4 Configuration
4.1 Configuration options
An S7-200 system can communicate with another S7-200 system and with anS7-300, S7-400 or OPC-based system via the CP 243-1A.
There are two methods of configuring a communication of this type in an S7-200 system: 49484
• Configuration using STEP 7 Micro/WIN 32, version 3.2.1 or higher
• Configuration using an S7-200 user program
Attention
The system can only be configured via an S7-200 user program if the CRC
mechanism has been switched off.
Since the configuration data can no longer be fully checked for consistency with
regard to intended and unintended changes after the CRC check of the CP 243-1
has been switched off, there can be no guarantee in this case that the CP or the
components connected in the network will operate correctly.
In both cases, the configuration data is stored in the data block of the S7-200 CPU.
Every time the CP 243-1 is restarted, the data is read once from that location.
Attention
To protect the configuration data of the CP 243-1 if the system goes into a novoltage
state, these data must be stored in a non-volatile data storage area of the
S7-200 CPU.
In a standard S7-200 system, the entire data block is defined as non-volatile. However,
this default setting on your S7-200 system could have been modified if
changes were made to the configuration.
If STEP 7 Micro/WIN 32 is used for reconfiguring or modifying the configuration of
the CP 243-1, the new configuration becomes effective only after the CP 243-1 is
restarted. If the S7-200 CPU changes from STOP to RUN mode after such a reconfiguration,
the CP 243-1 is automatically restarted. However, if the CP 243-1 is
configured directly in the S7-200 user program, the configuration can be enabled
by calling up the "ETHx_CFG" subroutine in the user program. Calling up the subroutine
also causes the CP 243-1 to restart.
The TCP/IP address parameter (IP address, subnet mask, IP address of a Gateway)
can either be defined during configuration or the CP 243-1 can be configured
in such a way that it dynamically retrieves the TCP/IP address parameters from a
BOOTP server while booting.
If an S7-200 system is to communicate with an S7-300, S7-400 or OPC-based system
via a CP 243-1, configure such an S7-300, S7-400 or OPC-based system using
STEP 7, version 5.1 or higher, with Service Pack 3 or higher (with NCM S7 for
Industrial Ethernet).
Note
The CP 243-1 may independently switch to another Gateway after booting due to
special network-based services ("ICMPRedirect"). After approx. 30 seconds, the
CP 243-1 switches back to the Gateway originally configured. Thus, the Gateway
actually used by CP 243-1 can temporarily deviate from the one defined in the configuration.
You can read out the Gateway the CP 243-1 is using at any particular time from the
storage area of the S7-200 CPU in which the NPB data block is stored (see Chapter
4.4.3). To do so, use the CP 243-1 diagnostics window in STEP 7 Micro/WIN 32
or make use of a user program.
4.2 Value ranges of the configuration data
4.2.1 IP address
The IP addresses to be specified at various points within the configuration must
comply with the general conventions defining IP address validity.
According to these conventions, certain IP addresses serve specific purposes.
These addresses will not be accepted by the CP 243-1. They include:
• Loopback: 127.0.0.0 - 127.255.255.255
• "Class D" addresses: 224.0.0.0 - 239.255.255.255