Configuring Hardware and Communication Connections STEP 7.pdf

Example for Converting to a GD Table (After Compiling)
Configuring Global Data Communication
GD Identifier CPU 300 (1) CPU 300 (2) CPU 300 (3) CPU 300 (4)
GD 1.1.1 > MW0 IW0 IW0
GD 2.1.1 > MW100:4 IW30:4 IW20:4 IW30:4
Tip
It may be advisable to determine a CPU as the receiver for a GD packet although
the packet is not required for these CPUs (as CPU 4 in the example above). If the
sender and the receiver CPUs are the same, the number of GD circles can be
reduced in this way, for example, for the sender CPU. In the example above, CPUs
1,2, and 3 would then only form one GD circle because both GD packets would be
grouped together to form one GD packet.
Maximum Number of GD Circles
The number of GD circles is limited to 16. CPUs that have a GD circle number
greater than 16 cannot be loaded with the global data configuration. However,
STEP 7 does not prevent saving and compiling GD tables with a greater number of
GD circles.
Configuring Hardware and Communication Connections with STEP 7
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