Board

Arduino Uno simulator, wired to a real breadboard

Mokxi models an Arduino Uno R3 down to the ATmega328P. Three timers in every waveform mode, USART0, the ADC, external and pin-change interrupts, sleep, EEPROM and the self-programming instruction. It runs at 16 MHz and at real time, next to a breadboard that behaves like one.

Start building free

6peripheral areas modeled
581projects ready to run
Real timeon your own machine

Arduino Uno R3: blinklive0.000 s 0.00x

Click to open it in the editor

The board is running real firmware right now. Click it to open the circuit in the editor.

The model

What is modeled

Taken from the board's own contract document and put in plain words, with what is missing beside it.

Modeled

Core: Every ATmega328P mnemonic with datasheet cycle counts
Timers: Three, in every waveform mode, including hardware PWM
USART0: Wired to the serial monitor, paced at the baud rate you set
ADC: On the analog pins, with the reference options
Interrupts: External and pin-change, with the real vector table
Sleep and EEPROM: Both, so an idle sketch costs almost nothing to simulate

Not modeled

Shields, as physical parts. Wire the same circuit on the breadboard instead.
The Arduino IDE library ecosystem. The runtime here is ours and Arduino-shaped, not the Arduino core.

Start here

Open one and press Run

Each of these opens in the editor exactly as it is drawn here.

Projects

Every built-in project on the Arduino Uno

Each has its own page with the circuit running, the code and a parts list.

Parts

Parts wired to the Arduino Uno, step by step

Each page has the wiring with the Arduino Uno’s own pin names, the code, the common mistakes and the circuit running.

Libraries

Arduino libraries that compile as they are

Paste a tutorial that includes one of these and it builds. For any other library, the build names the Mokxi header that does the same job.

Servo.h

attach, write, writeMicroseconds, read, detach, on any pin

Wire.h

I2C as a master; Wire.begin() puts it on A4 (SDA) and A5 (SCL)

SPI.h

transfer and transactions, on the board’s usual SPI pins

EEPROM.h

read, write, update, get, put and EEPROM[i], kept in the chip’s own 1 KB EEPROM

LiquidCrystal_I2C.h

the 16x2 LCD behind its I2C backpack

Adafruit_GFX.h and Adafruit_SSD1306.h

the 128x64 I2C OLED: text, pixels, lines, rectangles, circles, triangles and bitmaps

Adafruit_NeoPixel.h

WS2812 strips and panels

DHT.h

the DHT11 and DHT22: temperature, humidity and the heat index, as floats you can print

And 15 more, 23 in all: OneWire.h and DallasTemperature.h; Adafruit_BME280.h, Adafruit_BMP280.h and SparkFunBME280.h; RTClib.h; Adafruit_SHT31.h; Adafruit_PCF8591.h; Adafruit_ADXL345_U.h; LedControl.h; Adafruit_LEDBackpack.h; Adafruit_TCS34725.h; Adafruit_SGP30.h; Adafruit_INA219.h; Adafruit_ADS1X15.h; Adafruit_MCP23X17.h; Bounce2.h; HX711.h.