Communication error when trying to run FPGA VI

[jbailey]

Whenever I run a certain FPGA VI I get an error saying:

An error was detected in the communication between the host computer and the FPGA target

If you are using any external clocks, make sure they are connected and within the supported specifications.  Also, verify that the rate of any external clocks match the specified clock rates.  If you are generating your clocks internally, please contact National Instruments Technical Support.

This VI has run fine in the past and I am not sure what has caused this change.  I can run other FPGA VI's in my LabVIEW project without any problem.  The VI does not make use of any external clocks as far as I know, though I am a little unclear by what would be considered an external clock.  This particular VI monitors an Analog Input and controls two motors with PID control through two Analog Outputs.

I am not sure what other information is required to further describe this problem, so please let me know if I have left anything out.  I am running LabVIEW 8.5 on Windows XP SP3.

[Smootastic]

Hi jbailey,

What version of NI-RIO are you using?  Does copying the code to a new VI cause the same issue?

[jbailey]

I have NI-RIO 3.2.1.  I am going to try and create a copy of the VI and compile it and see if that produces the same error.

[jbailey]

I saved a copy of the VI in question with a new name and changed one constant value in it to make sure it would recompile the whole thing.  The new version of the VI runs without any problem and the original still gives the same communication error.

[jbailey]

This has at least given me the ability to move ahead with my work but I would still like to figure out why I have this problem with that specific VI.