Author Topic: ModbusTCPCom1 Unknown error code -34  (Read 822 times)

scott.clark

  • Jr. Member
  • **
  • Posts: 96
    • View Profile
ModbusTCPCom1 Unknown error code -34
« on: April 08, 2021, 12:14:15 PM »
I am receiving this

Archie

  • Administrator
  • Hero Member
  • *****
  • Posts: 5268
    • View Profile
    • AdvancedHMI
Re: ModbusTCPCom1 Unknown error code -34
« Reply #1 on: April 08, 2021, 12:18:43 PM »
The -34 is typically a "could not connect" error in the ethernet drivers.

scott.clark

  • Jr. Member
  • **
  • Posts: 96
    • View Profile
Re: ModbusTCPCom1 Unknown error code -34
« Reply #2 on: April 08, 2021, 05:34:14 PM »
That is interesting.  I will test more on some different machines and see if the same connection issues exist.  Maybe it is my development PC.

Thank You!


scott.clark

  • Jr. Member
  • **
  • Posts: 96
    • View Profile
Re: ModbusTCPCom1 Unknown error code -34
« Reply #3 on: April 14, 2021, 05:26:47 PM »
The cause of the -34 was an unreliable USB - Ethernet adapter.  It would drop in and out of connection.  When I switched over to the built in ethernet port on the PC, I never saw the issue again.   Confirmed the adapter issue by using the command prompt and issuing ping command with -t option.

Thanks