How I built a ZX Spectrum emulator from scratch using C# and Blazor

on YouTube ↗50m

" summary

A ZX Spectrum emulator written in C# and Blazor WebAssembly that runs at 3.5 MHz and 50 FPS, implements ~1,000 prefixed instructions on top of 256 base opcodes and executes roughly 10,000 instructions per 20 ms. Memory, ZX screen layout and 8×8 attribute color clashes are faithfully reproduced, audio uses 20 ms buffering to JavaScript audio context, gamepad and keyboard map to Kempston, heavy unit tests cover every CPU operation, and Skia compiled to WebAssembly yields near‑native rendering performance.

AI-written summary · about

" chapters (16)

1. 0:00Introduction
2. 7:24From emulation to web
3. 10:43Z80 assembly basics
4. 18:12Z80 instructions & registers
5. 21:06Memory & screen rendering
6. 26:57Input, keyboard & sound
7. 29:05Hardware to software
8. 30:30Early emulator versions
9. 33:46MVP journey
10. 37:29Podcasts, Twitch and YouTube expansion
11. 39:13MVP & Unity emulator
12. 40:14Blazor web emulator
13. 41:18Audio & gamepad
14. 43:05Screen rendering with Skia
15. 46:38Live demo
16. 48:36Future plans

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