Debugging an Arduino Sketch Running on an Uno

How to build a hardware debugger that allows you to debug Arduino programs running on an Arduino Uno or ATtiny in 4 easy steps.
Background article: https://www.codeproject.com/Articles/5321801/Debugging-an-Arduino-project-with-GDB-on-Classic-A
Code repository: https://github.com/felias-fogg/dw-link

If you want to build a hardware debugger that is a little bit more durable, then visit: https://hinterm-ziel.de/index.php/2022/01/13/a-debugwire-hardware-debugger-for-less-than-10-e
There is also the luxury version (which requires SMD soldering): https://hinterm-ziel.de/index.php/2022/01/04/dw-probe-the-hardware-for-the-hardware-debugger/

Table of Contents:
00:26 - Motivation
01:32 - GDB: The GNU Project Debugger
01:44 - Embedded Debugging
05:04 - Step 1: Install PlatformIO
08:31 - Step 2: Install firmware for HW debugger
11:08 - Step 3: Connect debuggger to target
16:42 - Step 4: Start debugging