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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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An interactive Arduino Uno circuit simulation you can run free in your browser on Velxio, by zuleydithj20.
#include "Wire.h" // Librería nativa para comunicación I2C
#include "I2Cdev.h" // Librería auxiliar para control I2C del MPU6050
#include "MPU6050.h" // Librería específica para el MPU6050
#include "Adafruit_VL53L0X.h" // Librería oficial de Adafruit para el sensor láser VL53L0X
MPU6050 mpu; // Instancia del objeto MPU6050
Adafruit_VL53L0X lox = Adafruit_VL53L0X(); // Instancia del objeto VL53L0X
// Variables para el acelerómetro (MPU6050)
int ax, ay, az; // Variables para almacenar los valores en crudo
int ax_o, ay_o, az_o; // Variables para los offsets de calibración
void setup() {
Serial.begin(115200); // Iniciamos el puerto serial a alta velocidad
Wire.begin(); // Iniciamos el bus I2C del microcontrolador
pinMode(12, OUTPUT);
digitalWrite(12, LOW);
mpu.initialize(); // Inicializamos el acelerómetro/giroscopio
if (mpu.testConnection()) {
Serial.println("MPU6050 conectado correctamente.");
} else {
Serial.println("Error al conectar el MPU6050. Revisa las conexiones I2C.");
}
// Offsets actuales grabados en el sensor
ax_o = mpu.getXAccelOffset();
ay_o = mpu.getYAccelOffset();
az_o = mpu.getZAccelOffset();
// Verificamos si el sensor láser responde en su dirección I2C por defecto (0x29)
if (!lox.begin()) {
Serial.println("Error al iniciar el VL53L0X. Revisa la alimentacion y pines SDA/SCL.");
while (1); // Si falla, detenemos el programa
} else {
Serial.println("VL53L0X (Sensor laser de distancia) iniciado correctamente.");
}
}
void loop() {
// Leemos los valores de aceleración en crudo (RAW) de los 3 ejes
mpu.getAcceleration(&ax, &ay, &az);
// Calculamos los ángulos de inclinación en grados usando trigonometría (arcotangente)
float accel_ang_x = atan(ax / sqrt(pow(ay, 2) + pow(az, 2))) * (180.0 / 3.14159265);
float accel_ang_y = atan(ay / sqrt(pow(ax, 2) + pow(az, 2))) * (180.0 / 3.14159265);
// Calcular distancia con el VL53L0X
VL53L0X_RangingMeasurementData_t measure; // Estructura de datos nativa
lox.rangingTest(&measure, false); // Realizamos la medición de distancia láser
int distancia_mm = 0;
// Verificamos si la lectura del sensor láser es válida (estado 4 = rango válido)
if (measure.RangeStatus != 4) {
distancia_mm = measure.RangeMilliMeter; // Obtenemos la distancia en milímetros
} else {
distancia_mm = 2000; // Fuera de rango (>2 metros)
}
// Condición de alerta: Si un objeto está a 1.5 metros (1500 mm) o menos, activamos el zumbador
if (distancia_mm <= 1500) {
digitalWrite(12,HIGH);
} else {
digitalWrite(12, LOW);
}
// Imprimir resultados en el Monitor Serial
Serial.print("Inclinacion X: "); Serial.print(accel_ang_x); Serial.print(" deg \t");
Serial.print("Inclinacion Y: "); Serial.print(accel_ang_y); Serial.print(" deg \t");
Serial.print("Distancia Laser: "); Serial.print(distancia_mm); Serial.println(" mm");
delay(10