Description
A write global data operation transfers data to the communication processor of the current node; the data can be transmitted on the network as soon as the node receives the token and then read by all nodes connected to the local network .
A write global data operation is carried out
in one cycle and does not require a master transaction path. To program
an MBP_MSTR block to write global data, use function code 5.
Network Implementation
A write global data operation can be performed only on Modbus Plus networks. The read and write global data operations comprise a Modbus Plus capability known as Peer Cop.
Control Block Usage for Modbus Plus
Register |
Meaning |
|---|---|
CONTROL[1] |
5 = write global data |
CONTROL[2] |
Indicates the error status |
CONTROL[3] |
Number of addresses to be written from state RAM into global data memory (comm processor) (1...32) |
CONTROL[4] |
Reserved |
CONTROL[5] |
If global data is sent via a NOM, enter the NOM module slot in the most significant byte of this register. |