Mb_Client Example 2: Multiple Requests With Different Tcp Connections - Siemens S7-1200 System Manual

Hide thumbs Also See for S7-1200:
Table of Contents
Communication processor and Modbus TCP
12.5 Modbus communication
12.5.2.5

MB_CLIENT example 2: Multiple requests with different TCP connections

Modbus client requests can be sent over different connections. To accomplish this, different
instance DBs, IP addresses, and connection IDs must be used.
The port number must be different if the connections are established to the same Modbus
server. If the connections are on different servers, there is no port number restriction.
The example shows both clients writing to the same memory area. Also, a returned error is
captured which is optional.
Network 1:
Modbus function 4 - Read input words (in S7-1200 memory)
Network 2: Modbus function 3 - Read holding register words from a Modbus TCP server
744
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG
Table of Contents
loading

Table of Contents