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Recovering from VI_ERROR_CONN_LOST

Question asked by bdot on Jul 15, 2010
Hi,

I am using VEE to communicate over a LAN with an Agilent 34980A for a temperature monitoring application. 

The program works fine, except in those rare occasions where the LAN has temporary outages.

When an outage occurs, the VEE program starts to get VI_ERROR_CONN_LOST messages (as observed with the IO monitor).  This is expected.

However, these messages persist even after the LAN is operational again.  We have used ‘ping’ to verify that the 34980A is reachable.

The only way that we have been able to get the VEE program to communicate with the device successfully (after the network is back up) is to terminate and restart it.  

I’m taking a guess that the communications layers below VEE somehow aren’t able to automatically re-establish device communications after they have been lost.

What do other VEE people do to recover from this kind of temporary LAN outage?

I could certainly write an external monitoring program to detect this situation and explicitly kill and restart VEE, but I’m hoping for something more elegant.  Is there a way in VEE to tell the IO subsystem to restart?

(BTW, I’m using VEE Pro 7.0 and Agilent IO Libraries Suite 15.5.)

Thanks for any suggestions,

Jeff  

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