A side-by-side comparison of the three serial buses every microcontroller project runs into — I2C, SPI and UART — across four axes: number of signal lines, speed, how many devices you can hang off them, and wiring distance. Includes a decision flow and what to look for on a scope.
A thorough guide to using the 74HC595 with Arduino. Expand your GPIO without limit using just three signal lines — from shiftOut() to hardware SPI, with schematics, KiCad design files, and sample code. Fully compatible with the Arduino UNO R4.
Digital pins can normally only output HIGH or LOW. Using the Arduino UNO R4’s fast clock, we drive all 20 pins with Software PWM to render three different waves of light — complete with gamma correction and full source code.
Receive and decode IR remote control signals with Arduino, then use them to control 6 LEDs. Complete guide covering IR communication principles, hex signal decoding with IRremote, and step-by-step dimmer implementation — with circuit diagrams and full sample code.
A complete guide to controlling full-color RGB LEDs with Arduino PWM. From basic 8-color digital output to smooth 16.7 million color gradients using three-phase sine waves — with circuit diagrams and ready-to-use sample code.
Read sensor voltages with the Arduino ADC and stream them to the serial monitor in real time. Covers 10-bit vs. 14-bit resolution, the voltage conversion formula, and PWM output — with code that runs on both R3 and R4.
Build a playable electronic piano with an Arduino UNO R4 and a passive piezo buzzer. Complete with a note-to-frequency table, circuit diagram, annotated code, demo videos, and an FAQ covering the usual pitfalls — finished in about an hour.
Learn how to safely light up an LED using Ohm’s Law. Calculate the correct resistor value, wire a breadboard circuit, and avoid common mistakes — a complete beginner’s guide.