Siemens SIMATIC S7 Manual page 25

Declaration of the
Registration Key
REG_KEY
MODBUS / TCP communication via the integrated PN interface of the CPU
2XV9450-1MB02; Manual edition 2.1
The registration key REG_KEY must be declared for each call of the block
MODBUSPN.
The registration key REG_KEY should be stored in a global DB. Via this
global DB all MODBUSPN blocks can receive the registration key (See also
the following example).
Please proceed as follows to declare the registration key REG_KEY:
1. Copy the prepared license block DB3 of the library
"Modbus_PN_CPU" into your project. If the DB number is already
used in your project, rename the license DB.
2. Open the license DB and copy the 17 digit registration key you
received from IT4industry to the column "Initial value".
3. Declare the registration key in the data block as "initial value" to avoid
a repeated insertion after reloading the PLC. Open the data block in
the SIMATIC manager with the editor in the declaration view. Change
over to the data view via the menu "View" -> "Data View". Choose in
the menu "Edit > Initialize Data Block" – all values of the column
"initial value" are copied to "actual values".
4. Assign the value "DB3.REG_KEY" to the parameter REG_KEY of the
block MODBUSPN.
5. Transfer the changed blocks to the PLC. The registration key can be
set at run time. A STOP -> RUN transition is not necessary.
The block is now licensed for this CPU.
Licensing
5-3