website/content/museum/compukit-uk-101.md

title, categories, types, origins, years, cpus, params

title	categories	types	origins	years	cpus	params
Compukit UK-101	Computers	Home Computer	United Kingdom	1979	6502	name image company company_name specs tabs photos adverts links comments oc_id source UK-101 /media/museum/photos/compukit_uk101_mainboard_s1.jpg /companies/compukit Compukit label value NAME UK-101 label value MANUFACTURER Compukit label value TYPE Home Computer label value ORIGIN United Kingdom label value YEAR 1979 label value BUILT IN LANGUAGE Microsoft BASIC label value KEYBOARD Full stroke 50 keys label value CPU 6502 label value SPEED 1 MHz. (could be 'overclocked' at 2 MHz by modifying the clock divide circuit) label value CO-PROCESSOR None label value RAM 4 KB expandable to 8 KB on board label value VRAM 1 KB label value ROM 8 KB (Microsoft BASIC) + 2 KB monitor label value TEXT MODES 16 to 48 chars. x 16 lines label value GRAPHIC MODES None, but 128 graphic characters label value COLORS Monochrome label value SIZE / WEIGHT unknown label value I/O PORTS Tape recorder (at 300 baud) and printer ports label value BUILT IN MEDIA None label value POWER SUPPLY External AC transformer. Power regulation on board label value PERIPHERALS Supports all Ohio Scientific expansions label value PRICE £249 in kit form photos adverts links title subtitle text image IVAN'S SYSTEM Handmade wooden case topped by a metal tray /media/museum/photos/compukit_uk101_redcase_s2.jpg title subtitle text image RUNNING Boot-up screen Thanks to **Ivan Gleaves** /media/museum/photos/compukit_uk101_redcase2running_s1.jpg title subtitle text image INSIDE **(1)** UHF TV modulator. The UK-101, in its original version, could be connected only to a TV set.\ **(2)** Normally, the power regulator took place here\ **(3)** RAM chips (2104). the board is here equipped with 6 KB of RAM\ **(4)** 6502 processor. Notice at its right hand side two empty sochets used for the optional RS232 interface\ **(5)** 40-pin expansion socket\ **(6)** 6850 ACIA (Asynchronous Communication Interface Adapter)\ **(7)** 2 KB monitor ROM\ **(8)** 8 KB BASIC ROMs\ **(9)** Character generator ROM /media/museum/photos/compukit_uk101_redcase2inside_s1.jpg title subtitle text image MAINBOARD CLOSE-UP /media/museum/photos/compukit_uk101_mainboard_s2.jpg title subtitle text image REAR SIDE The fan and the tape recorder In/Out sockets /media/museum/photos/compukit_uk101_redcaserear_s1.jpg title subtitle text image ANOTHER RED CASE /media/museum/photos/compukit_uk101_redcase_s1.jpg title subtitle text image INSIDE This model features a RAM expansion card fixed on top of the main board. /media/museum/photos/compukit_uk101_redcaseinside_s1.jpg title subtitle text image UK101 MANUAL The manual gives constructional details, along with a technical description of the system and a reference description of the Microsoft BASIC language.\ The cassette tape holds the Extended Monitor as well as some sample games in BASIC. /media/museum/photos/compukit_uk101_manual_s1.jpg title subtitle text image UK ADVERT (DEC. 1979) Thanks to David Wilson for this picture /media/museum/pubs/compukit_uk101_pub_dec1979.jpg title subtitle text image £149 IN JUNE 1981 /media/museum/pubs/compukit_uk101_advjune81.jpg title subtitle text image £99 IN JANUARY 1982 /media/museum/pubs/compukit_uk101_advlastsales.jpg title url text UK101 Hardware Page http://home.micros.users.btopenworld.com/uk101/uk101.html How to build your own micro UK101! title url text Collection of UK101 programs (zip file) http://www.cse.dmu.ac.uk/~mward/martin/software/UK101-tapes.zip UK101 BASIC and assembler programs, recovered from tapes by Martin Ward author date text Stephen Cole (United Kingdom) Thursday 9th March 2023 Myself and serveral others in the Reading UK area had these in the early 80''s, and did the ram, video, cassette hardware hacks etc. author date text Peter Jones (United Kingdom) Friday 17th February 2023 @Terry Brown. We might have met. I bought an Exidy Sorcerer from Chris in 1978 and visited the Barnet shop quite a lot after that. I remember sitting outside having a beer with Chris and he was saying that he was considering setting up a pirate TV station. author date text Mario (Switzerland) Sunday 14th February 2021 Hi! Is there anyone out there who owns a working Compukit UK101 computer and would be willing to sell it? Thanks author date text Con Cunningham (Ireland) Wednesday 22nd July 2020 @Terry - Chris Carey opened radio station in Dublin, and the folk involved set up a sales and support organisation run out of a very decrepit basement in Dublin city centre. I was studying CS in Trinity at the time, and used to work part-time for them, either soldering kits for purchasers, or fixing those that didn''t work. (Almost always bent pins on the ICs)\ Those were some very happy days :-) author date text terry brown (United Kingdom) Thursday 23rd January 2020 I worked at Comp shop New Barnet , selling these and helping pack them , its was run by Chris Carey great days - i then build and developed software for Nascom , i was 14 at the time author date text Martin Ward Thursday 28th August 2014 Change the dollar sign to a hash sign in the URL''s below author date text Martin Ward Thursday 28th August 2014 If you have old software on cassette tape, which no longer loads, I have written a program which analyses the tape (saved as a wav file) and extracts the data: http://www.gkc.org.uk/martin/software/$CUTS My collection of Compukit UK101 software can be downloaded from here: http://www.gkc.org.uk/martin/software/$UK101 author date text Holger Palmroth (Germany) Wednesday 15th January 2014 The URL of the DIY UK-101 has changed quite a while ago. Here is the current one: http://searle.hostei.com/grant/uk101/uk101.html author date text Stephen Burgoyne Coulson (UK) Saturday 22nd November 2008 Watford Electronics? That makes sense - as I rememeber buying and installing a new monitor ROM around 1981 is and I have the distinct memory that it was named WEMON. Needed a bit of board mod, trace cutting, extra wire. Provided full cursor control (you could print strings that would contain control characters to move your cursor around on the screen) and some other clever things that I can''t remember now. author date text Simon Anthony (UK) Sunday 5th December 2004 Mine still works... A friend at the BBC made his work in colour... I wrote a space invaders game - four aliens... miss one and the 'bullet' got stuck in the code.... It crashed, list it and there was the bullet. (memory mapping the screen does that :>) BBC VT shift 1 was UK101 - Shift two was the Nascom machine I think. Shift one moved on to the BBC micro - then the Archimedes. Shift two went the IBM clone way. I was shift one - I loved my Risc OS - still use it whenever I can. Code is on my (aged) homepage. 802 url date https://web.archive.org/web/20230602120509/http://www.old-computers.com/museum/computer.asp?c=802 2023-06-02

Made in the UK by Compukit in New Barnet, North London, the UK-101 was originally a copy of the Ohio Scientific Superboard II. Two years and various legal battles later the UK-101 became, technically, behind its erstwhile rival.

You could buy the UK101 as a kit or as ready made for an extra fee. The kit came in a cardboard briefcase, in which there were anti-static tubes containing the 65+ ICs, a box of IC sockets, and bags containing passives (mainly 0.1uF ceramic decoupling capacitors) and keyboard bits (the keyboard switches were soldered directly to the PCB).

The UK101 came with a transformer in a plastic case, which was rectified and regulated down to +5, the regulator's heatsink was far too small and it would run very very hot, causing the RF modulator to drift channel. Many people relocated the regulator off-board onto a bigger heatsink to solve both problems.

It came with an A4-size book authored by Dr. A.A. Berk, covering assembly, trouble-shooting, and circuit diagrams with descriptions.

The UK101 was based around the 6502 processor. On top of ASCII characters, 128 graphic characters were available in ROM. The RAM memory was expandable from 4 KB to 8 KB on board, or 40 KB with an expansion board.

At the time, The UK101 was heavily supported by Watford Electronics in the UK, and by various electronics magazines who published circuits. There were many user groups and plenty of software available. It was thus possible to upgrade this machine beyond all recognision !
Several cases were also made and sold by a number of manufacturers.

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Contributors: Paul Mansfield

John reports to us:
There were 3 monitor chips available, this being the 8k rom. The only one I can remember the name of was the Cegmon, the latest in the series.
The 40 pin expansion slot offered some inpressive (for the time) abilites. Mine had a sound card in it but I also saw systems with colour, hard drives and 5.25 floppy systems.

Some boards had links in them in place of the two sockets on your picture. These needed to be removed if you wanted to use the 40 pin expansion and a couple of 8T28s (buffer chips) put in their place. Other expansions I saw included a 'graphics' chip that could be switched in using software. A small pigiback board replaced the Normal character chip (which is the horizontal one in your picture) with the graphics rom and normal character rom slotted into it. This gave 256 additional characters, and since the replacement rom was an Eprom these new characters could be anything.

Programming was via Microsoft 8k Basic and involved a lot of Poke instructions to get it to do anything much. Overclocking was a breeze, but you had to get it right otherwise the screen divided into 4!

Martin Ward adds:
You could upgrade the graphics RAM by "piggkbacking" two new RAM chips on top of the existing chips, with one pin sticking out sideways which had a flying lead soldered to it. This gave you 48 characters x 32 lines.
The tape recorder could also be "overclocked" to 600 or even 1200 baud!
RAM cost about £10 per K (£5 per 1KB x 4bit chip).

Dick Greening reports:
An interesting story is that one of the BBC engineers rewrote the garbage collection routine (in the Microsoft Basic 4 Rom I thing it was,) only to find later that somehow Microsoft had incorporated his routine in their new version of Basic. He was able to prove it was his program as he had encrypted his name in the program! Sound a familiar story!

We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.