76343/4/5 | English, Revision 05 | Date: 23.02.2022
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Serial Interface – Chapter 8
8.2 Network-Configuration Modes
Several modes are available for the use of the serial interfaces:
1.
TCP/IP-Server-Mode:
With this setting, the HG G
76343/4/5 opens a socket in the
Listen
mode and
waits for a connection on a specific port (Local port). The HG G
76343/4/5 only
keeps one connection at a time. In this mode, only the port number is specified
as a parameter.
2.
TCP/IP-Client-Mode:
The HG G
76343/4/5 actively opens a TCP connection on the specified port of
another network node. This network node can be another HG G
76343/4/5 or a
computer that is waiting for a connection on the specified port. In addition to
the port number (remote port), the IP address of the communication partner
must be specified in this mode (Server IP).
3.
UDP/IP-Mode:
In the UDP mode, the HG G
76343/4/5 waits on the
local port
for data sent via
UDP / IP. The serially received data are sent via UDP / IP to the
remote port
of
the remote IP address. If the communication partner is not known, the remote
IP address including remote port can be set to
0.0.0.0
or
0
. In this case, the
76343/4/5 inherits the sender IP + port information from the data packet
initially arriving at the
local port
. The UDP mode should be used in cases where
e.g. a separation of the communication partners occurs more frequently. How
-
ever, it must be noted that the UDP protocol does not ensure the correct deliv
-
ery of the data.
4.
Printerserver-Mode:
In print server mode, the HG G
76343/4/5 starts a TCP / IP socket in server
mode that is waiting for connections on port 9100.
8.3 Keep Alive Settings
Once a TCP / IP connection is established, it remains until one of the communication
partners closes the connection. If the connection between the HG G
76343/4/5 and
the network communication partner is interrupted without the TCP / IP connection
being closed before, the HG G
76343/4/5 may not reconnect.
The
keep alive
function transmits an
empty
data packet to the other at the time in
-
terval of
keep alive period
. If there is no response for the number of times defined
with
keep alive probes
, the HG G
76343/4/5 resets the TCP socket and restarts the
connection. Especially if the radio modem is working in the TCP client mode, you
should activate the
Keep alive
function by setting the values for
keep alive period
and
keep alive probes
to values >
0
.
8.4 Handshake Mode Settings
This section defines how the readiness to transmit or receive data between the serial
communication partners is handled. With the signals RTS, DTR, the HG G
5 shows receive readiness. The signals CTS, DSR are input signals via which the con
-
nected serial device shows its readiness to receive.
