Devolo G3-PLC Modem 500k, Руководство пользователя

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Configuration
devolo G3-PLC Modem 500k
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is sent as a byte inside a packet over IP. These bytes are simply combined into packets
using the "Maximum buffer size" and "Timeout" parameters, so no individual bytes are
sent in one packet.
Since a G3-PLC modem is required for transmission from Ethernet to PLC, the follow-
ing set-up is used for two separate, simultaneous serial connections:
For logical reasons, the local G3-PLC modem is configured as a PAN coordinator,
while the other G3-PLC modems operate as PAN clients in the same PAN. The PAN
coordinator operates without piping the serial interface. It is used only as a transition
from Ethernet to G3-PLC.
Both remote G3-PLC modems have enabled piping with suitable interface parameters
and buffer size as well as timeout settings. The role configured in the IP network is usu-
ally "Server", where any (even the same) ports can be selected.
This enables the master to establish TCP connections there or send UDP packets there
by knowing the IP addresses of the two remote G3-PLC modems. This allows the mas-
ter to communicate with all connected serial devices.
The two G3-PLC modems can also be configured as clients, which requires that they
have the IP address of the master and two different ports of the master configured. In
this case, each of them establishes a TCP connection to the master, which can then dif-
ferentiate between the devices based on the port in use.
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Virtual serial bus
In the scenario above, a master connected over a LAN can already communicate with
multiple interfaces from multiple G3-PLC modems simultaneously and the master can
treat them as a serial bus if programmed accordingly.
If the master has an RS485 port, however, only the connection to a G3-PLC modem
and its RS485 port is possible with normal piping. The G3-PLC modem connected to
the master and configured as a server can open an additional port where clients can
connect if they meet two requirements: they all receive data from the master and their
data are sent to all other clients and to the master.
The local G3-PLC modem assumes the role of the server and the option Communicate
with multiple devices via IP like a serial bus is activated and a port is specified. All
Fig. 8