In the very early days of the PC revolution the only way to have a computer was to build one, sometimes from a kit but often from scratch. For the young, impoverished hobbyist, leafing through the pages of Popular Electronics was difficult, knowing that the revolution was passing you by. And just like that, the days of homebrewing drew to a close, forced into irrelevance by commodity beige boxes. Computing for normies had arrived.
Many of the homebrewers-that-never-were are now looking back at this time with the powerful combination of nostalgia and disposable income, and projects such as [Ben Eater]’s scratch-built 6502 computer are set to scratch the old itch. The video below introduces not only the how-to part of building a computer from scratch, but the whys and wherefores as well. Instead of just showing us how to wire up a microprocessor and its supporting chips, [Ben] starts with the two most basic things: a 6502 and its datasheet. He shows what pins do what, which ones to make high, and which ones get forced low. Clocked with a custom 555 circuit that lets him single-step and monitored with an Arduino Mega-based logic analyzer, we get a complete look at the fetch and execute cycle of a simple, hard-wired program at the pin level.
This is one of those rare videos that was over too soon and left us looking for more. [Ben] promises a follow-up to add a ROM chip and a more complex program, and we can’t wait to see that. He’s selling kits so you can build along if you don’t already have the parts. There seems to be a lot of interest in 6502 builds lately, some more practical than others. Seems like a good time to hop on the bandwagon.