void setup() { pinMode(13, OUTPUT); Serial.begin(9600); }
void loop() { digitalWrite(13, HIGH); Serial.println("LED ON"); delay(500);
digitalWrite(13, LOW);
Serial.println("LED OFF");
delay(500);In Velxio you can connect an LED to pin 13 and watch it blink, while the Serial Monitor prints the messages in the terminal.
A fully local, open-source Arduino emulator. Write Arduino code, compile it, and simulate it with real AVR8 CPU emulation and 48+ interactive electronic components,All running in your browser. GitHub: https://github.com/davidmonterocrespo24/velxio
The goal of this project was to learn more about how emulators work internally: CPU instructions, memory management, and low-level architecture.
It's still experimental, but it already runs basic instructions and I'm continuing to improve it.
All I see are dependencies that are glued together with claude.
Can you clearify exactly what you have developed?
The browser-based IDE (editor, project handling, UI)
The circuit simulation layer that connects components to the emulator
The glue between the AVR8 emulator and the virtual peripherals (GPIO, UART, SPI, etc.)
The component interaction system (buttons, LEDs, displays, etc.)
The architecture that lets compiled Arduino sketches run and interact with the simulated hardware
Some parts like the AVR CPU emulation and the compiler toolchain obviously come from existing projects, but the goal of Velxio wasn't to re-implement an AVR core from scratch. It was to build a usable environment where all of these pieces work together in the browser.
I'm still having trouble connecting the cables and components properly. I'm looking for a better algorithm. I'm also trying to create a real-world electronics simulator in JavaScript using an engine like CircuitJS1.
I built Velxio to explore how microcontroller emulators work internally.
It's an Arduino environment that runs entirely in the browser. You can write sketches, compile them with arduino-cli, and simulate circuits using a real AVR8 CPU emulator.
Features: - Arduino Uno / Nano support - Raspberry Pi Pico (RP2040) - GPIO, SPI, I2C, UART, ADC peripherals - interactive electronic components
The goal is to create an open-source environment for experimenting with embedded systems without installing anything.
I'd love feedback from embedded developers!
In the future I'd like to support more low-level experimentation though (bare-metal programs, custom runtimes, etc.).
Thanks for checking it out!
[Edit] Which also does Arduino.