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# 29  
Old 10-23-2014
Thank you newronscott and wisecracker.

" It would help to know what type of scale it is. Does it work with 'W\n' or 'W\r\n' in printf?"

From the root terminal -

Code:
root@meow:/var/www#  exec 3<>/dev/ttyS0
root@meow:/var/www#  printf '\rW\n' >&3
root@meow:/var/www# cat <&3

No output
Code:
root@meow:/var/www#  exec 3<>/dev/ttyS0
root@meow:/var/www#  printf 'W\r\n' >&3
root@meow:/var/www# cat <&3

01.755LB
00

[/CODE]


1.755is the weight of the item on the scale.

"Again what is connected to your serial port, NOT what you are trying to connect to?"

The scale.
# 30  
Old 10-23-2014
Quote:
"Again what is connected to your serial port, NOT what you are trying to connect to?"
The scale.
So you have a scale local to you that you can see and physically connect to?

This would have to be connected to the serial port using a cable then? Yes?
(This was the answer I was looking for.)

Does the scale require a Null Modem Cable or an Extension type?
If it is an Extension type then connect to your serial port and use your loopback plug at the other end and try the earlier test again.

Assuming the scale has RS232 transfer; what are the serial parameters and can it be used in raw data transfer mode?
'stty' is probably your best means of changing /dev/ttyS0 transfer parameters.

Do fault diagnosis step by step.
# 31  
Old 10-23-2014
So you have a scale local to you that you can see and physically connect to? Correct
This would have to be connected to the serial port using a cable then? Yes? Correct
Does the scale require a Null Modem Cable or an Extension type? NO
The data I displayed was after connecting the scale to the computer with a serial cable.
Assuming the scale has RS232 transfer; what are the serial parameters


Code:
     | Comp| A -    Serial Device      : /dev/ttyS0                                |                                               |     B - Lockfile Location     : /var/lock                                 |                                  
    | C -   Callin Program      :                                           |                                  
    | D -  Callout Program      :                                           |                                  
    | E -    Bps/Par/Bits       : 9600 7E1                                  |                                  
    | F - Hardware Flow Control : Yes                                       |                                  
    | G - Software Flow Control : No                                        |

Can it be used in raw data transfer mode? Please Explain
# 32  
Old 10-23-2014
Quote:
Does the scale require a Null Modem Cable or an Extension type? NO
Which one is NO or is this not_applicasble/neither?

Those parameters you display seem to be /dev/ttyS0 not the scales.

Next task is to research the model type of the scales and see if there are any commands, (much akin to AT style commands for modems), to see if you can alter serial parameters to the scales from your terminal emulator, (minicom?). Otherwise you are in the long haul of trial and error.

I have no experience with the quirks of minicom so I can't help with that but the man page should be of help...
This User Gave Thanks to wisecracker For This Post:
Meow613
# 33  
Old 10-23-2014
Thanks wisecracker -

Which one is NO ? Both
Those parameters you display seem to be /dev/ttyS0 not the scales. Correct

I'll see what I can do, and keep you posted
# 34  
Old 10-27-2014
wisecracker and neutronscott -

I have a C program which will do what I want.

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;

            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 );
                fclose(fp2);
            
            fclose(fp1);
   }

and a PHP script that calls the progarm.

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/scale`;
            echo $output;
            
?>

        </body>
</html>
When I run the PHP script, opening the serial port fails..

Code:
initiation error.

# 35  
Old 10-27-2014
It might still be open. Did you exit the shell that you used to open ttyS0?
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