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Ken Shirriff
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I took die photos of Intel's first chip and reverse-engineer how this memory chip worked.

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I try Bitcoin mining on the 1973 Xerox Alto. So slow it would take thousands of times the age of the Universe to successfully mine bitcoins.

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I used the suggestions from some readers and optimized my Mandelbrot set on the vintage Xerox Alto to run in 9 minutes instead of an hour.

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I use the 1970s Xerox Alto to generate a Mandelbrot set. Very slow but demonstrates the high-res graphics. I wrote the program in BCPL, the typeless precursor to C.

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I reverse engineer the sound chip used in Space Invaders and explain in detail the analog circuits that generated a variety of sound effects.

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Here's how taxes were done in the 1950s - the wiring panel that controlled a one-ton electromechanical IBM accounting machine.

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The 74181 ALU chip powered many minicomputers of the 1970, but provides some bizarre functions. I reverse-engineer the chip and explain the logic behind its functions and why its circuit is so complex.

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To celebrate the 45th anniversary of the Intel 8008 microprocessor today, I reverse engineered the chip's internal stack. Instead of normal binary counters, the chip uses "nonlinear feedback shift registers", generating pseudo-random counts. This unusual technique saves a few transistors; this was important in 1972 when every transistor was precious.

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I've reverse-engineered the ALU of the vintage 8008 microprocessor, using the die photos I took recently. It uses an interesting circuit, along with a carry-lookahead system for higher performance.

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I take a look inside the 74181 ALU chip. This chip performed arithmetic operations inside many minicomputers in the 1970s. It uses a variety of TTL gates, primarily AND-OR-INVERT logic, and I reverse-engineer how the interesting circuits it uses.
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