User Manual

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Siemens CP 343-1 BACnet – 6FL4343-1CX10-0XE0 CM1N9291en_02
Building Technologies 17 Sep 2009
The standardized transport protocol UDP is used for BACnet/IP. In contrast to
TCP, UDP is a transport protocol for wireless communications.
The Ethernet IP address comprises IP address, subnet mask and default gateway.
BACnet devices within a subnet have the same subnet mask.
BACnet also employs broadcasts to communicate data, i.e. all data receive
notification at the same time. Ethernet IP routers block broadcasts making direct
connection of an Ethernet subnet impossible. A BBMD (BACnet Broadcast
Management Device) allows for distributing broadcasts. DESIGO S7 and DESIGO
PX can be deployed as BBMDs.
Devices with integrated BBMD functionality, e.g. DESIGO automation stations, do
not generally allow for DHCP, i.e. automatic IP address assignment in networks.
All S7 stations connected to the network can be remote programmed using PD/OP
communications.
S7 routing allows for cross-network use of PD communications.
Operating and monitoring devices and PCs (SOFTNET-S7 or CP 1613 A2 with S7-
1613) help connect S7-300 (server only) to S7-400.
S5-compatible communications with SEND/RECEIVE offers a simple and
optimized interface for communications based on Layer 4.
Max 8 KB data can be transmitted per incident.
This interface allows for using:
− TCP transport connections
− UDP
− Multicasts for UDP
Open IE and S5-compatible communications is used to communicate with
SIMATIC S5, SIMATIC S7-400 / -300 and PCs.
The function blocks required are a part of NCM S7 for Industrial Ethernet and must
be integrated in the S7 application program.
S5-compatible communications featuring FETCH / WRITE allows for direct access
to CPU data of SIMATIC S7 or SIMATIC S5.
The Multicast function can be used to simultaneously send and receive data to and
from engineered multicast members if UDP is the transport protocol.
Note
Programming device /
OP communications
S7 routing
S7 communications
Open IE- and S5-
compatible
communications