07-23-2020 12:04 PM
I am in the process of transitioning a design from Spartan-6 to Spartan-7. There are a few other posts regarding the migration, but they are very specific questions. Could you give an overview for the general migration process? As of right now I have not changed any of the files since I last ran the build in the old software. There is not currently an accurate pinning schematic referring to the new board, but I was not sure if that would cause an error in the build. For this case, is it just a matter of downloading Vivado, and creating a new project within the new application with the specified Spartan-7 FPGA and generating the bitstream?
I am running into an implementation error, and I believe it has to do with the migration. The build works in the old ISE software, but then I get the following error during the implementation build:
[Place 30-494] The design is empty
Resolution: Check if opt_design has removed all the leaf cells of your design. Check whether you have instantiated and connected all of the top level ports.
Does this error have to do with the .ucf file not having accurate pinning assignments? All of the answers I have read to this error have been relatively vague, with no actionable objectives.
07-23-2020 12:22 PM
If you are running Vivado, you need a xdc constraints file, not a ucf constraints file. xdc has a different, tcl like syntax. You will also need to replace any Spartan6 primitives with Spartan7 primitives.
07-23-2020 12:30 PM
No, it's not because of the pin location constraints. You should be able to implement without constraints and create the constraints file in the implemented design, then rebuild.
It may be migration related, but so many things can happen when porting project that my suggestion is you post it as a failed implementation and provide more details (sometimes the clue of the error is not the error message but some critical warning, etc)
07-30-2020 03:15 AM - edited 07-30-2020 03:17 AM
Good resource for migration is https://www.xilinx.com/support/documentation/sw_manuals/ug429_7Series_Migration.pdf
I hope you find it helpful.