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UDP Read does not receive data

Yes, you are listening on 1121 and 1122. If the device is sending to port 1124, it will not be seen.

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Message 11 of 13
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My problem was in the IP header checksum.

The NIC card is set for 'IPv4 Checksum Offload - Rx & Tx enabled'.  The UDP packets that I was receiving from the PC (LabVIEW) had 0000 for the checksum.  Wireshark indicated that the IP checksum was 'disabled'. Header checksum: 0x0000 [validation disabled]

Of course I assumed this was OK for sending packets back to the PC. And Wireshark reported the same information [validation disabled].

 

When I added the correct checksum to my IP header for packets sent from the DSC, LabVIEW received the packet!

 

NOTE: I am successfully using 0000 for the UDP checksum, but to do that I have to disable the NIC card's 'UDP Checksum Offload (IPv4).

Message 12 of 13
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Thank you for the feedback!

Paolo
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LV 7.1, 2011, 2017, 2019, 2021
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Message 13 of 13
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