Miles Gordon Technology

Miles Gordon Technology, known as MGT, was a small British company, initially specialising in high-quality add-ons for the Sinclair ZX Spectrum home computer. It was founded in June 1986 in Cambridge, England by Alan Miles and Bruce Gordon, former employees of Sinclair Research, after Sinclair sold the rights for the Spectrum to Amstrad. They moved to Swansea, Wales, in May 1989, became a public company in July 1989 and went into receivership in June 1990.

As the ZX Spectrum became hugely popular, the lack of a mass storage system became a problem for more serious users. While Sinclair's response, the ZX Interface 1 and ZX Microdrive, was very cheap and technologically innovative, it was also rather limited. Many companies developed interfaces to connect floppy disk drives to the ZX Spectrum, one of the most successful being the Opus Discovery; however, these were all to some degree incompatible with Sinclair's system.

MGT's approach was different. It produced two different floppy-disk interfaces for the Spectrum, first the DISCiPLE (marketed by Rockfort Products) and later the cut-down +D interface (marketed by MGT themselves). Both, however, shared certain features:

The latter generated a non-maskable interrupt, freezing any software running on the Spectrum and allowing it to be saved to disk. This made it simple to store tape-based games on disk, to take screenshots and to enter cheat codes. A duplicate expansion connector at the back allowed other peripherals to be daisy chained, although the complexity of the DISCiPLE meant that many would not work correctly.

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