A drop-in ROM replacement for vintage 8-bit computers that solves the fundamental limitations of existing solutions. Built around an STM32F4 microcontroller, SDRR delivers true flexibility, replacing 2364, 2332 and 2316 ROMS, through software configuration while fitting in the exact footprint of the ROM socket.

This video introduces the project and demonstrates why existing ROM replacements fall short - from inflexible hardware configurations requiring physical modifications, to tedious programming workflows that interrupt development, to bulky adapters that may not fit properly in existing systems.

SDRR addresses these problems with a software-defined approach: configure ROM types and chip select behavior through makefile configuration, reprogram in-system via 3-wire SWD without removing the chip, and achieve all this in a compact design that fits the original 2364/2332/2316 ROM footprint.

Live demonstrations show SDRR working in C64 and VIC-20 systems, including real-time reprogramming and configuration changes. The complete solution costs under $5 per board in low volumes (much cheaper in high volumes) and is fully open source.

Perfect for diagnostics, development, system restoration, and anyone working with PET, C64, VIC-20, IEC and IEE disk drives, and other 8-bit systems requiring 2364, 2332, or 2316 ROM replacements.

Github Repo: https://piers.rocks/u/sdrr

⏰ Timestamps
00:00 🚀 Introduction
00:12 📋 Background
01:33 🔒 Today’s ROMs - inflexible
02:46 ⏳ Today’s ROMs - tedious programming
04:26 📦 Today’s ROMs - bulky replacements
05:15 🎯 Solution - flexibility
05:47 ⚡ Solution - easy programming
06:16 📏 Solution - compact
06:26 💰 Solution - low cost
06:48 🔓 Solution - fully open source
07:00 🖥️ Demo - C64 kernal
07:50 🔧 Demo - C64 dead test ROM
08:26 🎨 Demo - C64 character ROM
09:34 🔄 Demo - reprogramming in-situ
12:09 ⚙️ Demo - ROM config
13:46 🛠️ Demo - building and flashing
14:55 🎮 Demo - Vic-20 dead test ROM
15:34 📂 Open source
15:47 💸 Build cost
16:28 🎬 Wrap up

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