Vivado Vivado is one of our main tools when working with FPGAs. However when implementing for big FPGAs such as Kintex/Virtex Ultrascale devices, the processing can take forever when running with a high resource usage. The goal of this article is to show a way to tackle this problem and generate more bitstreams faster. By launching Vivado multiple times in the Cloud on instances of our choice (need 128 CPUs and 2TB of RAM, go ahead, just kidding, but this…
Questasim When doing HDL simulation Questasim is one of our main tools. However it only runs on Windows and GNU/Linux. Although we mostly use GNU/Linux machines Questasim is not compatible with all distributions. This mainly because of library version compatibility, albeit this being fixable, it is a pain to do (find out which library is the culprit and which version is needed). So creating a Docker image seems like a good solution. It provides a known fixed environment to Questasim…
Going from a single threaded program to a parallel version is often a major pain, this is however often needed to take full advantage of modern multi-core processors. Having to work with threads, locks, and shared data structures is often difficult due to the non deterministic behavior of the scheduler and the difficulty in debugging the complex problems that can happen with multi-threading. It should be noted that several algorithms in the C++ library already have a parallel implementation. If…
Next Friday, March 16th, our University is going to have its annual open day event (if you are close to Yverdon-les-Bains it is a great opportunity to see many interesting projects!). We decided to present an SDR demo: we get a live feed from a professional camera, we use a custom developed encoder, and then we transmit the signal to a receiver, then to a decoder, and finally we display it on a large screen. The whole chain is depicted…
Rationale Generally speaking, building from source offers one key advantage: it is the only way to test the latest features offered by the community. Moreover, if you intend to develop or fix bugs (or even help the community fix bugs), you will need to have a working and up-to-date software environment. All in all, compiling LimeSDR’s software stack is fairly straight forward. It is barely a matter of getting the right cmake options. While we want to compile as many…
One thing that struck us as well as the community is the overall heat that is cumulating on the LimeSDR. Having worked with the Ettus B210, we were surprised of the 60°C shown in LimeSuite under no significant load. Some were concerned by the premature degradation of the board, but heat may also impact RF performances (chapter 4.4). As such, we decided to take action against what we considered could be a problem. This SDR contains three main chips: a Cypress FX3 CPU,…
