We've actually already seen one completely home-built 8-bit computer but, while Jake Eisenmann wasn't afraid to show off his creation, Kyle Hovey is actually inviting us along for the ride. The project started up last week when Hovey gathered his first batch of parts and a pair of books and started designing a simple 8-bit computer based on the SAP-1 architecture (SAP stands for Simple as Possible). The transistor-transistor logic (TTL) design is slowly coming together and every step of the process is being documented by Hovey on his blog so that others may follow along and learn from his experience (and, most likely, his mistakes as well).
Engadget
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gadgetsdaily, Watch as a DIY 8-bit computer comes together, learn something in the process