Reverse-engineering the vintage Intel 8087’s tangent algorithm: more than CORDIC

· Adafruit Industries Blog · Sept. 28, 2026, 1:51 p.m.
Summary
This blog post details Ken Shirriff's reverse-engineering of Intel's 8087 floating-point coprocessor, focusing on its tangent computation algorithm. The process included physically opening the chip and analyzing its micro-instructions, revealing deeper insights into the technology behind the 8087. It highlights a unique exploration of vintage computing hardware, showcasing innovative techniques for understanding complex algorithms.
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