Arduino, running the sketch you wrote
arduino-cli compiles it, an AVR8 core executes it instruction by instruction, and the LCD shows what the ATmega328P actually put on the bus. Uno, Nano, Mega and ATtiny85, no board on your desk.

Hardware is all about iteration. Velxio lets you wire a circuit, program the board and run it in seconds, real firmware on a real solver, right in the browser.
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Nothing on this page is a scripted animation: the firmware is compiled and executed, and the circuit around it is solved.
arduino-cli compiles it, an AVR8 core executes it instruction by instruction, and the LCD shows what the ATmega328P actually put on the bus. Uno, Nano, Mega and ATtiny85, no board on your desk.

arduino-cli or ESP-IDF compiles the sketch, then AVR8, RP2040, RISC-V, Xtensa or ARM executes it instruction by instruction. What the OLED draws and what the serial monitor prints is what the chip actually did.

ngspice compiled to WebAssembly runs a full nodal analysis about 60 times a second. GPIO pins drive real nets, ADC inputs read solved node voltages, and probes report RMS, DC and current wherever you drop them.

Adders, comparators, decoders, flip-flops and a 1-bit ALU slice: no microcontroller anywhere, just gates, switches and LEDs solved as a real net. The classroom half of electronics, without the breadboard.

The M5Stack Cardputer with its keyboard, Seeed's round display keeping time, Pimoroni's Badger 2350 driving e-paper, and DFRobot's UNIHIKER M10 in the catalogue alongside them. Their makers sent the hardware so the emulation could be checked against the real thing.




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Arduino, ESP32, RP2040, STM32, ATtiny and Raspberry Pi, with SPICE analog solved alongside the firmware. Not a sandboxed mock.
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Проверка шаго шкалы
An interactive ESP32-S3 circuit simulation you can run free in your browser on Velxio, by zdelnik84.
#include <Arduino.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
// =====================================================
// ESP32-S3 + NEMA17 + A4988 + OLED + ENCODER + LIMIT
// WOKWI VERSION
// =====================================================
// ---------------- OLED ----------------
#define OLED_SDA 17
#define OLED_SCL 18
#define OLED_ADDR 0x3C
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(
SCREEN_WIDTH,
SCREEN_HEIGHT,
&Wire,
-1
);
// ---------------- A4988 ----------------
#define STEP_PIN 4
#define DIR_PIN 5
#define EN_PIN 6
// ---------------- ENCODER ----------------
#define ENC_CLK 8
#define ENC_DT 9
#define ENC_SW 10
// ---------------- LIMIT SWITCH ----------------
#define LIMIT_PIN 11
// =====================================================
// НАСТРОЙКИ
// =====================================================
// Шагов на один щелчок энкодера
#define STEPS_PER_CLICK 10
// Задержка между шагами
#define MOVE_DELAY 800
// Скорость поиска концевика
#define HOME_DELAY 1200
// Направление поиска нуля
#define HOME_DIRECTION LOW
// Направление движения вперед
#define FORWARD_DIRECTION HIGH
// =====================================================
// ПЕРЕМЕННЫЕ
// =====================================================
long currentPosition = 0;
bool homed = false;
int lastEncoderState;
bool lastButtonState = HIGH;
unsigned long lastButtonTime = 0;
// =====================================================
// ОДИН ШАГ
// =====================================================
void makeStep(bool direction, int stepDelay)
{
digitalWrite(DIR_PIN, direction);
digitalWrite(STEP_PIN, HIGH);
delayMicroseconds(3);
digitalWrite(STEP_PIN, LOW);
delayMicroseconds(stepDelay);
}
// =====================================================
// КОНЦЕВИК
// =====================================================
bool limitPressed()
{
return digitalRead(LIMIT_PIN) == LOW;
}
// =====================================================
// OLED
// =====================================================
void updateDisplay()
{
display.clearDisplay();
display.setTextColor(SSD1306_WHITE);
display.setTextSize(1);
display.setCursor(0, 0);
display.println("NEMA17 CONTROLLER");
display.drawLine(0, 12, 127, 12, SSD1306_WHITE);
display.setCursor(0, 18);
if (!homed)
{
display.println("SEARCH HOME...");
}
else
{
display.println("READY");
}
display.setTextSize(2);
display.setCursor(0, 36);
display.print("STEP:");
display.setCursor(65, 36);
display.print(currentPosition);
display.display();
}
// =====================================================
// ПОИСК НУЛЯ
// =====================================================
void findHome()
{
homed = false;
currentPosition = 0;
updateDisplay();
digitalWrite(EN_PIN, LOW);
Serial.println("Searching HOME...");
while (!limitPressed())
{
makeStep(HOME_DIRECTION, HOME_DE