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# 22  
Old 10-20-2014
As I don't use Minicom then I don't know its quirks but......
This assumes you have Minicom running.
Code:
-----------------------------------------------------------------------+                                  
Comp| A -    Serial Device      : /dev/ttyS0                                |                                  
Port| B - Lockfile Location     : /var/lock                                 |                                  
    | C -   Callin Program      :                                           |                                  
Pres| D -  Callout Program      :                                           |                                  
    | E -    Bps/Par/Bits       : 9600 7E1                                  |                                  
    | F - Hardware Flow Control : Yes                                       |                                  
    | G - Software Flow Control : No                                        |                                  
    |                                                                       |                                  
    |    Change which setting?                                              |                                  
    +-----------------------------------------------------------------------+

1) Change (F) to No ; this disables HW control.
2) You can leave (E) alone FTTB.
3) Connect the loopback plug to the serial port.
4) Just typing on the keyboard now should print the characters to the terminal emulator window.
5) Now try changing (G) to Yes and try again.
6) Let us know your results...
# 23  
Old 10-21-2014
From the terminal -

Code:
root@meow:/etc/apt# exec 3<>/dev/ttyS0
root@meow:/etc/apt# printf '\rW\n' >&3
root@meow:/etc/apt# cat <&3  NO OUTPUT

Minicom -

Code:
?�
   ?�
      ?�
         ?�
            ?�
               ?�

---------- Post updated at 08:34 AM ---------- Previous update was at 08:27 AM ----------

Thanks neutronscott

From the root terminal
Code:
root@meow:/home/ethan#  exec 3<>/dev/ttyS0
root@meow:/home/ethan#  printf '\rW\n' >&3
root@meow:/home/ethan#  cat <&3

?�

---------- Post updated at 11:14 PM ---------- Previous update was at 08:34 AM ----------

I don't have the loopback plug yet. ETA 28 Oct.
# 24  
Old 10-22-2014
Thanks wisecracker -

Now I have the loopback plug...

No matter how the hardware and software flow control are set..IT WORKS!!!

What is the next step?
# 25  
Old 10-22-2014
Right, you have in theory __proven__ your serial port is working; now give us a detailed description of what you intend/or_have connected to it, (e.g. modem, Arduino, etc)...

Turn off all flow control FTTB as this will rspond as a 3 wire, (possibly 2 wire with mods), system.

I am not sure if you require 8 bit data but if so set (E) to 9600 8N1, 9600bps, 8 bits, No parity and 1 stop bit. Remember RS232 by default is an NRZ device so 9600 is about the limit of reliable _error_free_ speed without some form of flow control.

Note:- HW I can help with remote networking is more the domain of the professionals on here.
# 26  
Old 10-22-2014
Wisecracker -

Thanks.

What works for me is: 9600 7E1

It is connected to a Point Of Sale scale. I wish to weigh an item and then write the weight to a file.
How do I "Turn off all flow control FTTB"
# 27  
Old 10-23-2014
I'm sure it's just an error with my modification to the command. I think the ? may be an error indication. It would help to know what type of scale it is. Does it work with 'W\n' or 'W\r\n' in printf?
This User Gave Thanks to neutronscott For This Post:
Meow613
# 28  
Old 10-23-2014
Quote:
It is connected to a Point Of Sale scale. I wish to weigh an item and then write the weight to a file.
How do I "Turn off all flow control FTTB"
As I don't use minicom then Google is your friend here...
You can set the parameters from the command line.

UNIX man pages : minicom (1)

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

Also how is the remote system set up?
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