login
Tag: ALU
Inside the vintage 74181 ALU chip
Ken Shirriff writes: The 74181 ALU (arithmetic/logic unit) chip powered many of the minicomputers of the 1970s: it provided fast 4-bit arithmetic and logic functions, and could be combined to handle larger words, making it a key part of many CPUs. Inside the vintage 74181 ALU chip -...
Continue Reading
Reverse-engineering the ALU of 8008 microprocessor
Ken Shirriff has written an article on reverse engineering the ALU of the 8008 microprocessor: A computer’s arithmetic-logic unit (ALU) is the heart of the processor, performing arithmetic and logic operations on data. If you’ve studied digital logic, you’ve probably learned...
Continue Reading
Inside the 74181 ALU chip: die photos and reverse engineering
A detailed die photos and reverse engineering of the 74181 ALU chip by Ken Shirriff: What’s inside a TTL chip? To find out, I opened up a 74181 ALU chip, took high-resolution die photos, and reverse-engineered the chip.1 Inside I found several types of gates, implemented with...
Continue Reading
Inside the ALU of the first ARM microprocessor
Dave @ daveshacks.blogspot.co.uk takes a look inside the first ARM microprocessor and explains it's design. With that in mind I embarked on my own attempt to reverse-engineer parts of the armv1. Some background knowledge of the processor's architecture is helpful, and googling for...
Continue Reading
