Ken Shirriff's blog

The rise and fall of IBM's 4 Pi aerospace computers: an illustrated history

Instruction decoding in the Intel 8087 floating-point chip

Notes on the Intel 8086 processor's arithmetic-logic unit

Conditions in the Intel 8087 floating-point chip's microcode

The stack circuitry of the Intel 8087 floating point chip, reverse-engineered

Unusual circuits in the Intel 386's standard cell logic

Solving the NYTimes Pips puzzle with a constraint solver

A Navajo weaving of an integrated circuit: the 555 timer

Why do people keep writing about the imaginary compound Cr2Gr2Te6?

Here be dragons: Preventing static damage, latchup, and metastability in the 386

A CT scanner reveals surprises inside the 386 processor's ceramic package

How to reverse engineer an analog chip: the TDA7000 FM radio receiver

Reverse engineering the mysterious Up-Data Link Test Set from Apollo

Inside the Apollo "8-Ball" FDAI (Flight Director / Attitude Indicator)

Reverse engineering the 386 processor's prefetch queue circuitry

The absurdly complicated circuitry for the 386 processor's registers

A tricky Commodore PET repair: tracking down 6 1/2 bad chips

Notes on the Pentium's microcode circuitry

A USB interface to the "Mother of All Demos" keyset

The Pentium contains a complicated circuit to multiply by three

The origin and unexpected evolution of the word "mainframe"

Interesting BiCMOS circuits in the Pentium, reverse-engineered

Reverse-engineering a carry-lookahead adder in the Pentium

It's time to abandon the cargo cult metaphor

Pi in the Pentium: reverse-engineering the constants in its floating-point unit

Intel's $475 million error: the silicon behind the Pentium division bug

Antenna diodes in the Pentium processor

Wealth distribution in the United States

Reverse-engineering a three-axis attitude indicator from the F-4 fighter plane

Inside a ferroelectric RAM chip

The Pentium as a Navajo weaving

Inside the guidance system and computer of the Minuteman III nuclear missile