qucs_s VS avr8js

When talking about open source tools, here are some:

KiCad may be used as a schematic entry tool for ngspice, especially for discrete or PCB-based electronics. You may watch several simulation examples (including oscillators) here: https://forum.kicad.info/t/simulation-examples-for-kicad-ees.... KiCad integrates ngspice internally, but may also provide external ngspice with netlists for simulation.

Another GUI to ngspice is XSCHEM, especially useful for IC design work (see https://xschem.sourceforge.io/stefan/index.html). Device models are available by the Open Source PDKs from Google/Skywater, Google/GF, or IHP. A growing community is supporting digital, analog or mixed-signal design flows.

QUCS-S (https://ra3xdh.github.io/) is a GUI for ngspice or XyCE.

Indeed device models have to be added manually to the devices in the circuit schematic, when invoking ngspice via KiCad or QUCS-S, except for some basic devices with integrated models. Models are provided by device makers, distributors or web sites like this one: https://ngspice.sourceforge.io/modelparams.html .

https://ra3xdh.github.io/ (QUCS-S - seems to be active)

​https://ra3xdh.github.io/

https://ra3xdh.github.io

It's still missing a comprehensive component library like LTspice does, though.

KiCad can also simulate circuits through NGSpice, but it's missing a library and suffers from a lot of quirks.

Also see Qucs-S, which is a GUI for ngspice and a few other engines.

https://ra3xdh.github.io/

Try https://github.com/ra3xdh/qucs\s)

Wokwi is free open source and neat with an MIT license https://github.com/wokwi/avr8js https://wokwi.com

What I really want is a modern microcontroller emulator. avr8js is really spectacular. Execute Code provides a great way to run C, C++, and Rust snippets, but running a program on an OS versus on an MCU is very different and code is generally not very portable between them.

We simulate the actual Arduino hardware (based on this avr8js repo) which runs the compiled Arduino code. To compile the code itself, we use Arduino CLI.

Check out something like https://github.com/wokwi/avr8js

Here Uri is tackling a subtle but impactful bug in the AVR simulator. He starts by analyzing a tiny Arduino program that shows the problem: an LED turns off when it shouldn't. Then we dive into the assembly code, and take a look at the implementation of the offending instructions in the simulator's source code. Once we pinned down the bug (pun intended), we create a regression test case and change the simulator's code until the tests are all green again. Enjoy the ride! ▸ GitHub issue with the all details: https://github.com/wokwi/avr8js/issue... ▸ Wokwi online Arduino simulator: https://wokwi.com

I hope you have heard about the Wokwi Arduino Simulator. There is an engine thatthat is open source. You can hop on the discord channel and get more help/support from the community over there. there are a lot of welcoming active people helping out each other.

This is a completely free Arduino simulator based on the AVR8js engine (open-source on GitHub)/

I don't know whether you saw it, but /u/wokwi has actually done a similar thing with https://github.com/wokwi/avr8js in a totally different way - no WASM, an AVR implementation in JavaScript. Total madness but it works!