"LabVIEW FPGA: The compilation failed due to timing violations, but there is no path information because the timing violations are not of type PERIOD

Question

The compilation of my labview fpga vi fails with the error message "LabVIEW FPGA:  The compilation failed due to timing violations, but there is no path information because the timing violations are not of type PERIOD".
In the 'final timing (place and route)' report, the requested frequencies are all below the maximum frequencies and the compilation error message is only displayed at the very end on the 'summary' page.
I tried to optimize my labview fpga vi with pipelining, but had no success.
Can anybody offer some advice on how to debug fpga code with this error? Is this really a timing error or something else?
Software:
Labview 2011, fpga 2011, xilinx tools 12.4 sp1
Hardware:
NI PXIe-1071 Chassis
NI PXIe-8108 Embedded controller
NI PXIe-7965R FPGA FlexRIO FPGA module
NI 5761 250 MS/s 14 bit Analog input digitizer
The Xilinx log of the compilation run is attached.
Also, this issue was already discussed in this thread ~6 months ago, but no satisfying answer was offered so far...
Thanks,
Fabrizio
Attachments:
xilinxlogc.txt ‏2313 KB

Answer 1

Hi Kyle,
the problem is: I have one computer which compiles the VI successfully and a second one which shows that error. Both use the same software setup (LV2011SP1+RT+FPGA from DS2012-01). Both use the same project file - atleast SVN shows no difference.
- You can have one FPGA VI where one computer is compiling successful and a second one complains. (Btw. I have a SRQ running in Germany on this topic.)
- More problems: After successful compiling on first computer and transferring all to second computer (using SVN, including the full project folder with all files like bitfiles, lvproj, and everything) the second computer is unable to start the RT executable due to error "FPGA VI needs to recompile". Solution so far: Call the FPGA-OpenReference with the bitfile instead of the VI (as I used to do until now)...
- More problems: After modifying the FPGA-OpenReference to use the bitfile (on the 2nd computer) and transferring all the files back to the 1st computer (using SVN as before, including the whole project) the 1st computer complains: FPGA-OpenReference is creating a different reference than is used in the VI. So what happens here? On one computer my VI is ok, the reference is typed correctly. Transferring all the files to a different computer the VI isn't ok anymore due to changes of the reference??? You know: all files are the same: lvproj, FPGA bitfile didn't change, cRIO reference didn't change...
All those problems didn't occur on my RT-FPGA projects in LV2010SP1. I'm not pleased...
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome