Application and properties
1.6 IT communication
The user names and passwords are configured with STEP 7 Micro/WIN 32. The
configuration file created with the Internet wizard is transferred with FTP to the CP 243-1 and
stored permanently in the file system in a file with the extension .udb. The user name and
the password of the administrator are required to be able to transfer the user configuration to
the CP 243-1.
The CP 243-1 does not support FTP access without a user name and/or password. An
anonymous login is not supported.
Simultaneous access by several FTP clients to the FTP server of the CP 243-1 is not
The FTP server is equipped with an auto logout mechanism to prevent it from being blocked
by an undefined connection abort of an FTP client.
If the FTP server on the CP 243-1 is connected to an FTP client and a second FTP client
wants to establish a connection to the FTP server, the server checks whether or not there
was FTP-based communication between it and the first FTP client during the last 60
seconds. If there was no communication, the connection to the first FTP client is terminated
and the second FTP client's request to establish a connection is accepted. Otherwise, the
connection to the first FTP client is maintained and the second FTP client's request for a
connection is rejected.
Supported FTP commands
After the HELP command is entered in the console window of the FTP client, a list of the
FTP commands supported by this client normally appears. While these commands are being
executed, they are converted internally by the FTP client into subcommands and sent to the
Some FTP clients on the market have additional commands available that are not included in
the RFC 959 standard or whose inclusion is not generally binding. There is no guarantee
that the FTP server on the CP 243-1 will support all of these commands.
In principle, all FTP clients that communicate via Ethernet and comply with RFC 959 can be
considered possible communications partners of the FTP server on the CP 243-1. This
means that communication is not only possible with PC-based FTP clients but also with FTP
clients supported by an S7-200, S7-300 or S7-400.
Operating Instructions, 03/2012, C79000-G8976-C244-02