Ferranti’s Ghost Tours The Chip Factory That Made The ULA

Former Ferranti Electric engineer [Martin Mallinson] recently posted a 1980s documentary on YouTube (see the video below the break). It shows in some detail the semiconductor plant at Gem Mill outside of Manchester UK, as seen through the eyes of the ghost of founder Dr. Sebastian Ferranti. This dramatic device seems a little silly at times, but the documentary still provides a very interesting look at the industry at the time.

The Gem Mill plant was one of the first semiconductor facilities, having begun operations in the 1950s by Ferranti. In 1959 they made the first European silicon diode, and went on to commercialize Uncommitted Logic Arrays (ULA) in the early 1980s. Most famously, Ferranti ULAs were used in many home computers of the day, such as the Sinclair ZX81 and ZX Spectrum, Acorn Electron, and the BBC Micro. Much of the factory tour in this documentary is depicting the ULA process, and they hint at an even more advanced technology being developed by the (unnamed) competition — an FPGA? CPLD?

In a series of events worthy of a mystery novel, Ferranti finally closed its doors in 1993 after acquiring a company that was involved with clandestine agencies and illegal arms sales (see Ferranti on Wikipedia). But through a series of acquisitions over the years, many of their products outlived the company and were available under the labels of future owners Plessey, Zetex, and finally Diodes, Inc. The Gem Mill facility was decommissioned in 2004 and in 2008 it was demolished and replaced by a housing estate.

Thanks to [Cogidubnus Rex] for bringing this video to our attention. A couple of other Ferranti documentaries of the same era are also included down below the break.

 

15 thoughts on “Ferranti’s Ghost Tours The Chip Factory That Made The ULA

  1. I worked for Ferranti (Cheadle Heath) in the 80’s up to the point they went bust. Business lesson kids, don’t get in bed with shady international arm dealers.

    Great technology company, terrible management, but that was British industry then.

    Although we used some of their chips in our Sonar systems, I was not aware of the plant. (People of a certain generation may think that is weird, but before the internet and Google it was amazing how much you did not know going on around you)

    Thanks for the nostalgia

  2. Thanks for this, I went for an meeting here in 1984 when the company I was working for was wanting some custom ULAs, I remember the factory tour looked like SciFi set at the time, its amazing how quickly things date.

    1. I was an apprentice at Ferranti, 1980s. Spent a short time at Gem Mill. Sadly I remember little about it; Most of my time was spent in Moston and Cheadle Heath. If I’d known they were making ULAs for the very machines I had at home, I might have tried to grab a few!

  3. A lot of UK plant still is run by Ferranti kit, several of the AGR power stations and apparently the McVities biscuit production line.

    The Ethernet cards we used had the MAC address configured via 3 physical dials and it picks the last 32 bits to use as the IP address, interesting approach!

  4. “and they hint at an even more advanced technology being developed by the (unnamed) competition — an FPGA? CPLD?”

    anyone know who this company was or what they were designing?

  5. ” In 1959 they made the first European silicon diode, and went on to commercialize Uncommitted Logic Arrays (ULA) in the early 1980s. ”

    Soon followed by the Recently-Divorced Logic Arrays.

    1. Although they also made 16 bit microprocessors the F100L for example. I knew them for good performance cheap transistor, DACS, voltage references. I also had an early version Digital Panel meter IC ??450 or something. It used fewer external parts than another DPM IC because it used Delta-sigma A-D conversion. I suspect Crystal bought the IP for that?

    1. I too managed to sneak out a design manual and some other bits and pieces. A reminder of the amazing time that we had with Ferranti back then having a world lead with the ULA

    1. My understanding is that the Ferranti ULA concept was ‘invented’ by the late Technical Director David Grundy while he was watching an Oldham Athletic soccer match. He always finished the story with the throwaway line that, “It was a very boring match”!
      The ULA may not have been unique as a ‘sea of gates’ customisable chip, but Ferranti’s CDI (Collector Diffusion Isolation) process was well-suited to the implementation in being able to provide Vcc and Ground contacts in every cell across the chip surface
      Commercially the Ferranti ULA enabled (and protected) many ground-breaking products of the time e.g. Acorn BBC and Sinclair home computers. It was an amazing time!

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