Context
For a reason X or Y, depending on the needs of the user, it sometimes happens that we want to make use of information in the program which is only available on the explicit language objects associated with a business function (For Modbus example) of the BMXNOM0200 communication module. This information is very often intended to be displayed in an HMI or a supervision or even according to its value triggered certain actions in the user program.
As the saying goes, a sketch is worth a thousand words: below is a table showing explicit exchange objects for Modbus master or slave communication of a BMXNOM0200 module.
Below, in explicit exchange the step-by-step procedure for reading the %MWr.m.c.5 language object relating to the number of responses received with a CRC error:
A.First choose Topological as the I/O data type, when adding the BMXNOM0200.2 module to the rack
B. From the CE variables editor, create an IODDT variable of the T_COM_MB_BMX type with the address %CHr.m.c (r=rack on which the BMXNOM0200 module is installed, m=the slot of the module on the rack, c=module communication channel number).
C. Executed the EF (Elementary Function) READ_STS with the IODDT type variable created previously as input
D. From the variable’s editor, initialize the animation table or a new animation table with %MWr.m.c.5.
Note 1 : it is possible to obtain the information from the debug tab of the BMXNOM0200 module in online mode.
Note 2 : When adding the BMXNOM0200 module to the rack, if Device DDT has been chosen as the I/O data type then in this case the READ_STS_MX EFB must be used instead of READ_STS
Product Line
BMXNOM0200, M580 Standalone, M340
Environment
Windows Pro 10, EcoStruxure Control Expert V15.2
