With VHDL being arguably more deterministic and bullet-proof than Verilog, it’s good to see another open source VHDL simulator joining the fray that is not a variation of ghdl. Written by [Óscar Grimal] in C++ with an MIT license, the Pulse project is a still in progress package that provides the entire toolchain, from the compiler to the requisite waveform output.

This waveform output is provided in the form of a text-based user interface (TUI), which at the very least helps a lot with making it cross-platform compatible. As dependencies only a C++20 capable compiler and CMake are indicated.

Of course, with VHDL being a rather hefty language especially once you start piling up the associated standard library, the currently supported language and library features are somewhat limited still so that you’re limited to basic IEEE packages and types, with default values are not supported yet.

Per the roadmap on the GitHub project’s Readme more VHDL language features including generics and additional types will be added, along with an enhanced simulation engine. It’s also said that mixed-language support with Verilog will be added, though SystemVerilog looks to be getting the short end of the stick as usual.

It will definitely be interesting to compare this package to ghdl.

When it comes to building real-world flying vehicles, testing can be arduous and expensive. You have to find somewhere to fly, then you have to contend with environmental conditions and the possibility of damaging your craft if things go wrong. Simulation is a great solution to this, allowing testing without so much risk. To that end, [AlexanderRex] whipped up a platform for testing UAVs from the comfort of your computer desk.

PteroSim is intended as a comprehensive test bench for simulating autonomous aerial vehicles. It can run PX4, ArduPilot, and Betaflight binaries right in the simulator. The autopilot code is given simulated sensor data, and in turn responds with actuator commands, just as it would in a real craft. The simulator runs the flight dynamics using JSBSim, and the resulting scene is rendered in Unreal Engine 5.

If you’ve ever wanted to quickly road test different autopilot settings without heading out to the field or risking hardware, this is a great way to do so. It’s hard to beat the speed of iteration that is possible when testing on the computer on your desk. We’ve featured similar work before, too.