Collaborate Disseminate
Those of you with an interest in microcomputer history will know that there is a strong crossover between the path of electronic calculator evolution and the genesis of the integrated …read more Continue reading An ALU As A Desktop Calculator Has Stunning Style from Days Gone By
You can no longer buy a brand-new 74181, they’ve been out of production for years. All is not lost though, for [Dave’s Dev Lab] have created a facsimile of one on a printed circuit board, using modern single-gate 74-series chips.
Why on earth would you want an oversized replica of an outdated logic chip from nearly five decades ago, we hear you ask? The answer lies in education. If you were to embark on learning about the internals of a microprocessor by taking a modern example such as the one that powers the device on which you are reading this, …read more
Continue reading Huge 74181 is a Classic ALU You Can Actually Understand
You will all no doubt be familiar with the 74 series logic integrated circuits, they provide the glue logic for countless projects. If you look back through old listings of the series you’ll find alongside the familiar simple gates a host of now obsolete chips that reveal their roots in the pre-microprocessor computer industry of the late 1960s, implementing entire functions that would now be integrated.
One of the more famous of these devices is the 74181, a cascadable 4-bit arithmetic logic unit, or ALU. An ALU is the heart of a microprocessor, performing its operations. The 74181 appeared in …read more
[Ken Shirriff] is the gift that keeps on giving this new year. His latest is a reverse engineering of the 74181 Algorithmic Logic Unit (ALU). The great news is that the die image and complexity are both optimized for you to succeed at doing your own reverse engineering.
We have most recently seen [Ken] at work explaining his decapping and reverse engineering process at the Hackaday SuperCon followed soon after by his work on the 8008. That chip is crazy with complexity and a die-ogling noob (like several of us on the Hackaday crew) stands no chance of doing more …read more
