Zilog’s System 8000 Unix box

In January, 1983, I visited the USA and stopped in at Zilog in California with the South African Western Digital agent. (Not sure where they were in 1983, but in the San Franscisco area). He would become a Zilog System 8000 agent, and I bought the second and third System 8000 machines in South Africa (he bought the first). The second one I bought was for a radio paging system, the other for software development.

System 8000 Unix system

The Z8001 was used in Zilog’s Unix system with sixteen users and a hard drive, whereas the first PC was a toy that ran a version of a floppy disk operating system called CP/M that Microsoft bought — and the rest is history. Zilog’s second source, AMD defected to Intel and was embroiled in squabbles and court cases for years.

Your’s truly with the two Zilog System 8000s and one terminal connected to each system. The systems were interconnected via a serial cable using the Unix “cu” command — call up another system.

Ian and two System 8000 Unix systems

System 8000 Unix system opened

The front cover was removed to show the cards in the tower case. On top is a cartridge tape drive that could backup the whole hard drive, which is not something that is common these days (at low cost!).


The internal cards are shown below.

Z-BUS backplane

The Z-BUS backplane which we were given during our visit. For more info press here.

System 8000 internal cards

System 8000 CPU card

The CPU card has a Z8001 with three MMUs.

System 8000 disk controller

The disk controller had its own Z8001 processor.

System 8000 Memory card

That is what 512 kBytes of memory looked like in 1983. The multiplexing of the addresses for row and columns was done using discrete components.

System 8000 tape controller

The tape controller.

Interesting System 800 Site

Towards the end of 2015, we received an email requesting some higher resolution photos and if possible, any information regarding the System 8000. We still had the photos, but all documentation was sold with the box. If anyone would like to find out more on the System 8000, visit Oliver Lehmann's System 8000 site.

If you still have any System 8000 documentation or hardware, contact Oliver.