Arduino has become a household name in the makers and hardware industry mostly thanks to it’s low-cost, easy to use the platform and the amazing community it has created over the years. Nevertheless, not everyone can always get access to an Arduino or a sensor, shield, or something to test run an idea, giving rise to the possibility of using simulators.
Arduino simulators haven’t necessarily been a household name, mostly becomes it is super easy to get an Arduino, one is probably lying next to you, and most simulators don’t work as expected as you wish. In the last 10 years, I think I have roughly tried 2 0r 3 simulators in the past: Proteus VSM and Autodesk TinkerCad. One thing familiar with most of those simulator platforms is that they are closed projects, and you are the mercy of the creators, which is something AVR8js is attempting to solve.
AVR8js is an AVR simulator that allows you to compile and run Arduino code directly in your browser!. AVR8js is open source in nature, and you clone the project and make modifications as you wish. Currently, there are examples of simulating multiple LEDs and even serial output.