• "Class E" addresses: 240.0.0.0 - 247.255.255.255
• Broadcast addresses: e.g. 255.255.255.255
4.2.2 Subnet mask
If a subnet mask is specified during configuration, its structure must comply with
the general conventions defining subnet mask validity.
Please note that the validity of an IP address and an associated subnet mask are
interdependent.
4.2.3 TSAPs
The TSAPs consist of 2 bytes. The first byte specifies the connection and the second
byte is composed of the rack number and the position of the communications
module. The following value ranges apply for the first byte.
• Local TSAP value range: 16#02, 16#10 - 16#FE
• Remote TSAP value range: 16#02, 16#03, 16#10 - 16#FE
The structure of the second byte is not checked by the CP 243-1.
Defining the address of the control byte and the number of connections
Use the next dialog to specify the address of the byte in the memory address
space of your S7-200 system from which the CP 243-1 can be addressed from the
S7-200 CPU. This address depends on the position of the CP 243-1 in your
S7-200 system and on the number of outputs in your S7-200 system. If, when you
began configuring the system, you had the Ethernet Wizard determine the position
of the CP 243-1 in your S7-200 system, the Wizard will now provide you with the
address to be used.
Basically, you can determine the memory address spaces occupied by the modules
present in your S7-200 system by enabling the "Information..." entry in the
"PLC" menu in STEP 7 Micro/WIN 32. In this manner you will also find the address
under which your CP 243-1 can be addressed in your S7-200 system.
In this dialog, you can also define the maximum number of connections your
CP 243-1 should maintain in parallel at any one time. Up to 8 such connections can
be maintained. A dialog in which you can configure the connection then appears
for each connection you specify here.
Configuring the inpidual connections
The connections that you established in the previous dialog are configured in the
dialogs that follow. For each connection, you must first define whether your S7-200
system should be operated as a client or server. This will determine the structure of
the dialog.
If your S7-200 system is to be operated on the connection as a client, then you
must specify the address of the communication partner and the communications
end point ("TSAP") in this partner. Moreover, in an additional dialog, you must
specify which data is to be exchanged between your S7-200 system and the specified
communication partner. At this point you also define whether these data is to
be read or written. Up to 32 read/write commands can be defined per connection.
If your S7-200 system is operated on the connection as a server, then you can define
to which communication partner you wish to grant access to your system by
assigning an IP address. However, you can also set each server so that it always
grants access from any IP address. You must also define the communications end
point ("TSAP") in your communication partner from which you grant access to your
S7-200 system.
A Keep Alive system can be enabled for both client and server connections.
Please use the communications end points ("TSAPs") of your communication partner
specified in the configuration of that partner. In an S7-200 system, it is generated
using STEP 7 Micro/WIN 32. In an S7-300, S7-400 or OPC-based system,
use STEP 7 to do so (see also Chapter 4.4).
Note