From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, ni.com will undergo system upgrades that may result in temporary service interruption.

We appreciate your patience as we improve our online experience.

FieldPoint Family

cancel
Showing results for 
Search instead for 
Did you mean: 

OPC Field Point Item->Write intermittent failure

I'm using OPC to control some FieldPoint blocks FP1601 & FP-DO-403. Sometimes during startup of my application (VC++) I get failures on Item->Write. A COM error is caught ( -2147188341). I can't find a associated definition (spOPCServer->GetErrorString throws when I pass this error in)

Item is defined as a OPCAutomation::OPCItemPtr.

Again, this happens intermittently during startup and I often can re-send the command and it succeeds after a few retries. And, once successful, the point seems to work fine...

0 Kudos
Message 1 of 2
(2,867 Views)

Hi Rcsj01-

Are you resetting the controller at startup?  It may be possible that the controller is still booting and is only ready to target after a few failed attempts.  The fact that you're able to eventually receive valid data seems to point to this being the cause of the error you're seeing.  I would just monitor for that error and only continue once a successful write is made.

Hopefully this helps-

Tom W
National Instruments
0 Kudos
Message 2 of 2
(2,850 Views)