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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.

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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 Xiao Esp32C6 circuit simulation you can run free in your browser on Velxio, by itsmebenn.
// Grove - AHT20 on XIAO ESP32-C6 (adapted from the Seeed wiki, MIT)
// SDA -> D4 (GPIO22), SCL -> D5 (GPIO23). I2C address 0x38.
// #include <Wire.h>
// const uint8_t ADDR = 0x38;
// void setup() {
// Serial.begin(115200);
// Wire.begin(22, 23);
// delay(100);
// }
// void loop() {
// Wire.beginTransmission(ADDR);
// Wire.write(0xAC); Wire.write(0x33); Wire.write(0x00); // trigger
// Wire.endTransmission();
// delay(80);
// Wire.requestFrom(ADDR, (uint8_t)7);
// if (Wire.available() == 7) {
// uint8_t b[7];
// for (int i = 0; i < 7; i++) b[i] = Wire.read();
// uint32_t rawH = ((uint32_t)b[1] << 12) | ((uint32_t)b[2] << 4) | (b[3] >> 4);
// uint32_t rawT = ((uint32_t)(b[3] & 0x0F) << 16) | ((uint32_t)b[4] << 8) | b[5];
// Serial.print("T = ");
// Serial.print(rawT * 200.0f / 1048576.0f - 50.0f, 2);
// Serial.print(" C RH = ");
// Serial.print(rawH * 100.0f / 1048576.0f, 1);
// Serial.println(" %");
// }
// delay(1000);
// }
#include <Wire.h>
#include <Adafruit_AHTX0.h>
// KONFIGURASI I2C PIN (Untuk ESP32-S3 Anda)
#define I2C_SDA_PIN 22
#define I2C_SCL_PIN 23
// Buat objek sensor
Adafruit_AHTX0 aht;
void setup() {
Serial.begin(115200);
// Memulai I2C secara spesifik di pin 8 dan 9
Wire.begin(I2C_SDA_PIN, I2C_SCL_PIN);
Serial.println("Mencari sensor AHT20...");
// Inisialisasi sensor menggunakan library
if (!aht.begin()) {
Serial.println("Gagal menemukan AHT20! Periksa kembali kabel SDA dan SCL.");
while (1) delay(10); // Hentikan program jika sensor tidak terdeteksi
}
Serial.println("Sensor AHT20 berhasil dihubungkan!\n");
}
void loop() {
// Siapkan "wadah" untuk menyimpan data suhu dan kelembaban
sensors_event_t humidity, temp;
// Perintahkan library untuk membaca data ke dalam wadah tersebut
aht.getEvent(&humidity, &temp);
// Tampilkan hasilnya ke Serial Monitor (dengan format desimal)
Serial.print("T = ");
Serial.print(temp.temperature, 2);
Serial.print(" C RH = ");
Serial.print(humidity.relative_humidity, 1);
Serial.println(" %");
// Beri jeda 1 detik (karena ini hanya tes tunggal, pakai delay biasa tidak masalah)
delay(1000);
}