wokwi-features VS QEMU

Do you know https://wokwi.com/ ? I have found support for the -C3, and even Rust development. Although it's online, if you are looking for local stuff I don't know if what they use is available, or if it's a secret sauce.

Even you can learn MicroPython using online simulator using WokWi. You will find tons of ready projects of others that will help you to learn.

The primary goal of Simplified Embedded Rust is to make embedded Rust accessible and straightforward. By lowering the barrier to entry, the book aims to increase accessibility and provide a coherent overview of embedded Rust, minimizing the challenges many of us faced early on. The book gradually builds up the necessary knowledge, making it easier for readers to grasp more complex concepts. Practical material for each peripheral is included, allowing readers to apply their learning effectively without needing physical hardware. Thanks to modern tools like Wokwi we can replicate the software learning experience in embedded more effectively. The book also supports programming any supported ESP device in Rust, leveraging the powerful Espressif crates.

No, no - I have a half a dozen RPi's of varying revisions. Since they run Linux and the SDcards are less than robust, anytime you accidentially trip the power (which to me happens several times during hardware debugging sessions) you risk scrambling the rootfs and thus need to reflash a new SDcard. Some SDcards get damaged.

I recommend using Arduino and/or Wokwi (https://wokwi.com/) to get started.

More Wokwi Integration: Wokwi is an amazing embedded simulator and is great for getting started quickly. For a learner, there's no need for toolchain setup or even the purchase of hardware. There are many features as well that make it quite a flexible tool supporting a lot of features right from the browser. Users can also vote for more features. Still maybe at some point, one might want to tinker with physical hardware. However, at that point, they would have gained some confidence first. Currently, only ESP boards are supported with Rust on Wokwi. I hope for the variety to expand soon.

In addition to the other great suggestions here I wanted to point out that you can practice and learn a lot for free using an online simulator such as wokwi.com and tinkercad.com (among others)! And you don't have to buy an Arduino or any parts to get started!

And you can prototype all of this first to get it working for free using an online simulator at sites like wokwi.com or tinkercad.com!

If you don't have the budget for real hardware consider the simulator at https://wokwi.com/ It works with Rust (at least for ESP32, haven't tried other architectures). Bonus: you can't blow up the electronics by a wiring mistake.

There are several choices for running code in partial or full isolation. Some languages include lightweight environments that do not interfere with each other, e.g., virtual environments in Python. However, due to caching and links, these are not sufficiently isolated for us. At the other end of the spectrum, we can run code in a node of a cloud computing service. However, the overhead and cost make this not worthwhile given our needs: isolation, but not very strong security requirements. Alternatively, we can run a virtual machine or emulator such as QEMU, VirtualBox, or others. This also has too much overhead given our needs.

Over the last year I have been rewriting QEMU's x86 decoder. I am now at a point where it should not be too hard to add APX support.

My decoder is mostly based on the tables in the manual, and the code is mostly okay—not too much indentation and phases mostly easy to separate/identify. Nevertheless there are several cases in which the manual is wrong or doesn't say the whole story.

The top comment explains a bit what's going on: https://github.com/qemu/qemu/blob/59084feb256c617063e0dbe7e6...

QEMU is an excellent open-source project that enables users to work on various projects across multiple platforms. Starting a VM instance with QEMU is straightforward. On my old Intel-based Mac, the following command will launch an Ubuntu cloud image:

Another important tool from the same organization is Vagrant, which provides extra help in running VMs built with Packer. Of course, the choice of a VM provider is also very important, as some VM providers may not be supported on certain platforms. For example, there are no VMware or VirtualBox releases that support Apple Silicon. However, QEMU is supported on most platforms, including Apple Silicon, which is why this provider was chosen here.

My most-wanted QEMU feature: https://github.com/qemu/qemu/commit/a2260983c6553

Using `gic-version=3` on macOS you can now use more than 8 cores on ARM chips.

A better solution is just to write a plain ass shell script that tests if various C snippets compile.

https://github.com/oilshell/oil/blob/master/configure

https://github.com/oilshell/oil/blob/master/build/detect-pwe...

Not an unholy mix of m4, shell, and C, all in the same file.

---

These are the same style as a the configure scripts that Fabrice Bellard wrote for tcc and QEMU.

They are plain ass shell scripts, because he actually understands the code he writes.

https://github.com/qemu/qemu/blob/master/configure

https://github.com/TinyCC/tinycc/blob/mob/configure

OCaml’s configure script is also “normal”.

You don’t have to copy and paste thousands of lines of GNU stuff that you don’t understand.

(copy of lobste.rs comment)

Related:

A fast Pascal (Delphi) WebAssembly interpreter:

https://github.com/marat1961/wasm

WASM-4:

https://github.com/aduros/wasm4

Curated list of awesome things regarding WebAssembly (wasm) ecosystem:

https://github.com/mbasso/awesome-wasm

Also, it would be nice if there was a WASM (soft) CPU for QEMU, which (if it existed!) would go here:

https://github.com/qemu/qemu/tree/master/target

> architectural registers are always updated

In tiny code, the guest registers (global TCG variables) are stored in the host's registers until you either call an helper which can access the CPU state or you return (`git grep la_global_sync`). This is the reason why QEMU is not so terribly slow.

But after a check, this also happens when you access the guest memory address space! https://github.com/qemu/qemu/blob/master/include/tcg/tcg-opc... (TCG_OPF_SIDE_EFFECTS is what matters)

But still, in the end, it's the same problem. What QEMU does, can be done in LLVM too. You could probably be more efficient in LLVM by using the exception handling mechanism (invoke and friends) to only serialize back to memory when there's an actual exception, at the cost of higher register pressure. More or less what we do here: https://rev.ng/downloads/bar-2019-paper.pdf