Blog
Build logs, project notes, and write-ups from the workshop.
- Welcome to the Garage Geek Guy blog A written companion to the YouTube channel — build logs, schematics, and project notes you can actually skim.
- How to Use the L298N Motor Driver with Arduino — Wiring + PWM Speed Control Everything you need to wire and code the L298N dual H-bridge motor driver with Arduino — IN1-4, ENA/ENB, common ground, PWM speed control, and the stall-current trick nobody documents.
- How to Measure Distance with an Arduino and HC-SR04 Ultrasonic Sensor The HC-SR04 is dollar-store radar for your Arduino — four pins, a library, and a few lines of code give you distance readings in centimeters. Here is how to wire it, code it, and deal with its quirks.
- How to Use a 1602 I2C Serial LCD Display with Arduino The parallel 1602 LCD needs 12 wires and a headache. The I2C version needs four. Here is how to wire it, install the library, and get text on screen in under ten minutes.
- How to Use a PIR Sensor to Detect Motion The HC-SR501 PIR sensor is one of the most practical components you can add to an Arduino project. Three wires, a handful of configuration options, and you have reliable motion detection for under $2.
- Adafruit GFX Library for Arduino — Draw Graphics on OLED + LCD Displays How the Adafruit GFX library works — coordinate system, screen buffer, and every drawing primitive from drawPixel to drawTriangle, demonstrated on a 128x64 SSD1306 OLED.
- Arduino OLED Display: Connect the 0.96" 128×64 SSD1306 The 0.96" OLED display gives you 128×64 pixels on an I²C bus for about $6. This post covers wiring, library installation, address scanning, and getting the Adafruit example running.
- How to Use RGB LEDs with Arduino RGB LEDs pack three LEDs into one package and unlock the full color spectrum with PWM. This post covers the hardware, wiring, and three progressively interesting sketches to get you mixing colors.
- Arduino: Play the Super Mario Bros Theme with tone() Arduino's built-in tone() function is all you need to play melodies — no libraries, no shield, just a speaker and a few lines of code. This post covers the basics and gets the Mario Bros theme running on your board.
- Arduino Potentiometer Tutorial — Build an LED Volume Bar with analogRead + map() Turn a potentiometer into a 19-LED volume bar indicator — a hands-on intro to analogRead, the map() function, and the for-loop pattern every analog Arduino project needs.
- How to Fix the Arduino Uno Serial Port Problem on Mac Arduino clone not showing a serial port in the IDE on macOS? The fix is a CH340 driver install plus one terminal command. Here is exactly what to do.
- TI-99/4A AV Cable DIY — Build a 5-Pin DIN to Composite Video Adapter Skip the RF modulator. A 5-pin DIN connector, a spare RCA cable, and an hour at the bench gives your TI-99/4A a clean composite video signal into any modern TV.
- How to Fix Nintendo Wii Disc Read Errors — Optical Drive Replacement Tutorial The dreaded "Unable to read disc" error on a Nintendo Wii is almost always the optical drive — and a $20 replacement from overseas plus one very specific screwdriver will fix it in about 35 minutes.
- How to Hack a TowerPro MG995 Servo for 360° Continuous Rotation Turn a sub-$10 metal-gear hobby servo into a high-torque gear motor that runs straight off an Arduino — no motor driver required. Full walkthrough of the physical mod, the resistor-divider trick, and the calibration step nobody warns you about.
- Program a TI Launchpad MSP430 Like an Arduino with Energia The TI MSP430 LaunchPad costs $4.30 and runs on the same code as an Arduino — thanks to Energia, a community-built IDE that ports the Arduino framework to TI microcontrollers.