Interactive 8086 Microcode Browser: Exploring the Original Intel Processor's Internal Architecture
By
zdw
Lightly toasted, lightly seasoned, mostly correct.
Summary
A developer has created an interactive online browser for the 8086 microprocessor's microcode ROM, based on extensive research and notes taken while studying the original 8086 chip. The project emerged from work on recreating the 8086 with a design faithful to the original, which led to deep exploration of the microcode extracted and disassembled by Andrew Jenner in 2020. The browser provides interactive access to the entire 8086 microcode, revealing the subtle behavior hidden below the assembly layer in microcoded CPUs.
Key quotes
· 5 pulledSince releasing 486Tang, I've been working on recreating the 8086 with a design that stays as faithful as possible to the original chip.
That exploration naturally led me deep into the original 8086 microcode — extracted and disassembled by Andrew Jenner in 2020.
Like all microcoded CPUs, the 8086 hides a lot of subtle behavior below the assembly layer.
While studying it I kept extensive notes, and those eventually evolved into something more useful: an interactive browser for the entire 8086 microcode ROM.
So here it is: the online 8086 microcode browser.
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