website/content/museum/sinclair-mk-14.md

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

title	categories	types	origins	years	cpus	params
Sinclair MK 14	Computers	Home Computer	United Kingdom	1978	National Semiconductor SC	name image company company_name specs tabs forum_thread photos adverts links videos oc_id source MK 14 /media/museum/photos/sinclair_mk14_system_1.jpg /companies/sinclair Sinclair label value NAME MK 14 label value MANUFACTURER Sinclair label value TYPE Home Computer label value ORIGIN United Kingdom label value YEAR 1978 label value END OF PRODUCTION Unknown label value BUILT IN LANGUAGE Basic ROM monitor label value KEYBOARD Sensitive and later mechanical hexadecimal 21key label value CPU National Semiconductor SC/MP II label value SPEED 4.4 MHz label value CO-PROCESSOR Optional 8154 I/O RAM chip (not really a coprocessor..) label value RAM 128 Bytes expandable to 640 bytes on board (not Kbytes!) label value VRAM No video as standard label value ROM 512 bytes, holds the monitor label value TEXT MODES 1 line of 8 or 9 digits label value GRAPHIC MODES None label value COLORS Red! label value SOUND None label value SIZE / WEIGHT 11.5 (W) x 25.5 (H) cm label value I/O PORTS I/O lines, external keyboard label value BUILT IN MEDIA None label value POWER SUPPLY External AC transformer. Built in 5v cc regulator label value PERIPHERALS RAM and ROM cards, tape recorder card, video,... label value PRICE £39.99 photos adverts links videos 937 title subtitle text image FLAT KEYBOARD V.1 The first versions of the MK-14 were equipped with a cheap membrane keyboard. This version doesn't have neither the second 128-byte RAM chip nor the I/O chip. Thanks to Fabrice Siravo /media/museum/photos/sinclair_mk14_system_3.jpg title subtitle text image FLAT KEYBOARD V.2 Another flat keyboard version. Special thanks to **Chris Rowland** who donated us this boxed MK-14 version. /media/museum/photos/sinclair_mk14_system_s3.jpg title subtitle text image MECHANICAL KEYBOARD VERSION Sinclair MK-14, the computing power on your hand! /media/museum/photos/sinclair_mk14_system_2.jpg title subtitle text image MECHANICAL KEYBOARD VERSION www.homecomputermuseum.nl /media/museum/photos/sinclair_mk14_2%5B1%5D.jpg title subtitle text image REAR VIEW /media/museum/photos/sinclair_mk14_rear_1.jpg title subtitle text image SOLDER SIDE Notice the issue number IV /media/museum/photos/sinclair_mk14_solderside_1.jpg title subtitle text image KEYBOARD CLOSE-UP The keyboard is composed of 16 hexadecimal keys and 4 function keys:\ **[TE]** allows to enter a new hex value at the current address\ **[GO]** to run a program in memory from the current address\ **[M]** Increments the address counter and displays the next address location\ **[AB]** allows to enter a new address value which becomes the current address /media/museum/photos/sinclair_mk14_keyboard_1.jpg title subtitle text image PROCESSOR National Semiconductors introduced the SC/MP processor in April 1976. SC/MP means **S**mall **C**osteffective **M**icro **P**rocessor.\ At the time, it was the cheapest 8-bit processor. /media/museum/photos/sinclair_mk14_processor_1.jpg title subtitle text image DISPLAY The calculator display featured nine 7-segment digits. However, 8 of them were used on the MK-14 /media/museum/photos/sinclair_mk14_display_1.jpg title subtitle text image RUNNING /media/museum/photos/sinclair_mk14_display_s1.jpg title subtitle text image I/O CHIP This I/O chip (NS 8154) allowed 16 additional I/O lines to be used. It also contained 128 bytes of RAM. /media/museum/photos/sinclair_mk14_iochip_1.jpg title subtitle text image TRAINING MANUAL /media/museum/photos/sinclair_mk14_manual_s1.jpg title subtitle text image THE BOX /media/museum/photos/sinclair_mk14_box_s1.jpg title subtitle text image SCHEMATIC DIAGRAM Schematic diagram of the MK-14 Issue 2 Thanks to **Graham Galbraith** /media/museum/photos/sinclair_mk14_diagram_s1.jpg title subtitle text image FRENCH ADVERT (1978) /media/museum/pubs/sinclair_mk14_pub_1.jpg title subtitle text image UK ADVERT (FEB. 1980) Thanks to David Wilson for this picture /media/museum/pubs/sinclair_mk14_uk-pub_1.jpg title url text MK14 v2.0 - How I recreated my first computer. http://mymk14.co.uk/ Lot of content here ! title url text The Sinclair / Science of Cambridge MK14 Web Site http://mymk14.co.uk/paulRobson/index.htm History, emulators, tech info, source code, ... title url text Wikipedia page http://en.wikipedia.org/wiki/MK14 title url text Science of Cambridge (Sinclair) Mk.14 Micro Computer presentation https://www.youtube.com/watch?v=ZCm9L94S-fY Length: 5m 43s 961 url date https://web.archive.org/web/20230224111139/http://www.old-computers.com/museum/computer.asp?c=961 2023-02-24

The MK-14 was the first computer made by the Sinclair company (at the time called Science of Cambridge because the Sinclair name was used by another company).

The MK-14 was a training board sold in kit form for £39.95 and featuring a National Semiconductor SC/MP 8-bit processor, 256 bytes of RAM, 512 bytes of ROM holding a monitor, calculator keyboard and display, and some I/O ports.

In fact, Clive Sinclair was not very enthusiastic about a personal computer project. The MK-14 project was thus managed by Chris Curry and produced by National Semiconductor. As the system was five times cheaper than its closest competitor, the Compukit UK-101, about 20,000 MK-14 boards were sold in the U.K.

Chris Curry, who believed much more than Clive Sinclair in the future of such computers, left the company in 1978, founded Acorn Computers with Herman Hauser and built its fist computer kit, the System 1. A few months later, Clive Sinclair decided that computers were a good way to raise money and started a new project: a complete computer for less than £100.

Meantime, the MK-14 grew into a modular system and several additional cards allowed expansion of the system: cassette interface, text and graphics video module and Eprom programmer. 128 and 256 bytes RAM expansion chips could also be added up to a total of 640 bytes. Yes...640 BYTES...

The version pictured here is an issue 4 with a better mechanical keyboard than the 'sensitive' one of the earlier versions, as well as optional RAM and I/O chips. At least 5 issues were sold. The issue 5 featured additional I/O ports.

If the MK-14 had not been launched, Clive Sinclair probably wouldn't have thought of his ZX-80 so soon, and the global personal computer scene would have been very different.

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David Rayner adds:
The Keyboard was unreliable I bought a separate keyboard. There was no storage so every program had to typed in machine code every time. (I never had the tape interface).
The first test program was jmp 0000 (3 bytes). There was a shoot the duck game (a character flying acroos the calculator style display). By connecting a speaker you play "music". It was actually quite fun.

Mark Dodd reports to us:
We used these things with a ROM burner in an Australian college for our Microprocessor training.
The smarter ones in the classes wrote programs that rewrote themselves as they went.