The QL was aimed at the serious home user and professional and executive users markets from small to medium-sized businesses and higher educational establishments, but failed to achieve commercial success.[6]
The QL was conceived in 1981 under the code name ZX83, as a portable computer for business users, with a built-in ultra-thin flat-screen CRT display similar to the later TV80 pocket TV, printer and modem. As development progressed it eventually became clear that the portability features were over-ambitious and the specification was reduced to a conventional desktop configuration.[8][9]
The electronics were primarily designed by David Karlin, who joined Sinclair Research in summer 1982. The industrial design was done by Rick Dickinson, who already designed the ZX81 and ZX Spectrum range of products.
Sinclair had commissioned GST Computer Systems to produce the operating system for the machine, but switched to Domesdos, developed by Tony Tebby as an in-house alternative, before launch. GST's OS, designed by Tim Ward, was later made available as 68K/OS, in the form of an add-on ROM card.[11][12] The tools developed by GST for the QL would later be used on the Atari ST, where GST object format became standard.
Launch
Sinclair QL ROM "dongle" – needed to expand the internal 32KB ROM to 48KB in early QLs
At the time of the rushed launch, on 12 January 1984, the QL was far from being ready for production—there being no complete working prototype in existence. Although Sinclair started taking orders immediately, promising delivery within 28 days, first customer deliveries only started, slowly, in April. This provoked criticism of the company and the attention of the Advertising Standards Authority.[8]
Because of its premature launch, the QL was plagued by a number of problems from the start. Early production QLs were shipped with preliminary versions of firmware containing numerous bugs, mainly in SuperBASIC. Part of the firmware was held on an external 16KiB ROM cartridge also known as the "kludge" or "dongle", until the QL was redesigned to accommodate the necessary 48KiB of ROM internally, instead of the 32KiB initially specified.[8]
The QL also suffered from reliability problems of its Microdrives. These problems were later rectified, by Sinclair engineers, especially on Samsung produced models, as well as by aftermarket firms such as Adman Services and TF Services, to the point where several QL users report the Samsung Microdrives in particular working perfectly even after almost 17 years of service; but in any case too late to redeem the negative image they had already created.[citation needed]
Reception
Although the computer was hyped as being advanced for its time, and relatively cheap, it failed to sell well, and UK production was suspended in 1985, due to lack of demand. After Amstrad acquired Sinclair's computer products lines in April 1986, the QL was officially discontinued.
Apart from its reliability issues, the target business market was becoming wedded to the IBM PC platform, whilst the majority of ZX Spectrum owners were uninterested in upgrading to a machine which had a minimal library of games (with only about 70 titles,[13] compared to the Spectrum's more than 4700[14]). Sinclair's persistence with the non-standard Microdrive and uncomfortable keyboard did not endear it to the business market. Sinclair later maintained that the Microdrive was "a marvellous approach", also claiming that he had really wanted to base the QL on the Z80, that others in the company had persuaded him to use the 68000, and that "there was nothing you could do on the 68000 that you couldn't do on the Z80".[15] Software publishers were also reluctant to support the QL because Microdrive cartridges were the only available distribution medium for the QL, and the unfavourable pricing of the medium (production costs being given as over six times that of compact cassette) impacted profitability and made QL-based products uncompetitive.[16]
Dedicated magazines were published for the system, such as QL World (published from 1985 to 1994),[17]QL User (published from 1984 to 1985),[18] or QL Today (published from 1996 to 2013).[19]
Design
Motorola 68008 and ZX8301 on the QL's PCB
Based on a Motorola 68008 processor clocked at 7.5MHz, the QL included 128 KiB of RAM, which is officially expandable to 640KiB and in practice, 896KB.[20]
It can be connected to a monitor or TV for display. Sinclair recommended the "SINCLAIR VISION-QL" RGB monitor for usage with the QL.[21] When connected to a normally-adjusted TV or monitor, the QL's video output overscans horizontally. This is reputed to have been due to the timing constants in the ZX8301 chip being optimised for the flat-screen CRT display originally intended for the QL.[22]
Sinclair QL color palette
256 × 256
512 × 256
black
black
blue
red
red
magenta
green
green
cyan
yellow
white
white
Two video modes are available, 256 × 256 pixels with 8 primary RGB colours and per-pixel flashing, or 512 × 256 pixels with four colours: black, red, green and white.[20] Both screen modes use a 32KiB framebuffer in main memory. The hardware is capable of switching between two different areas of memory for the frame buffer, thus allowing double buffering. However, this would use 64KB of the standard machine's 128KiB of RAM and there is no support for this feature in the QL's original firmware. The alternative and improved operating system Minerva provides full support for the second frame buffer.
QL internals (with Minerva ROM fitted)
Internally, the QL comprises the CPU, two ULAs (ZX8301 "Master Chip" and ZX8302 "Peripheral Chip") and an Intel 8049[20]microcontroller known as the IPC, or "Intelligent Peripheral Controller".
QL rear view
The ZX8301 implements the video display generator and also provides DRAM refresh. The ZX8302 interfaces to the RS-232 ports (transmit only) Microdrives, QLAN ports, real-time clock and the 8049 via a synchronous serial link. The 8049 included at a late stage in the QL's design (the ZX8302 originally being intended to perform its functions[8]) runs at 11MHz and acts as a keyboard/joystick interface, RS-232 receive buffer and audio generator.[23][20]
When comparing technical specifications among microcomputers in the traditional sense of the term, the QL qualifies as the fastest for having a 15MHz clock that alternates between Motorola's 68008 & Intel's 8049.
Bundled Psion application software on Microdrive cartridges
Two built-in Microdrive tape-loop cartridge drives provide mass storage, in place of the more expensive floppy disk drives found on similar systems of the era. Microdrives had been introduced for the ZX Spectrum in July 1983, although the QL uses a different logical tape format.
Interfaces include an expansion slot, ROM cartridge socket, dual RS-232 ports, proprietary QLAN local area network ports, dual joystick ports and an external Microdrive bus. The QL uses British Telecom type 631W plugs of similar design to British telephone sockets for serial cables except for QLs built by Samsung for export markets, which have DE-9 sockets. Joysticks connect to the QL with similar type 630W plugs.
Physically, the QL is the same black colour as the preceding ZX81 and ZX Spectrum, but introduced a new angular styling theme and keyboard design which would later be seen in the ZX Spectrum+.
According to Sinclair Research, it was the first mass-market computer with an OS featuring pre-emptive multitasking and a Windows-style operating system, predating Microsoft Windows 95 by 11 years, and Apple Computer Macintosh launch by a month.[25]
The result of a three-year collaboration between Sinclair Research, ICL and British Telecom, the One Per Desk adds a telephone handset at one end of the keyboard, and rudimentary Computer-Telephony Integration (CTI) software.[26] This machine interested a number of high-profile business customers, including certain divisions of the former UK Customs and Excise Department, but its success was generally limited. In the late 1980s they were used in bingo halls to allow a country-wide networked bingo game.[27]
Linux
Linus Torvalds has attributed his eventually developing the Linux kernel, likewise having pre-emptive multitasking, in part to having owned a Sinclair QL in the 1980s. Because of the lack of support, particularly in his native Finland, Torvalds became used to writing his own software rather than relying on programs written by others.[28] In part, his frustration with Minix, on the Sinclair,[29] led, years later, to his purchase of a more standard IBM PC compatible on which he would develop Linux. In Just for Fun, Torvalds wrote, "Back in 1987, one of the selling points of the QL was that it looked cool", because it was "entirely matte black, with a black keyboard" and was "fairly angular". He also wrote he bought a floppy controller so he could stop using microdrives, but the floppy controller driver was bad, so he wrote his own. Bugs in the operating system, or discrepancies with the documentation, that made his software not work properly, got him interested in operating systems. "Like any good computer purist raised on a 68008 chip," Torvalds "despised PCs", but decided in autumn 1990 to purchase a 386 custom-made IBM PC compatible, which he did in January 1991.[30]
After Amstrad abandoned the QL in 1986, several companies previously involved in the QL peripherals market stepped in to fill the void. These included CST and DanSoft, creators of the Thor line of compatible systems; Miracle Systems, creator of the Gold Card and Super Gold Card processor/memory upgrade cards and the QXL PC-based hardware emulator; and Qubbesoft, with the Aurora, the first replacement QL mainboard, with enhanced graphics modes.[23]
In the late 1990s, two partly QL-compatible motherboards named Q40 and Q60 (collectively referred to as Qx0) were designed by Peter Graf and marketed by D&D Systems. The Q40 and Q60, based on the Motorola 68040 and 68060CPUs respectively, are much more powerful than the original QL and have the ability among other things (such as multimedia, high resolution graphics, Ethernet networking etc.) to run the Linux operating system.[31]
In 2013 Peter Graf announced that he was working on the Q68, a FPGA based QL compatible single board computer. The Q68 was first presented to the public in April 2014 and became available in autumn 2017. It is produced and marketed by Derek Stewart (of former D&D Systems).[32]
Hardware add-ons such as new developments like the QL-SD (designed by Peter Graf)[33] and reengineered or even expanded 1990s designs such as QubIDE interfaces (by José Leandro Novellón).[34] Trump, Gold & Super Gold Cards (by Tetroid) are still being produced for the original QL.[35]
RWAP Software supplies various hardware and software upgrades and spare parts.
Operating systems
Patched or reengineered versions of QDOS were produced, most notably Minerva which gradually evolved into a completely rewritten operating system, offering improved speed, with multitasking SuperBASIC interpreters. Tony Tebby went on to produce another updated operating system, SMSQ/E, which has continued to be developed for the Sinclair QL and emulators, offering many more features.[36]
Emulators, virtual QLs and distributions
Several emulators and virtual QLs became available over time, of which Q-emuLator (Windows/Mac),[37] QPC2 (Windows),[38] SMSQmulator (Java),[39] ZEsarUX (Windows/Mac/Linux)[40] and sQLux (Windows/Mac/Linux)[41] are actively maintained.
Several distributions of emulators, applications and information have been produced, of which Black Phoenix[42] and QL/E[43] are the most actively maintained.
The ZX Spectrum is an 8-bit home computer, developed by UK company Sinclair Research, and first released in 1982. It is one of the most influential computers ever made, and it is also one of the best selling computers ever, with over five million units sold.
Psion PLC was a designer and manufacturer of mobile handheld computers for commercial and industrial uses. The company was headquartered in London, England, with major operations in Mississauga, Ontario, Canada, and other company offices in Europe, the United States, Asia, Latin America, and the Middle East. It was a public company listed on the London Stock Exchange and was once a constituent of the FTSE 100 Index.
The SAM Coupé is an 8-bit British home computer manufactured by Miles Gordon Technology (MGT), based in Swansea in the United Kingdom and released in December 1989.
Sinclair BASIC is a dialect of the programming language BASIC used in the 8-bit home computers from Sinclair Research, Timex Sinclair and Amstrad. The Sinclair BASIC interpreter was written by Nine Tiles Networks Ltd.
Loki was the code name for a cancelled home computer developed at Sinclair Research during the mid-1980s. The name came from the Norse god Loki, god of mischief and thieves. Loki was based on the ZX Spectrum, but intended to rival the Amiga for video games.
The ZX Interface 1, launched in 1983, was a peripheral from Sinclair Research for its ZX Spectrum home computer. Originally intended as a local area network interface for use in school classrooms, it was revised before launch to also act as the controller for up to eight ZX Microdrive high-speed tape-loop cartridge drives. It also included a DE-9 RS-232 interface capable of operating at up to 19.2 kbit/s. At hardware level it was fundamentally a voltage adaptor, the serial protocol being implemented in software by bit-banging. This led to problems when receiving data, but not when transmitting.
SuperBASIC is an advanced variant of the BASIC programming language with many structured programming additions. It was developed at Sinclair Research by Jan Jones during the early 1980s.
Sinclair Research Ltd was a British consumer electronics company founded by Clive Sinclair in Cambridge. It was originally incorporated in 1973 as Westminster Mail Order Ltd, renamed Sinclair Instrument Ltd, then Science of Cambridge Ltd, then Sinclair Computers Ltd, and finally Sinclair Research Ltd. It remained dormant until 1976, when it was activated with the intention of continuing Sinclair's commercial work from his earlier company Sinclair Radionics, and adopted the name Sinclair Research in 1981.
The ZX Microdrive is a magnetic-tape data storage system launched in July 1983 by Sinclair Research for its ZX Spectrum home computer. It was proposed as a faster-loading alternative to the cassette and cheaper than a floppy disk, but it suffered from poor reliability and lower speed.
The ZX Interface 2 is a peripheral from Sinclair Research for its ZX Spectrum home computer released in September 1983. It has two joystick ports and a ROM cartridge slot, which offers instant loading times. The joystick ports are not compatible with the popular Kempston interface, and thus do not work with most Spectrum games released prior to the launch of the ZX Interface 2. In addition, the pass-through expansion bus provided was stripped, only allowing a ZX Printer to be attached.
Miracle Systems Ltd. were a manufacturer of personal computer peripherals and upgrades, specializing in the Sinclair QL, in the 1980s and early 1990s.
The One Per Desk, or OPD, was an innovative hybrid personal computer/telecommunications terminal based on the hardware of the Sinclair QL. The One Per Desk was built by International Computers Limited (ICL) and launched in the United Kingdom in 1984. It was the result of a collaborative project between ICL, Sinclair Research and British Telecom begun in 1983, originally intended to incorporate Sinclair's flat-screen CRT technology.
The CST Thor series of personal computers are Sinclair QL-compatible systems designed and produced by Cambridge Systems Technology during the late 1980s.
The ZX8301 is an Uncommitted Logic Array (ULA) integrated circuit designed for the Sinclair QL microcomputer. Also known as the "Master Chip", it provides a Video Display Generator, the division of a 15 MHz crystal to provide the 7.5 MHz system clock, ZX8302 register address decoder, DRAM refresh and bus controller. The ZX8301 is IC22 on the QL motherboard.
The ZX Spectrum's software library was very diverse. While the majority of the software produced for the system was video games, others included programming language implementations, Sinclair BASIC extensions, databases, word processors, spread sheets, drawing and painting tools, and 3D modelling tools.
The Q40 and Q60 are computer motherboards designed in the late 1990s, based on the Motorola 68040 and 68060 microprocessors respectively and intended to be partially compatible with the Sinclair QL microcomputer. Later these were sold as a fully assembled computer in an AT desktop case.
Touch Typist Typing Tutor is developed by Sector Software.
ZX Spectrum Next is an 8-bit home computer, initially released in 2017, which is compatible with software and hardware for the 1982 ZX Spectrum. It also has enhanced capabilities. It is intended to appeal to retrocomputing enthusiasts and to "encourage a new generation of bedroom coders", according to project member Jim Bagley.
↑ Dickinson, Rick (2007-07-16). "QL and Beyond". Flickr. Retrieved 2008-04-21.
↑ Feder, Barnaby J. (February 27, 1984). "British race is on in microcomputers". The New York Times. New York. Retrieved December 12, 2011. The QL is designed to be more powerful than the current bestseller, the International Business Machines Corporation's Personal Computer - comparable, in fact, to Apple Computer's new Macintosh.
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