LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Modbus not working with LabView7 Runtime

I have recently upgraded to LabView7 and have an application that comm. with a ModBus Controller. Works fine in LabView 6 and using runtime 6. Works on my development computer using 7. On the same computer that it works fine using runtime 6 it won't run using runtime 7. Any Ideas?
0 Kudos
Message 1 of 9
(3,612 Views)

Did you rebuild the executable using LV7?

Khalid


0 Kudos
Message 2 of 9
(3,612 Views)
Are you using serial VISA ?
if so, you have to install the VISA run time engine, or when you build the executable (application builder) enable the selection for serial port support.
0 Kudos
Message 3 of 9
(3,612 Views)
Yes, I did rebuild the executable.
0 Kudos
Message 4 of 9
(3,612 Views)
I am using serial visa as well as GPIB VISA.
The GPIB VISA that I execute before the MODBUS works fine. I did rebuild and distribute with serial support selected. I get a null node at the execution point for the MODBUS code only in the 7 runtime environment.
0 Kudos
Message 5 of 9
(3,612 Views)
Hello,

I have two questions for you:

-What ModBus VI's are you using? Who wrote them?
-What is the exact error that you receive at runtime while executing on the LabVIEW Runtime Engine Target?

This sounds like it's an issue of the ModBus VI's depending on something else that the Runtime Engine isn't providing.

Scott B.
Applications Engineer
National Instruments
0 Kudos
Message 6 of 9
(3,612 Views)
I am using some code called modbusmaster.vi. It was on another machine when I started here so I am not sure of it's source. It uses simple visa commands to communicate. I attached a file of the pop up error that I get.

Sorry that I could not get back on this. The system was being used in 6.1 so I could not run it to copy the error message.
0 Kudos
Message 7 of 9
(3,612 Views)
Here is a little twist. I usually do not show my subVi's when running. I did a little more troubleshooting and changed this subVi to show when called and it works fine. Any Ideas?
0 Kudos
Message 8 of 9
(3,612 Views)
Hi,

I looked into this issue and here's what I found.

Null Window Error when Running Application Built with Sub-VI?

I hope this helps.

Feroz
National Instruments
0 Kudos
Message 9 of 9
(3,612 Views)