Source: https://mokxi.com/learn/path/interactive-devices Updated: 2026-11-11 All paths # Interactive devices on the Uno Read people and sensors without blocking, control an output, then finish with two playable builds. Arduino Uno R3 Free 9 lessons 8 h 4 chapters 2,080 XP Embedded engineering ยท Beginner +100 XP 0 of 9 done Start the course free Reading a pin, and the pull-up Lesson plan for teachers What you will build ## 4 projects, built step by step 9 lessons in 4 chapters, about 8 hours on a simulated Arduino Uno R3. Free, in your browser, every step checked by the simulator. Chapter 1 project ### Press once for on, once for off The difference between a level and an edge, a variable that remembers, and the debounce window that makes a mechanical switch usable. Open it in the simulator Chapter 2 project ### Blinking and listening at the same time The payoff for non-blocking code: a board that keeps a rhythm and still answers a button in microseconds. Feel the difference by breaking it. Open it in the simulator Chapter 3 project ### Brightness from a digital pin Eight duty cycles on pin 9 next to a pin that can only be on or off. What PWM is, which pins have it, and what it is not good for. Open it in the simulator Chapter 4 project ### Project: a metronome A click on a piezo, a lamp on the beat, and two buttons that change the tempo without missing one. Making a note out of a pin. Open it in the simulator The map ## Chapter by chapter Each lesson opens when the one before it is done, and each chapter ends in a project. Chapter 1 ## Read intent Wire a button correctly and turn a changing level into one deliberate action. Open 160 XP ### Reading a pin, and the pull-up A button with no resistor of its own, an input that must never float, and why pressed reads low. The single most common wiring in embedded work. 0 of 6 steps Start What is in it Project Locked 320 XP ### Press once for on, once for off The difference between a level and an edge, a variable that remembers, and the debounce window that makes a mechanical switch usable. 0 of 6 steps Chapter 2 ## Stay responsive Measure elapsed time so one job never makes the board deaf to another. Locked 160 XP ### Two rates at once, without delay The pattern that unlocks everything else: keep when each thing last happened, and ask the time instead of waiting for it. 0 of 6 steps Project Locked 320 XP ### Blinking and listening at the same time The payoff for non-blocking code: a board that keeps a rhythm and still answers a button in microseconds. Feel the difference by breaking it. 0 of 6 steps Chapter 3 ## Sense and act Turn a changing voltage into a stable decision and a proportional output. Locked 160 XP ### Reading a voltage The ADC turns a voltage into a number from 0 to 1023. Build a divider, read two taps of it, and work out what a count is worth. 0 of 6 steps Locked 160 XP ### Deciding from a reading A lamp that fades up when the sensor says dark, and an indicator that does not. What a threshold is, why a ramp looks better than a jump, and where hysteresis comes in. 0 of 6 steps Project Locked 320 XP ### Brightness from a digital pin Eight duty cycles on pin 9 next to a pin that can only be on or off. What PWM is, which pins have it, and what it is not good for. 0 of 6 steps Chapter 4 ## Finished builds Use inputs, timing and feedback together in two projects you can play. Locked 160 XP ### Project: a reaction timer A lamp at a random moment, a button, and the milliseconds in between. Randomness, measuring time, and catching a cheat. 0 of 6 steps Project Locked 320 XP ### Project: a metronome A click on a piezo, a lamp on the beat, and two buttons that change the tempo without missing one. Making a note out of a pin. 0 of 6 steps Syllabus ## Every lesson in the course All 9 lessons, in order, each with what it covers. Any of them opens in the editor right away. Chapter 1 ### Read intent - Reading a pin, and the pull-up A button with no resistor of its own, an input that must never float, and why pressed reads low. The single most common wiring in embedded work. - Press once for on, once for off The difference between a level and an edge, a variable that remembers, and the debounce window that makes a mechanical switch usable. Chapter 2 ### Stay responsive - Two rates at once, without delay The pattern that unlocks everything else: keep when each thing last happened, and ask the time instead of waiting for it. - Blinking and listening at the same time The payoff for non-blocking code: a board that keeps a rhythm and still answers a button in microseconds. Feel the difference by breaking it. Chapter 3 ### Sense and act - Reading a voltage The ADC turns a voltage into a number from 0 to 1023. Build a divider, read two taps of it, and work out what a count is worth. - Deciding from a reading A lamp that fades up when the sensor says dark, and an indicator that does not. What a threshold is, why a ramp looks better than a jump, and where hysteresis comes in. - Brightness from a digital pin Eight duty cycles on pin 9 next to a pin that can only be on or off. What PWM is, which pins have it, and what it is not good for. Chapter 4 ### Finished builds - Project: a reaction timer A lamp at a random moment, a button, and the milliseconds in between. Randomness, measuring time, and catching a cheat. - Project: a metronome A click on a piezo, a lamp on the beat, and two buttons that change the tempo without missing one. Making a note out of a pin. Keep going ## The next course on your track Interactive devices on the Uno is part of the embedded track, a ladder of courses from zero to expert. Next course ### Talk to chips: I2C, SPI and UART The three buses every sensor, screen and radio speaks, on the Uno: serial between two boards, I2C scans and shared buses, SPI screens and an SD card, the logic analyzer, and a weather station that uses them all. Open the next course Track ### Embedded track Arduino, ESP32, Raspberry Pi Pico and STM32: pins, timing, buses, motors, WiFi, registers and debugging, every lesson checked on a simulated board. See every course on the track Kits ## Build it on your bench too Every lesson runs in the simulator with nothing to buy. When you want the real thing, these kits have the parts. Have a kit already? ### Find your kit Pick the starter kit you own and run every lesson in its manual with the same parts on the same pins. See every kit Questions ## About Interactive devices on the Uno Is Interactive devices on the Uno free? Yes. All 9 lessons of Interactive devices on the Uno are free and run in your browser, with nothing to install and no parts to buy before you start. Do I need a real Arduino Uno R3? No. Every lesson runs on a simulated Arduino Uno R3 with its parts on the canvas, and the simulator checks each step as you go. When you want to build it for real, the same wiring and code work on a real board. How long does Interactive devices on the Uno take? About 8 hours: 9 lessons in 4 chapters, each one a few short steps. Your progress is kept, so you can stop after any lesson and pick up where you left off. What will I build? Each chapter ends in a project that puts it together: Press once for on, once for off, Blinking and listening at the same time, Brightness from a digital pin and Project: a metronome. Where do I start? With "Reading a pin, and the pull-up", and each lesson builds on the one before it. New to circuits? Electronics basics is the course that starts from zero.