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Having recently attempted to get started with Simulation for debugging my FPGA code I found out that apparently the built-in LV support for native LV testbenches using simulated FPGA is supported only for ModelSim SE.
This is a shame since ISim is included with the FPGA toolkit.
If feasible, expanding the functionality to allos co-simulation with ISim would be a rather splendid idea ideed!
Shane.
I've developed a small test utility for testing FPGA code on my windows machine before proper FPGA testing and have noticed something I think could be improved.
If I have a graph or any other indicator with DBL default data type within a conditional disable, the compiler still throws an error regarding an unknown state (DBL). Although the terminal is in the diagram disable, the object seems to remain on the FP (but also in the code being sent to the FPGA compiler).
Can we actually remove the graph (or other culprit control) in the background before starting the actual compile so that I don't need to drop and re-connect every time I want to switch execution systems?
Shane.
I have to remember to place a comment next to every memory element so that I can quickly know its size. This is especially important because I can't get to the property window if I'm viewing the vi outside of the FPGA Target Scope. I can view the data type of a memory/FIFO element by hovering over the wire that goes into a read/write property with the context help window open, so I don't really care about that. However I cannot view its size. This could be fixed in one of two ways, add it to the context help when you hover over the element or display it directly on the memory element.
Presently, the Xilinx Compile Tools do not appear in the MAX technical report or NI License Manager. As a result, to determine the version, users must go to Add/Remove Programs in the control panel to determine which versions they have installed. It would be great for troubleshooting if the Xilinx Version could be implemented into the MAX technical report.
In addition, the Compile Worker states that the version of Xilinx used is 12.4, regardless of whether you are using 12.4 or 12.4 SP1. It would be useful for the compile worker to note which version it is using. Specifically, often the compilation chooses the compile tools based on what it was compiled with previously. When upgrading to 12.4 SP1, the user may think the compiler automatically uses the new compile tools and has no visual cue to verify the compile tools version used.
I know its not necessarily a LVFPGA issue, but its us LVFPGA users that use fixed point numbers most often. Why don't fixed point numbers always show coercion dots. If every unnecessary numerical digit wastes chip resources, then isn't it more important that we know about these coercions so that we can avoid them?
At present, if you are trying to simulate your FPGA's actual logic, using a custom VI like this:
Then you know that your custom VI test bench only has one case for methods (just a general method case, not a case for each method available). There are ways to get around this problem--for example, this example emulates a node and suggests using a different timeout value for wait on rising edge, wait on falling edge, etc, but one still has to write the code for the different methods.
My suggestion is as simple as this: make test benches easier to use by handling all of the methods and properties with a set behavior. That way, all one has to set up when creating a test bench is the input and output on each I/O read/write line. At the very least, it would be nice to have the ability to read what method is being called, so the appropriate code can be set up without complicated case structures.
When you configure Memory in LV FPGA, there is no way to find specific references to particular memory blocks using the search function. The search will show "ALL" memory access nodes, not just the ones you are looking for. Additionally a text serach will not catch the text from the X Nodes. This can be particularly tedious if you have many nodes in your hierarchy and are looking to only see references to a particular memory block.
I would like to see the search improved to allow filtering of the memory nodes the same way that we can search for global variables (find definition and find references)
Hello,
i would suggest some Improvements to the Timing Violations Window.
With kind regards
westgate
When working with LabVIEW FPGA if so much as the value of a block diagram constant is changed, the entire application must be recompiled.
It seems that there could be a smarter method to deal with recompiling that might allow selected portions of the block diagram to be recompiled without the need to recompile the entire app.
Some of the tradeoffs might be lower FPGA utilization efficency and timing constraints, but allowing minor changes to the FPGA code without the overhead of a complete recompile would certainly make debugging applications much faster.
I am not necessarily proposing an implementation just posting an idea that seems like it would add value to the LV-FPGA development experience.
Memory initialization is one of the more tedious aspects of LVFPGA coding. A lot of my LVFPGA vis have multiple memory elements that I need to access simultaneously for a given operation. I've tried to streamline the initialization process by making all memory initialization vis read from an init values file and populate the array indicator. However now I have to have multiple initialization vis reading from different points in the same init values file. If I could somehow get a parameter into the memory initialization vi, I could programmatically select from where in the init values file to read. Here is how this could work:
I do a lot of debugging by simply running my LVFPGA code in traditional labview test benches. Its kind of a pain to have to open up an FPGA scoped version of my vis just to configure the memory elements or just to view the length/data types.
I would like to see some form of simple locking mechanism for VIs that are targeted to an FPGA.
The use case would be where you have compiled a VI for your FPGA target and are currently in the process of debugging/testing it. While running interactively and opening and closing VIs, you accidentally move something on a block diagram without realizing it. The next time you hit the run button LV shows you the "Generating Intermediate Files" dialog and you have now ventured down the one way street to a full FPGA recompile.
I know that source code control or setting all files to read only would also work, but when debugging a project, it is cumbersome to continually check all files in and out, or to continually change the directory attributes.
Just a simple lock/unlock button on the toolbar to keep from shooting myself in the foot while debugging.
....posted as I sit here waiting on a 4 hour FPGA compile for just this reason.
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