Mb_Client Example 3: Output Image Write Request; Mb_Client Example 4: Coordinating Multiple Requests - Siemens S7-1200 System Manual

12.5.2.6

MB_CLIENT example 3: Output image write request

This example shows a Modbus client request to write the S7-1200 output image.
Network 1: Modbus function 15 - Write S7-1200 output image bits
12.5.2.7

MB_CLIENT example 4: Coordinating multiple requests

You must ensure that each individual Modbus TCP request finishes execution. This
coordination must be provided by your program. The example below shows how the outputs
of the first and second client requests can be used to coordinate execution.
The example shows both clients writing to the same memory area. Also, a returned error is
captured which is optional.
Network 1: Modbus function 3 - Read holding register words
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG
Communication processor and Modbus TCP
12.5 Modbus communication
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