Rostronics Advert - July 1980

Rostronics, of Wandsworth High Street in London, had been supplying printers, books, software, its own memory kits for the TRS-80, Apple II and the Exidy Sorceror, and 8" floppy disk drives for both the Exidy and the TRS-80 since at least 1979.

It had also been importing and selling the TRS-80 itself, before making an apparently significant leap at the beginning of 1980 when it started reselling an OEM version of Micromation's Z-Plus Microcomputer System - a system nicknamed the "coffin computer" thanks to its wooden casing, and which was aimed squarely at the business market, rather than domestic or small-office environment of the TRS-80.

Here, it's launching the System Z multi-user microcomputer system, also built by Micromation and which was announced at the West Coast Computer Fair in San Francisco in March 1980^[1].

The Z-Series range was one of the first multi-user microcomputers to offer individual CPU cards for each user, holding up to four cards each of which contained a Z80A processor and 64K of user RAM, all managed by a master board, also running a Z80A at 4MHz.

According to company president Ben Cooper, it was designed to overcome a significant issue at the time: how to give users acccess to peripherals like hard-disk storage and printers - which were often the most expensive components in a micro system - as efficiently and fully as possible.

An earlier advert from Rostronics showing it as a reseller of books, software and peripherals. From Practical Computing, December 1979

Whilst the master board ran the multi-user version of CP/M - M/PM - each user card ran conventional CP/M, giving access to thousands of application programs. There was also a version of Pascal-M available, so that OEM resellers could tailor the system for their users' particular needs.

The system also shipped with an S-100 I/O board which managed the serial connections to the four user terminals over RS-232, as well as providing two parallel output ports for printers. It also came with two 8" floppy drives giving 1MB of storage, and had the option of a Shugart SA4000 hard disk, with 28MB capacity.

There's no price on this advert, but at launch in the US a two-user System Z retailed for $12,995, which is around £61,200 in 2026 money, with additional users costing $995 (£4,690) each.