use and if needed code to suit.
FAILED

I cannot even access the COM with minicom.. ugh
I will not even try to simulate a power failure until this is solved.

Thanks for your "real world" tests.

---------- Post updated at 12:16 AM ---------- Previous update was at 12:03 AM ----------

Another Note -

It requires minicom to be running for the program to work. If I disconnect the COMM, minicom can only be activated by closing it and restarting.

Thanks for the testing
# 55  
Old 11-02-2014
Welcome to the real world... ;o)

You might have to do a compete power down and cold start of the computer to _reset_ the port and gain full access again.

Quote:
It requires minicom to be running for the program to work. If I disconnect the COMM, minicom can only be activated by closing it and restarting.
Is this a function of the forced error or have you found it out by _accident_?
# 56  
Old 11-02-2014
wisecracker -

The real world can be nasty!

This C code dies with a segmentation fault.

Code:
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <stdio.h>
#include <string.h>

#define STDOUT_FILENO 1
#define BAUDRATE B9600
#define MODEMDEVICE "/dev/ttyS0"


int main(void) 
{

        const char *str="W\r\n";
        char buf[64];
        int pos=0;
        int n, i, d ;
        char buff[20];
        FILE *fp1, *fp2;   
        
        fp1 = open("/dev/ttyS0", O_RDWR);
        if (d < 0) 
        {
            perror("Couldn't open");
        }

        system("stty -F /dev/ttyS0 1:0:80000dad:0:3:1c:7f:15:4:5:1:0:11:13:1a:0:12:f:17:16:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0");

        fp2 = fopen("/var/www/testfile.txt", "w+");

        fprintf(fp1, "%s","W\r");
        fread(buff,7,1, fp1);
        printf("buffer elements\n");
        for(i= 0; i < strlen(buff) + 1;i++)
            printf("%c", buff[i]);
         printf("You entered the string %s\n",buff);
        rewind(fp2);
        fwrite(buff, 1, 7,fp2 );

}

Here is the PHP script that is being called...

PHP Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">

<html>

    <head>
        <title>Test Scale</title>
    </head>
        <body>
        <strong>
            <div align='center'>
                  <h3>Test Scale</h3>
            </strong>
                    </div>

<?php
            error_reporting(E_ALL | E_NOTICE);
            ini_set('display_errors','1');

            $output = `/var/www/scale4`;
            $fptr1=  fopen("/var/www/testfile.txt", "r");
            $bla = fscanf($fptr1,"%f"); //the data is always on the 2nd line
            $weight= fscanf($fptr1,"%f");
            print_r($weight);
            var_dump($weight);
            echo $weight[0];
?>

        </body>
</html>
This hopefully will be a commercial product, a Point Of Sale system for grocery stores. A situation cannot occur that will require rebooting or resetting the system. Therefore the "real world tests" that you stated must be passed under almost all situations. A UPS will help in most of the situations, but the others???
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