Address & Data Decoder for my 8-bit Computer Project

What happens when you build a debugger for your homebrew 8-bit computer... and accidentally violate the datasheet? In this episode, I’m showing off my first fully working peripheral for the SEBA-1 bus: a real-time address & data debugger built entirely from TTL chips - no microcontrollers involved. It reads 24-bit addresses and 8-bit data from the bus and displays them using 7-segment LED displays. It’s overengineered. Slightly. And yes - I’ll also show you what I did wrong and what I learned along the way. 📄 Want to take a closer look? You can download the full schematic here: 👉 https://github.com/kaligari/seba-1/tree/main/docs/bus-debugger 🎯 What’s inside: ▶ How the debugger reads the bus using only logic chips ▶ Using EEPROM as a segment lookup table ▶ Address decoding, write detection, and RESET hacks ▶ Design flaws, hot 245s, and why it somehow still works ▶ A preview of what’s coming next: CPU, LCD & keyboard input 🧰 Tech featured in this episode: • SEBA-1 custom ribbon bus (IDC40) • 74LS151, 74LS137, 74LS245 • AT28C16 EEPROM • Common-cathode 7-segment displays • A lot of bodges and TTL soul 💬 Got questions? Ideas? Drop a comment — I read all of them 📡 Subscribe for more TTL madness, retro computing, and too many wires. 🎙️ Voice generated with the help of AI — because soldering and narrating at the same time is tricky ;) #retrocomputing #6502 #diyelectronics #seba1 #ttl