NI cRIO-9871 serial communication problems

I'm using NI cRIO-9871 RS485/RS422 Serial Interface Module with NI cRIO-9064 integrated controller and chassis to communice with Modbus power meter.

While testing the communication I am not able to read data from the meter. It appears there are some issues with serial communication.

 

To find the issue I have checked several points.

 

1. According to NI C Series Module Compatibility Chart cRIO-9871 is supported in FPGA and Scan mode, for all cRIO platforms. 

So there are no any compatibility issues.

2. I have tested the module with the provided example for FPGA (NI-987x Serial Loopback). While testing it was not giving any errors while writing data, but was not reading sent data.

 

3. I have tested the module in Scan mode with example provided for the serial communication (Simple Serial.vi). It was writing successfully, but was giving Timeout error while reading.

 

4. I have tried also to test data transmission with MAX Visa Test Panel. And again it was writing data without errors, but while reading it was giving Timeout error.

 

Please, let me know what can be the reason of serial communication problems.

 

Thanks,

Arev