Using Dual Ethernet on cRIO (Modbus and Web Server)

[IvanRebollo]

Hello everybody,

I´m developing an application with a cRIO 9022 for acquiring data and I want to communicate with the Modbus TCP protocol to a SCADA across Ethernet port 2. But sometimes I want to be able to monitoring waveforms trough a web server on the Ethernet port 1. My configuration is the next:

Port 1

IP= 10.4.4 68

Port 2

IP=200.4.7.152

 I have already configured the Modbus slave option on my cRIO and I try it with a master on the port 2 with a scan rate of 10 seconds.  Independently, I have already checked the web server with my computer with the IP of the Port 1.

The problem is when I try to access to the web server on my computer when the other device (Master Modbus) is polling the Port 2. My cRIO 9022 is stuck like waiting for a network response.

Repeat, when I try the both communications (Modbus, web server) on a separate way they work fine, but when I try to do both things at the same time, my cRIO crashes.

Thanks for your time

[MoviJOHN]

A very likely cause for this is that you are starving for cycles in the cRIO by not having delays in your loops.  Try adding a 1ms delay, or maybe a little more, and see if it helps.

[IvanRebollo]

HI MoviJOHN

Thanks for your response but my code already had a delay on the state machine loops.
It seems like there´s an issue with the network speed (intranet) at my office and the cRIO reached the timeout for the web server conection. I tried conecting the cRIO directly to my computer (not trough the intranet) and it works perfectly.

Regards!