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It would be nice if this code:

Case Structure versionCase Structure version

 

could be replaced by this code:

Select versionSelect version

 

but doing so gives an edit-time error specifying that "Select: Possiblity of Dynamic Refnum not supported for current target".

 

Is there a fundamental reason this can't be allowed? The behaviour is presumably the same in each case, and the references are from the same place in both cases. In the case structure, the exact same references that are passed to the Select node are used, with the same True/False choice.

 

It's not a huge issue, but it would be a nice usability/readability improvement.

If you try to compile while pointed to a Compile Server that is for any reason inaccessible (server is down, firewall, typo in the hostname, etc.) you must wait through the generation of intermediate files, then you receive the error message that LabVIEW FPGA was unable to contact the Compile Server at your configured hostname/IP.  Generating intermediate files can be a lengthy process and it shouldn't be necessary to wait through it just to find out if you have configured your Compile Server correctly.  Any of the following would be a much better experience:

 

  1. Attempt to connect to the Compile Server before generating intermediate files.
  2. If the connection to the Compile Server fails after generating intermediate files, give the option of specifying a new Compile Server hostname/IP and retrying without having to re-generate the intermediate files.
  3. At least put a connection check in Tools >> FPGA Module Options... so the user can test the connection to the Compile Server.  You wouldn't do this all of the time, but if you run into a problem at least this way you can keep trying new configurations without generating intermediate files.  Right now the best way to test new configurations is to create a blank FPGA VI (to decrease the length of generating intermediate files) and keep trying to compile it.

Proper unit testing is a key component of large LVFPGA project success.  As the number of modules grows, so does the number of units tests increase.  We are working on automatic continuous integration methods that will continue to monitor the accuracy of all modules and assemblies throughout the project life cycle.  IP Integration node and NI's wrapper around Xilinx IP makes this task more difficult.  When our continuous integration machine refreshes the source code from the repository it has to regenerate these nodes in order to compile.  The "Regenerate IP Integration Node Support Files..." tool does not always properly update all IP.  It seems like the NI wrappers around Xilinx IP are most problematic.  The only way a computer can properly update its version of the node is to open the VI and click through the Xilinx IP generation pages to get it to update.

 

As a rule we do not commit build products into our source code repository.  One option would be to submit all the support files generated when first creating the IP integration node so that others users might not have to update.  This can become messy and quickly unwielding.  The problem arrises when changes to the IP integration node cause more or fewer support files to be generated.  This then requires deleting some files from the repository and adding others which is tedious and leads to errors.  One compromise would be if the IP integration created one single compact file that contains all the information needed (expect the input vhd, etc. files) that could be committed to the repository.  Even better would be to roll this information into the VI itself.  Neither of these might be ideal if the support file contents take up a lot of disk space.

 

Regardless there needs to be a better solution to allow for automated continuous integration testing.

I like rearranging my BD items manually and FPGA items behave weird.

 

If I shift a normal Property node left or right, the "latch point" of the wire is shown below.  For some reason FPGA nodes latch differently and leads to some ugly wiring.

 

FPGA property node latch point.png

 

It's only cosmetic, but please change it....

 

Shane.

Typical Xilinx IP core icon like FFT and DDS looks like this - in expanded mode:

Typical Xilinx IP icons in expanded view

The connector labels are very hard to read. I guess everybody agrees on that this could be improved. And it is not that there is a "standard" narrow width to obey, for instance FIFO is wider than the Xilinx IP icons.

Thanks for considering this.

I am currently running into this issue where I have some constant data I'm trying to write to some DO lines. I want this data to be a constant array on my block diagram, so I create the array programmatically under the "my computer" target. I then change the indicator that is populated to a constant and move it to the FPGA. When I right click and set the array to be a fixed size, it replaces all my data with 0's. I propose the data should not be cleared if I set my fixed array size to be equal to the size which the array already is.

I've searched but can't see anything similar - please add a method for setting the timeout for FPGA nodes. This includes the 'Open FPGA reference' and FPGA IO nodes.

 

If you disconnect a cRIO FPGA (e.g. NI 9148) from the network, it takes 20-30s for the IO node or Open FPGA reference to execute. This is really bad for the user experience as if they try to exit their application in this time it may take half a minute for the application to exit. It also means you may have to wait that length of time to realise that your FPGA has disconnected under most use cases (you can obviously have an external watchdog loop to check that the node is executing in a timely manner)

 

Please allow me to configure the timeouts for these nodes similar to the TCP/UDP or VISA nodes. They are very similar in how they operate to the FPGA nodes (i.e. a hardware device driver which is susceptible to disconnects!) so I don't understand why these have been omitted.

 

I wouldn't mind having to set the timeout as part of opening the FPGA reference and then internally have it use the same timeout for other IO nodes as follows:

2014-09-29_17-16-29.jpg

 

 

Sometimes I just want to compile a lot of Bitfiles (Be it for a release or a debugging test case) and I have to right click each and every Build spec and choose "Build".  then wait about 10 seconds and do the same again for the next build spec.

 

How about being able to select multiple build specs and then select "Build Selection" and have time to go for lunch while the PC queues up all the compilations?

 

I don't use a compile farm and everything is done locally but at least the queuing could be automated.

 

Shane.

I have recently started placing wire labels in my code to keep track of datatypes of wires flowing around my code.  This is very useful to understand what is going on on the FPGA since not all grey wires (FXP) are equal and slight mismatches can mean big trouble in the code.

 

As such I tend to label wires like "Phase FXP+25,0" and so on.

 

What I'd love to be able to do is to place a formatter in a Wire Label to be able to keep such labels up to date because at the moment it's probably more error prone than anything else due to some wires and labels not being synced any more due to code changes or bugfixes.

 

If I can set a wire label to "Phase %s" or similar to place the ACTUAL datatype in the label this would be amazing.

I have been working with FPGA for quite a while, and realized that manually opening and editing DMA, Target Scoped, P2P, VI scoped Memories, and project scoped memories can be very tedious and time consuming.  Wouldn't it be great if there was a way to edit FPGA FIFOs and Memories from a single place.  This notion gave birth to the FPGA FIFO Editor and FPGA Memory Editor.  These editors would give the ability to see, create, remove, and edit FIFOs or Memories for that specific project (list both project and VI scoped items).  Furthermore, their could be some additional logic built into the Editor that would alert the user when they have tried to configure something incorrectly (for instance an R Series target only has 3 DMA FIFOs, alert the user when they have configured more than that).

 

Listed below is  a mock-up of the FPGA FIFO Editor.

 

FIFO Editor.png

Arising from similar requirements as I have posted many moons ago: HERE.... I naively thought putting a terminal in a disable structure would remove it from the FPGA compile. It doesn't.

 

Years later, I have developed a nice debug interface for my FPGA code which is becoming more and more modular as I refactor it.  I have many sub-modules with their own debug interfaces which can be turned on or off from the top-level VI via LVOOP method injection.

 

The problem is that I can't really compile my entire FPGA VI with ALL debug paths enabled as this just won't fit (It will sometimes compile, but most often not and our FPGA code base is still growing).  And this is before I even think about making my debug information more detailed.  I would like to be able to easily switch certain aspects of the debug interface on and off as testing requirements change.  On the debug interface level I can do this easily by simply not reading the data from the objects being used for the data transfer or simply passing in abstract methods which don't actually do anything and get optimised away.  But I'm left with a load of FP controls which are still eating up resources on the FPGA target. Smiley Mad I don't want to delete the controls because that leads me to X copies of ever-so-slightly out-of-sync versions of my test VI which quickly becomes a maintenance nightmare.  Instead, I want to be able to "easily" reconfigure my test front-panel to only compile the stuff I'm currently actually interested in.

 

Part of what I would like is the ability to actually define areas of the FP which are enabled, disabled or enabled (and preferably also based on whether simulation is active or not - hence conditional disables for FP).  This way, when compiling, the FP elements will actually disappear and full resource savings can be made (as Xilinx is clever enough to optimise away any pointless code LV may stillhave instantiated in VHDL).  In addition, the ability to define certain controls as being enabled only when in simulation mode can allow us to have SGL graphs and so on present when needed during debugging.

 

So, would having conditional disable options for the FP (where controls are shown as greyed out when not available) be of interest to anyone?  If this would be an FPGA only thing, I wouldn't shed and tears.

 

Am I the only one who would use this? hmm. Maybe.

In a FPGA code, when you click in a function (Math, Array or Comparison) to create the first constant, control or indicator, like in an Add function, it's created as a Double (DBL) type, which is not suitable for this target. In this case, it will be better if the data are created as a Fixed Point (FXP). In other cases, like in Array functions, an Integer (I32) may be a better option. One thing is for sure: Should not be a Double!

My original problem was that I in the FPGA have an array of data, where I need to do some calculation, where the only appropriate way was to use a pipeline. The pipeline is a very strong tool in the FPGA, but I think the LabVIEW tools could be changed so the pipeline is easier.

 

My old implementation if the pipeline:

old pipeline.jpg

 

Suggested implementation of single cycle pipeline, with shift registers in the tunnels, so all the code is run on each of the 5 elements in the array.

New pipeline.jpg

Maybe there should be added a number of iterations (like the “for loop”), if the number of data, is not defined by the array size.

In another project I have a continuous running pipeline, I have implemented in different ways, but one simple is as shown:

 

Before

 

old pipeline2.jpg

 

 

Here the new pipeline sequence could also be used, maybe like following:  

 

New pipeline2.jpg

 

Here it should be stated in the loop tunnel, that the input data is read continuous.

Here I have shown in both examples, that it should be single cycle times loops, but maybe the pipeline structure should also be able to run with another timing (determined by the slowest frame).

I have seen the idea about the timed frame, it will help on the last example, but there will still be need for a pipeline structure.

I don't like static resource definitions FIFOs, Block RAMs or DMAs in my projects.  I prefer to have the code declare such entities as they are required because this makes scalability much easier to achieve.

For FIFOs, BlockRAM and so this is no problem, but there are two things we currently cannot instantiate in code:

DMA Channels

Derived clocks

 

To deal with the seond option: Why is it currently not possible to create a derived clock in code.  The ability to automatically have one piece of code accept a single clock reference and let one loop run at a multiple of the speed is something I've wanted to be able to do in the past but it is currently impossible in LabVIEW.

 

Please let us configure / define derived clocks in LV code.

With LVFPGA I work almost exclusively with fixed point numbers, and having to convert my numbers to 8 bits or 16 bits just to use the scale by power of 2 function isn't convienient.

 

17949iDCF3B4A5081C518C

With even simple examples we experience errors when trying to run Instruction Framework based LabVIEW FPGA VIs.

 

This is a blocker for our using Instruction Framework.

MGT interfacing to the 7915 is provided: https://forums.ni.com/t5/Examples-and-IP-for-Software/Aurora-64b-66b-Streaming-Example-for-the-PXIe-7915-Ultrascale/ta-p/3952187

 

It is not provided for other cards such as the 5785.  Is the interfacing the same?  Could examples for this be provided?

One of the benefits of the Instruction Framework is that one could develop several modules each using Instruction Framework.  The modules can then be integrated and the Instruction Framework modules can be assembled using Collections.

 

This information is not clear and the provided tutorial does not provide information on this use case.

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.

 

Better visual indication of estimated and final timings in compilation report.

 

Would it be possible to add some visual clues as to whether a given clock in an FPGA design has been met or not? Maybe a background colour, green for good and red for bad?

 

color clocks.png

Sometimes it's really hard working out which clocks have met timing and which not.