02-03-2018 01:30 PM
I took a design in Vivado 2017.4 and opened the implemented design and made a couple of changes where I took an OBUF and disconnected it's net and reconnected the OBUF input to <const0>. My question is that now that I made the change, how to I make it applied to the design where it gets placed and routed so I can update the bitstream? Interestingly after I make the change nothing shows out of date.
02-03-2018 02:12 PM
02-03-2018 01:58 PM
Since you refer to the design as "implemented", I assume you are in project mode.
When you open an implemented design, you are essentially loading a copy of the design into memory. From there you can view it, and experiment with it, but from this point, there is no way to put any changes you make back into the project. The implemented design is the end goal of the project flow.
So the answer is you cannot put it back into the project.
However, what you do have is a design that is in memory. The only way to proceed from this point forward is essentially in non-project mode. You can manipulate the design, even making ECO changes (which is what you describe), which modifies the design currently in memory. From there, though, everything you do must be done through the non-project flow. If you have changed connectivity and now need to route the nets that have changed, you use the "route_design" command. If you want to "save" the design (and it is important to realize that this saving is no longer part of the "project") you can do a write_checkpoint to save a dcp file of your modified design (outside the project, so preferably outside the project directory). If you want to generate a bitstream, of the design, you can do the write_bitstream command.
But, as I said, all of this is outside the project flow. The design you are working with is no longer part of your project. It is for this reason that the project never indicates it is "out of date" - the implementation run was run, and none of the dependents of the run have changed, so nothing is out of date.
02-03-2018 02:12 PM