Hello, 

Just looking if someone could possibly confirm my thoughts on this one. Using the MB_Server function to create a Modbus TCP/IP slave over the profinet port on a S7-1500 allows you to share a Holding Register (4x). I am just looking for confirmation that MB_Sever doesnt allow you to create a Coil Register (0x) also? 

I am thinking the only way to create a Coil Register would be to add in a profitnet to Modbus TCP/IP Gateway? 

Any thoughts on this would be greatly appreciated. 

I have found the solution with the help above. By default the coil and discrete inputs are on the Modbus map are automatically mapped to the PLC's I/O fields, so for example %Q0.0 is the equivalent to bit 1 in the coil register. To change this default setting you need to create your own read coil datablock and specify this under the PLC's System Blocks/Program resources/MB_Sever_DB. Inside that datablock you will see a field called Data_Area_Array which gives you the opportunity to define up to 8 Datablock areas for the Modbus connection. 

How to setup this datablock and settings can be found well documented in the system manual number: A5E37509394-AB , Page 138 onwards. 

I just wanted to say a HUGE THANK YOU ! 

I've resolved my trouble that i struggled with for hours ! 

Thanks X100 !

Can you please upload a sample program with the configurations you made!

I am trying to use input registers and definded MB_DataArea with Data_Area_Array[x] but with no success.