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Montage- und Anschlussanleitung / Funk-Empfänger
Mounting and wiring instructions / Wireless receiver
Instructions de montage et de câblage / Récepteur sans fil
Istruzioni di montaggio e collegamento / Ricevitore wireless
Instruções de montagem e instalação / Receptor sem fio
Инструкция по монтажу и подключению / Радиоприемник
//
RF Rx EN868 TCP/IP / RF Rx SW868/SW915/SW917/SW922 TCP/IP V2
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English
TCP
In contrast to UDP/IP the TCP/IP is a safe network connection. Trans-
mitted packages are confirmed and are in case of loss or transmission
error are transmitted automatically again. The order of the network
transmissions corresponds to the order of the received
wireless telegrams.
IP datagram
IP header
TCP header
wireless telegram (TCP data)
TCP datagram
Similar to the UDP datagram the TCP datagram is integrated in the IP
datagram. The TCP header contains, besides the source port and tar-
get port, further information that identify the datagram clearly. The
header has a typical length of 20 bytes.
TCP server
If a switch is configured as »TCP server« in the steute ethernet Gate-
way, it opens a so-called socket with the switch port number saved for
this switch (may only be assigned once) and its IP address (the IP ad-
dress set for this switch is not considered) and remains in the status
»passive open« or »listen«. If the network receiver (Client) now wants
to connect, it also opens a socket with its own IP address and a still
free port number and transmits a »SYN« package (synchronize) to the
server. The Gateway (server) responds with a »SYN-ACK« (acknow-
ledgement) which will in turn be confirmed by the client with »ACK«.
The connection is now built up. Now all wireless telegrams occurring
at the Gateway are transmitted to the client and must be confirmed
with »ACK« there. If this confirmation by the client is missing, the tele-
gram will be repeated three times. If the communication is perma-
nently interrupted, the Gateway will close the connection and return to
the »passive open« mode. If no error occurs, the connection remains
active until the client terminates it. Only one client can register to one
TCP server socket!
TCP client
In the configuration »TCP client« the Gateway starts the connection by
transmitting the »SYN« package. If the saved network receiver is not
yet in »passive open« status, a new trial is carried out every 2 seconds.
If the server responds with »SYN-ACK«, a connection is built up by
transmitting »ACK« again. The client keeps up the connection as long
as the server is active. Received wireless telegrams are now transmit-
ted from the client to the server. If there is no communication for more
than 10 seconds, the client transmits a »Keep alive« telegram to check
the connection.
ModbusTCP
The TCP/IP Gateway provides a ModbusTCP server (standard port 502).
The TCP/IP Gateway provides the ModbusTCP server in addition to the
individually configurable sensor connections. The sensors must be
taught-in for ModbusTCP access and configured as »active«. At this
port, the server waits for the ModbusTCP request. A client such as a
PLC connects to this port and polls the switching data cyclically.
With ModbusTCP, the information is organised in 16-bit registers. The
client specifies in its request from which register number and over
how many registers information is to be exchanged. The functions
»Read Input Registers« and »Loopback Diagnostic Test« (function code
4 and 8) are implemented.
According to the ModbusTCP definition, a maximum of 125 registers
can be transmitted with one request. For this reason, two address
ranges are provided. Two address ranges are provided. From address
1000, detailed information on each sensor can be requested. From ad-
dress 2000, a compressed overview of the switching states of all sen-
sors is available.
Address range Features
1000 .. 1799
20 registers are reserved for each switch. The in-
formation of the first switch in the overview table
of taught-in switches is located from address
1000, the next from 1020, etc.
The first two registers contain a 32-bit time code
(unsigned, resolution 1 second, big-endian
coded, time span since last telegram reception
in s).
This allows the receiver to evaluate whether the
information is new enough and may be evalua-
ted, warnings are issued, etc.
The next 16 registers contain the complete radio
telegram received last. For easier evaluation, each
received byte is reported in a 16-bit register, i.e.
the top 8 bits here are always 0x00.
If no telegram has been received from the relevant
switch since power-up of the Gateway, 0xFFFF is
reported here for each register.
2000 .. 2039
One register is stored per switch. The register
shows the switch status, independent of the
radio protocol used. Due to the small address
range, all switch states can be read in with one
access, but without additional information such
as the actuality.
