hello.

I got the same problem, With normal library as Modbus I can make a RTU comunicacion with s71200. and it works perfectly!

but when I use the other library called MODBUS RTU. It doesnt work,.STATUS 7000.

Anyone has experience with this issue?

Thank you

Best regards. 

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Split from S7-1500 Modbus RTU (comm_load).

Hello Roger,

pls look that you don't have same problem as Osld13, he don't have that MODBUS library in TIA portal, only Modbus(RTU). Simply you know also what I know now, maybe other guys will explain more infos. Everyone had confirm that MODBUS library is functional, Modbus (RTU) not. Simply use that MODBUS library.

hello Duris.

Yeah I know! with s71200 "MODBUS" LIBRARY works..but my goal is to use a ET200SP-CPU as Master Modbus, so If you are using just that CPU ..ONLY AND ONLY will appers one LIBRARY..and it is "MODBUS (RTU)"

Hello Roger,

thnx for this important info. Sry, but I don't have here ET200 system with proper CP card for testing, but your info I try investigate next, thnx again.

Hi,

Have you seen this example?

I suppose is your case...

https://support.industry.siemens.com/cs/document/68202723/master-slave-communication-via-a-cm-ptp-using-the-modbus-rtu-protocol?dti=0&lc=en-BR

bye bye

Hello,

meanwhile we've tested that library and it Works also on S7-1200, some other interesting infos:

https://support.industry.siemens.com/tf/ww/en/posts/147949/