Hello everyone.

I need to read/write data from S7-1200 to Bosch rexroth fvc5610 frequency drive.

I have no errors in status of MB_Master block. But in the mode of reading (mode=0)  I read only  zeros. What it could be?  Using osciloscop I see that some data transmission is present but I don't know if VFC is answers to PLC. I also make delays between requests for 300ms to exclude any overloads - make only one request.

I use modbus blocks from folder library with modbus (not modbus RTU). Could be problem in it?

Does any body has such problem?

I use 

- CB1241 - for modbus

- S7-1200 PLC 6ES7 214-1AG40-0XB0

- Bosch rexroth VFC5610

-TIA Portal v14 (without updates)

- terminal resistors for mosbus line.

Modbus configs of plc

9600 b/s, no parity bit, 8 bit transmission, 1 stop bit

Modbus configs of VFC:

9600 b/s, no parity, 1 start bit, 8 bit transmission, 1 stop bit, no parity

Here is in txt file I included program.

If I change modbus blocks to modbus TRU then I get error 8281. Changing doesn't help.

Yes, I currently solved my problem.

Problem was very easy - i make addressing in decimal system, but need to make in hex. After taking it to notice, problem was solved.

Hi 

I have the same problem, 

Can you post a code snippet where you manage to read and write values ​​to the device?