Modicon/Schneider Electric are the founders of Modbus and Modbus/TCP. However in our software we limit the users in functionality. All years I'm with the company, this questions pops-up regularly:
Why does Schneider NOT support the use of other Modbus function codes than 3, 16 and 23 in IO-scanning?
Other function codes can be implemented (read of %IW/3xxxx references) using DATA-EXCH functions, which is a lot of programming effort and introduces limitations, IO-scanning doesn't have.
Today I got a question (again) from one of our alliance partners: Why does Schneider not support other Modbus function codes than 3,16 and 23 while competitors like Mitsubishi, Phoenix Contact and WAGO offer this functionality by default?
Can't the Modbus Device DTM be enhanced to offer this functionality?