Sending IP telegramm from Homesever to port 23 (telnet)

[JeroenV]

Hello,


I have a question about sending IP telegrams from a homeserver to an
Extron audio matrix switch.

For the communication between the audio matrix switch and the
Homeserver we need to send a string (ASCII) command to an IP address
with port 23 like TELNET commands. The problem is that the homeserver
needs to send this String command many times before the Extron audio
matrix switch reacts to this command.

I already asked this question to Extron but they say that when it
works with external TELNET programs like Hyperterminal that it has to
work with other programs as well.

I am sending the IP telegram as a String tekst with a carriage return
at the end.

Does someone knows a solution for this problem?

Is there a way around in the Homeserver to communicate with a TELNET
device?

I hope someone can help me out.


Best regards,

Jeroen Verbocht

[TRex]

can you send a screenshot from:
l
*logic
*Web/IP Telegramme senden?

[JeroenV]

Hello TRex,


I'm using a button on a visu page. As "befehle" I have linked directly "IP telegramm senden" to it.

I am not using any logic.

I have attached screenshots from the IP telegram text which I'm sending to the Extron audio matrix switch.


Thanks so far.

[NilsS]

Hi,

if you enter those strings from Hyperteminal, does the connection close after each command?

If not, you have to add a close command after the ASCII String, else the connection stays open and waits for a timeout.

[JeroenV]

Hello NilsS,

Do you mean with Hyperterminal that you have to connect again by pushing the "telephone" symbool after you have send a command and want to send a new command?

It doesn´t disconnect when sending the command "03*06$" After the ASCII sign "$" the audio matrix switch switches the input "03" to the output "06".

With the Homeserver after the ASCII string the matrix switch switches the input to the output after random attempts. It must be switching after the first attempt.

How can I monitor if the Homeserver disconnects after sending the ASCII command?

What could be a closing command in ASCII format? A cariage return or Line feed?

[NilsS]

you can try in Hyperterminal, maybe "exit" + crlf or "quit" + crlf
or "03*06$" +crlf + "exit"+quit" or "\x03"(ctrl-c) +

[swenga]

Hello,

actually it would be nice to knwo exactly, if the incoming telnet commad executes the command or the closure of the telnet session.

I would recommend to observe this beahviour with an Ethernet Sniffer (e.g. Wireshark) once when sending the command via Telnet-Session and once from the homeserver and observe the differences in the datagrams.

best regards,

Swen

[JeroenV]

Hello Swen,

I have monitored the session with Wireshark between the Extron matrix switch and the Homeserver. and the Extron matrix switch in connection with a telnet session program (Hyperterminal).

The difference between the homeserver or Hyperterminal in connection with the Matrix switch is that the Homeserver sends all ASCII characters at once. Even if I put character after character in separate text blocks (dateblöcke), the Homeserver put all characters to one String before it sends the command to the Matrix switch.

Hyperterminal however sends a ASCII character after each key stroke. With Hyperterminal the Matrix switch reacts when it receives the “$” character. It gives a response character string with the connected Input-output tie. The connection remains open even after sending a character string command.

From the Homeserver the Matrix switch reacts randomly. Sometimes I have to send the command several times before the Switch reacts with its response character string.

It looks like the Homeserver cannot send a String character after character. Or the Homeserver is to fast with opening the session and sending the Character string.


Do you have an idea what could help me?

[swenga]

Hello Jeroen,

telnet is more a dynamic protocol with the server providing prompts and the user interactively inputting data. I think the datagram sending portion of the homeserver was more intended for direct stack communication, where all datagrams come out as a burst.

An idea would be to try a sequence (in the chapter EIB-Control). There you can define data content beeing set to the comms object, triggering the sending and define sleeps in between. I hope that the TCP-session will stay alive during the sequence, if it is closed after each datagram the idea is crap.

Wish you luck, Swen