For years, it's generally accepted that 8 bit microcomputer CPUs does not have hardware support for protected mode. However, my recent discovery shows otherwise. In this video, I will show you how to implement memory and I/O protection on a z80 with minimal external circuit. Links: General Introduction to the Z80: https://www.youtube.com/watch?v=P9mIXXlxceM The history of Zilog and Z80: https://www.youtube.com/watch?v=P1aqtfXUCEk Z80 assemnly tutorial: https://www.youtube.com/watch?v=_J4ahkWtNYw&list=PLPSrOWYluVLJyKIIDxlBtwkFC5lCE3xnY Edit: this video is the third release! I managed to iron out all problems in the second one, which includes: 1, CRT noise everywhere 2, intro video footages are not muted (you can hear computer noise over the music) 3, 0:55 the (absolutely terrible) B-roll is not muted (You can hear me watching a video about the Mindset computer in the background... I thought it was fine since I could just mute that, obviously I did not...) 4, 1:56 my voice is strangely 'doubled' making me sound like the Borg Queen (this does not happen at all when I'm editing the video! In my editing software the two vioces just overlap entirely and become louder) 5, 2:13 that B-roll (and the horrible CRT noise) is not muted 6, 2:45 a weird 'ding' caused by speeding up the video to hide a long blank 7, music is still too loud, but my editing machine probably have a voice enhance feature enabled somewhere too. This problem is much less pronounced on it (and maybe some other computers but probably not all). Chapters: 0:00 The Z80 has a protected mode 0:32 Literally the worst intro video ever 0:52 What is Z80 1:52 Why is protected mode important? 3:10 Undocumented? Really? 4:10 How to implement protected mode 10:34 Final Conclusion 12:10 Clickbait? 12:54 Applications of the protected mode 14:27 An interesting story