CP341 is used as Modbus RTU Master in a CPU414-4H system. I have downloaded the driver as per H-system requirement. Also dongle is installed in the module. Modbus communication parameters are set as per slave requirement: Baudrate 1200, Stop bit 2, No parity, two wire RS485 connection scheme.
I have used program segments from "8106__36_220609.zip" which i downloaded from another thread. Once request bit is started, i can physically see Tx and Rx leds blinking in CP341 module; but status error "08 30H" is continuously evaluated for all the slave nodes. The same error is also logged in the online diagnosis of CP341. No data is received in destination DB. FB7, FB8 are used for send and receive function. Function code 3 is used and LEN parameter 6 is set as mentioned in CP341 manual.
Looking for advice on the issue. Any particular HW/SW/FB requirement to be fulfilled?

Thank you Daniel for your clarification.
I have used transmission rate, number of data bits, parity, number of stop bits as per partnered link. however I need one more clarification. 
I have not installed resistor at start and finish end of the multidrop configuration. Is it possible that error '08 30H' (Check if transmission line is interrupted) is generated due to mismatch of signal transmission in absence of resistor?
I had placed order for resistance of 330 ohm (as found in the manual). Is this rating ok?
I have not used FB7, FB8 before for Modbus send and receive fucntions. Are they ok/reliable for data read/wirte in CPU414-4H redundant system?

with regards
Annoy

Dear Annoy

First you need to install the Terminating Resistors ( as prescribed ) for Communication Interruption.

Also FB7 and FB8 normally used for Modbus Communication with CP341