9 Further Notes on Operation
B3L−51
CP 343-1 Lean for Industrial Ethernet / Manual Part B3L
Release 03/2007
C79000-G8976-C198-04
S The connections on which a job on the communication bus with a data length >
240 bytes is being processed are aborted temporarily.
S FETCH/WRITE connections are temporarily aborted.
On the FC interface in the user program, the condition codes made up of the
DONE, ERROR and STATUS parameters must be evaluated in FC11 / FC12.
9.6 Special Features of IP Configuration
Configured S7 connections cannot be operated if the IP address is assigned
over DHCP
Notice
If you obtain the IP address over DHCP, any S7 connections you may have
configured will not work. Reason: The configured IP address is replaced by the
address obtained over DHCP during operation.
9.7 Reserved Port Numbers
The following local port numbers are reserved; You should not use these for other
purposes in the connection configuration.
Table 9-1 Reserved Port Numbers
Protocol
Port number Service
TCP 20, 21 FTP
TCP 25 SMTP
TCP 80 HTTP
TCP 102 RFC1006
TCP 135 RPC−DCOM
UDP 161 SNMP_REQUEST
UDP 34964 PN IO
UDP 65532 NTP
UDP 65533 NTP
UDP 65534 NTP
UDP 65535 NTP
