Chip off the old block

Standalone sales of the Z80 CPU have finally been discontinued after 48 years. David Crookes looks back on a chip with a staggering impact

- David Crookes

When you consider the list of machines that have made use of Zilog’s Z80 microprocessor chip, it reads like a computing equivalent of Who’s Who. Having burst onto the tech scene on the back of a 1976 advert that pitted the Z80 squarely against Intel’s 8080A in a so-called “Battle of the 80s”, Zilog’s single chip ended up being used in Sinclair’s ZX80, ZX81 and ZX Spectrum, Amstrad’s CPC and PCW ranges, the TRS-80, the Osborne-1, a host of early Sega consoles and many more machines besides.

You’ll find it in the Amstrad NC-100 and NC-200, the TRS-800 Model 100 and Sinclair’s Cambridge Z88. You’ll spot it inside graphing calculators made by Texas Instruments and Amstrad’s ill-fated E-mailer telephone. There was a Zilog Z80 chip inside the Commodore 128, which allowed it to run the operating system CP/M. This OS came to be very closely associated with the Z80 and it meant gems such as the database management program dBase and the word processor WordStar could be used across platforms.

The Z80 chip has also powered lots of obscure computers, from the Mattel Aquarius to the Dick Smith Super-80. In fact, it was so widely used that practically anyone growing up in the 1970s, 1980s and even 1990s would have been in contact with a Z80-based machine at some point. And if they weren’t, then perhaps they got to grips with a computer that contained a compatible clone. There were plenty of those, too.

With all that in mind, it’s been sad to learn that Zilog stopped accepting orders for the standalone Z80 CPU on 14 June this year, putting an end to 48 years of production. After all, the chip that powered the Pac-Man arcade game has proven perfect for devices which haven’t needed immense amounts of power. And, while Zilog is going to continue manufacturing the eZ80 8-bit microprocessor introduced in 2001 as an updated version of the Z80, it still feels as if the tissues need to be brought out in mourning for an old, departed friend.