[Donn] wanted know exactly what is going on inside of a processor so naturally he built a CPU out of TTL components. He had previously built a couple of versions of a computer based on the Z80 ...

The RC2014 is a modular 8-bit computer in which daughter cards containing RAM, ROM, serial interface, clock, and Z80 processor are ranged on a backplane board, allowing complete understanding of ...

It was called the Z80 SoftCard, and it was first released 43 years ago this month, on April 2, 1980. In an even more ironic twist, the product was made as an add-in card for the Apple II PC.

It was an 8-bit processor, not too dissimilar to the Zilog Z80 chip that I'd spent many years programming before getting a PC. There was a good reason for that similarity: Both processors were ...