Hardware Podcasts

An Interview With Bil Herd - Zany Z80 Zygology

The Amp Hour · 29 Oct 2014 · 2h 01m · Episode 222

What this episode covers

Bil Herd, a recovering Commodore engineer, recounts the chaotic development of the Commodore 128, explaining how they integrated a Z80 processor to ensure CPM compatibility and bypass TI interference. He details the extreme time pressures of the 1985 CES cycle, describing how the team used 'dirty design' tricks like phase-locked clocks and hand-wired jumpers to fix metastability and signal reflection issues in custom NMOS chips. Herd also discusses the company's flat, high-stress culture under Jack Tramiel, the transition from hand-taped layouts to early CAD, and the eventual cancellation of the Commodore LCD laptop project.

Most relevant to

established companies

Topics

Mentioned

Companies
MOS Technology
Products
Commodore 128, Commodore 64, TI-99/4A, Commodore LCD, Radio Shack Model 100
Chips
Z80, VIC chip, 6502
Also
Jack Tramiel, Chuck Peddle, Steve Jobs, CPM, Hackaday

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