How it's done - Software Defined ROMs

The engineering deep-dive behind Software Defined Retro ROM: real-world MCU selection criteria, schematic design failures, PCB layout decisions, and embedded implementation choices that made nanosecond ROM emulation possible.

This video breaks down the technical decisions behind SDRR - from why I didn’t choose the Pico, ATMEGA or STM32F103, to PCB layout and routing in a two layer compact form factor, finishing off with scoping the working solution.

Previous video (introduction): https://youtu.be/Jhe4LF5LrZ8
Github repo: https://piers.rocks/u/sdrr

⏰ Timstamps
00:00 🚀 Introduction
00:44 📄 Original ROM datasheet
05:13 📝 Requirements
06:55 ⚠️ Constraints
08:49 🎯 MCU Family Selection
13:19 ❌ STM32F1 (Failed) Schematic
17:40 ✅ STM32F4 Schematic
22:16 🔌 PCB Layout
25:00 💾 ROM Code
29:33 🔬 Scoping the Software ROM
31:15 🎬 Wrap up