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Sinclair QL

Sinclair QL
('Quantum Leap')

Sinclair QL (70 KBytes)

The QL, which should've been Sinclair's 'quantum leap' into professional markets. Its two built-in Microdrives are right from the keyboard
(picture copyright by M.A.Grundke)

Specifications

Name Sinclair QL ('Quantum Leap')

Codenames
ZX83, because it was 'regarded [...] as combination of an enhanced Spectrum microcomputer' (=ZX82) 'with Interface 1, Interface 2 and two Microdrives' (from: QL servicemanual)
some call it ZX84, probably because of its release date. But perhaps that's been the name of another, secret project?

Made by Sinclair Research Ltd., Cambridge

Released January 1984

Serial-No.
right bottom:
D13-053077
left bottom:
SINCLAIR QL Professional Computer
no user serviceable parts inside.
use only approved AC adaptor.
Designed in Cambridge, England
by SINCLAIR Research Ltd.made in UK
© 1983 SINCLAIR Research Ltd.
Patent Applications, Design Applications

Board-info
sinclair QL
© 1984
ISS.5
sinclair
QL 1984 ISS.5
this ISSUE 5 board is one of the earlier board revisions, which originally came with only a 32K ROM and another one mounted 'pickaback' on it. It has later been upgraded to two ROMs (32K+16K), like ISSUE 6 and later boards. Another difference is that the 74LS03 (IC27) was, from ISSUE 6 on, replaced by a HAL16L8 (IC38). Furthermore, a 74LS00, which would normally reside at IC17, is missing. It was only fitted on EPROM versions of the board
also see the ISSUE 5 board overview

CPU Motorola MC68008 (48 pin DIP-version)
Intel 8049H111 microcontroller @11MHz
the MC68008 was probably the most 'exotic' of the MC680x0-series; externally, it has 20 bit address- and 8 bit data-bus, while internally processing at 32 bit (like all MC680x0). Due to its address-bus, the maximum of directly addressable RAM is 1 MByte
the MC68008 is code-compatible with its predecessor MC68000, and was intended as an alternative for cheap 8 bit board-designs

there was also a 52 pin PLCC version of the MC68008, with 22 bit address-bus (i.e. 4 MByte addressing range)

Speed 7.5 MHz

RAM ZX8301 (memory address decoding)
128 KBytes (16 pcs. 64Kx1)
this particular machine has been upgraded to 512 KBytes:
16 pcs. TMS4256-12NL (256Kx1)
in order to expand the machine's RAM without occupying the internal expansion port, the soldered 64Kx1 RAMs have been replaced by socketed 256Kx1 RAMs. For proper address selection, an additional PAL14L4 has been soldered pickaback onto IC21, and wired to some of the ZX8301's and IC20's pins

expandable to 4 MBytes via 3rd party expansions

32 KB of the internal RAM (no matter the amount) are used as video-RAM by the ZX8301, which is responsible for video refresh. Since CPU and ZX8301 access the internal RAM simultaneously, the CPU is occasionally being halted (since video refresh has higher priority). That's also the reason why onboard RAM expansions (e.g. replacing the onboard 64Kx1 chips) do not speed up RAM access times, while RAM connected to the expansion port can increase performance by up to 50%

ROM/ Native OS Sinclair QL.JM 0000 v1.03 (256Kx1)
Sinclair QL.JM 8000 v1.03 (128Kx1)
ROMs contain:
Sinclair QDOS ('QL disk operating system')
Sinclair SuperBASIC
QDOS is window-oriented and capable of preemptive multitasking. It also allows dynamic assignment of system resources (e.g. RAM/ ROM addresses) to programs or devices. SuperBASIC is a BASIC derivate, which allows structured programming. In addition to looping and branching in standard BASIC variants, SuperBASIC also allows the definition of functions and procedures
there have been several QL ROM-set revisions:
'FB', 'PM' (1984): early production ROMs with lots of bugs. Required an external cartridge ('dongle') for operation
'AH', 'JM' (1984): dongle not needed anymore, less bugs
'JS', 'JSU' (1985): lots of bugs fixed (but also with some new...). JSU was the 1st version developed for NTSC-machines
'MGx': localized ROM-sets for Germany (MGG), France (MGF), Spain (MGE), Sweden (MGS) and Italy (MGI). Additionally, 3rd party ROMs were available (e.g. with greek localization)

Keyboard/ Layout 65 keys/ US (QWERTY)
keyboard scanning done by the 8049 IPC
there was also a German localized QL with QWERTZ keyboard
according to Sinclair User, issue 39, Sinclair has also produced localized keyboards for other countries (e.g. Greece, France). Localized ROMs and software bundles do also exist

Graphics ZX8301 (video output & refresh)
Motorola MC1377P (RGB-to-NTSC/PAL encoding)
Text and graphics:
Max.Res.: 512x256 (4 colors)
Max. Colors: 8 (at 256x256, from a palette of 255)
Text: 85x25, 42x25, 64x25 and 40x25 character modes
this is a PAL-version; NTSC-versions (US-QLs with 'JSU' ROMs) do exist

Sound integrated loudspeaker
at fixed volume, controlled by the 8049 IPC
controllable duration, pitch/ pitch oscillation and distortion effects

Media
2x built-in Sinclair Microdrives
a Sinclair-invention and also called 'stringy floppy'
each drive controlled by a Ferranti 2G007A ULA
112.64 KB capacity/ tape (QL-format). Speed was 15 KB/ second
you could connect up to 8 drives to the QL
the media itself was a tiny (34x42mm) cartridge, with a small tape inside (but 5.6 meters in lenght!)

Microdrives were also available for the ZX Spectrum, although exchanging data with QL-drives was impossible

3.5" (720 KBytes, 250Kbit/s) drives via DD50 adaptor
harddisks with 7 MByte (Sinclair)/ up to 524 MByte (3rd party) via expansion port SCSI/ AT-bus adaptors

Input/ Output ZX8302 (controlling all I/O signals)
Motorola MC1488 (RS232 quad-line driver)
Motorola MC1489 (RS232 quad-line receiver)
2x QLAN (to connect directly to other QLs, 100 KBit/s)

8 pin round DIN video output (with both digital RGB- and composite signals)
RF-out (TV)
2x 6 pin RS232C (up to 19.2 KBit/s)
2x 6 pin CTL (for joysticks)
28 pin female edge cartridge connector
internal 64 pin expansion-bus (e.g. for DD50, memory expansions, harddisk controllers and CPU boards)

7 pin male edge connector (for additional Microdrives)
3 pin power-connector
has a reset switch

Miscellaneous
'QL' means 'Quantum Leap' - and indeed: the QL was one of the first 32-bit computers (only preceeded by the Apple Macintosh, which was released two weaks earlier). It came with impressive technical specifications, and an improved keyboard (in comparison to all other Sinclairs). The QL was Sinclair's first attempt to enter professional markets
The rare Motorola MC68008 CPU is quite interesting: the DIP version, used in the QL, has a 20 bit address- and an 8 bit data-bus. This made it easy to integrate into existing 8 bit board-designs. After all, cheap and efficient designs have always been a 'Sinclair philosphy'
People often complained about the Microdrives (although they were a cheap and efficient solution): the cartridges were said to frequently lose data...

The machine came with a software package, that included word-processor, spreadsheet-, database- and graphic application (see picture below)
The Sinclair QL was in many ways revolutionary, indeed, but it failed due to many problems in detail (buggy ROM-revisions, release problems). So when AMSTRAD overtook Sinclair's computer line, the QL was finally retired
After the QL was discontinued, several companies released unofficial QL-compatibles and clones (like the Sandy QXT 640 or CST Thor-series). These came with improved specifications (e.g. 68000/ 68020-CPUs, onboard disk controllers or improved graphic capabilities). But AMSTRAD would not allow official QL-successors to be built

'QL Quill' screenshot (30 KBytes)

Screenshot of QL Quill, the word-processor included in the machine's software package. It also contained QL Abacus (spreadsheet), QL Archive (database) and QL Easel (graphics). All programs came on Microdrive cassettes and were written by PSION Limited. The manual advises, by the way, to always work with microdrive backup copies - good recommendation, since the drives were known to be little reliable

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Sothius' Home - Museum - Sinclair - Sinclair QL - additional pictures

Name	Sinclair QL ('Quantum Leap')
Codenames	ZX83, because it was 'regarded [...] as combination of an enhanced Spectrum microcomputer' (=ZX82) 'with Interface 1, Interface 2 and two Microdrives' (from: QL servicemanual) some call it ZX84, probably because of its release date. But perhaps that's been the name of another, secret project?
Made by	Sinclair Research Ltd., Cambridge
Released	January 1984
Serial-No.	right bottom: D13-053077 left bottom: SINCLAIR QL Professional Computer no user serviceable parts inside. use only approved AC adaptor. Designed in Cambridge, England by SINCLAIR Research Ltd.made in UK © 1983 SINCLAIR Research Ltd. Patent Applications, Design Applications
Board-info	sinclair QL © 1984 ISS.5 sinclair QL 1984 ISS.5 this ISSUE 5 board is one of the earlier board revisions, which originally came with only a 32K ROM and another one mounted 'pickaback' on it. It has later been upgraded to two ROMs (32K+16K), like ISSUE 6 and later boards. Another difference is that the 74LS03 (IC27) was, from ISSUE 6 on, replaced by a HAL16L8 (IC38). Furthermore, a 74LS00, which would normally reside at IC17, is missing. It was only fitted on EPROM versions of the board also see the ISSUE 5 board overview
CPU	Motorola MC68008 (48 pin DIP-version) Intel 8049H111 microcontroller @11MHz the MC68008 was probably the most 'exotic' of the MC680x0-series; externally, it has 20 bit address- and 8 bit data-bus, while internally processing at 32 bit (like all MC680x0). Due to its address-bus, the maximum of directly addressable RAM is 1 MByte the MC68008 is code-compatible with its predecessor MC68000, and was intended as an alternative for cheap 8 bit board-designs there was also a 52 pin PLCC version of the MC68008, with 22 bit address-bus (i.e. 4 MByte addressing range)
Speed	7.5 MHz
RAM	ZX8301 (memory address decoding) 128 KBytes (16 pcs. 64Kx1) this particular machine has been upgraded to 512 KBytes: 16 pcs. TMS4256-12NL (256Kx1) in order to expand the machine's RAM without occupying the internal expansion port, the soldered 64Kx1 RAMs have been replaced by socketed 256Kx1 RAMs. For proper address selection, an additional PAL14L4 has been soldered pickaback onto IC21, and wired to some of the ZX8301's and IC20's pins expandable to 4 MBytes via 3rd party expansions 32 KB of the internal RAM (no matter the amount) are used as video-RAM by the ZX8301, which is responsible for video refresh. Since CPU and ZX8301 access the internal RAM simultaneously, the CPU is occasionally being halted (since video refresh has higher priority). That's also the reason why onboard RAM expansions (e.g. replacing the onboard 64Kx1 chips) do not speed up RAM access times, while RAM connected to the expansion port can increase performance by up to 50%
ROM/ Native OS	Sinclair QL.JM 0000 v1.03 (256Kx1) Sinclair QL.JM 8000 v1.03 (128Kx1) ROMs contain: Sinclair QDOS ('QL disk operating system') Sinclair SuperBASIC QDOS is window-oriented and capable of preemptive multitasking. It also allows dynamic assignment of system resources (e.g. RAM/ ROM addresses) to programs or devices. SuperBASIC is a BASIC derivate, which allows structured programming. In addition to looping and branching in standard BASIC variants, SuperBASIC also allows the definition of functions and procedures there have been several QL ROM-set revisions: 'FB', 'PM' (1984): early production ROMs with lots of bugs. Required an external cartridge ('dongle') for operation 'AH', 'JM' (1984): dongle not needed anymore, less bugs 'JS', 'JSU' (1985): lots of bugs fixed (but also with some new...). JSU was the 1st version developed for NTSC-machines 'MGx': localized ROM-sets for Germany (MGG), France (MGF), Spain (MGE), Sweden (MGS) and Italy (MGI). Additionally, 3rd party ROMs were available (e.g. with greek localization)
Keyboard/ Layout	65 keys/ US (QWERTY) keyboard scanning done by the 8049 IPC there was also a German localized QL with QWERTZ keyboard according to Sinclair User, issue 39, Sinclair has also produced localized keyboards for other countries (e.g. Greece, France). Localized ROMs and software bundles do also exist
Graphics	ZX8301 (video output & refresh) Motorola MC1377P (RGB-to-NTSC/PAL encoding) Text and graphics: Max.Res.: 512x256 (4 colors) Max. Colors: 8 (at 256x256, from a palette of 255) Text: 85x25, 42x25, 64x25 and 40x25 character modes this is a PAL-version; NTSC-versions (US-QLs with 'JSU' ROMs) do exist
Sound	integrated loudspeaker at fixed volume, controlled by the 8049 IPC controllable duration, pitch/ pitch oscillation and distortion effects
Media	2x built-in Sinclair Microdrives a Sinclair-invention and also called 'stringy floppy' each drive controlled by a Ferranti 2G007A ULA 112.64 KB capacity/ tape (QL-format). Speed was 15 KB/ second you could connect up to 8 drives to the QL the media itself was a tiny (34x42mm) cartridge, with a small tape inside (but 5.6 meters in lenght!) Microdrives were also available for the ZX Spectrum, although exchanging data with QL-drives was impossible 3.5" (720 KBytes, 250Kbit/s) drives via DD50 adaptor harddisks with 7 MByte (Sinclair)/ up to 524 MByte (3rd party) via expansion port SCSI/ AT-bus adaptors
Input/ Output	ZX8302 (controlling all I/O signals) Motorola MC1488 (RS232 quad-line driver) Motorola MC1489 (RS232 quad-line receiver) 2x QLAN (to connect directly to other QLs, 100 KBit/s) 8 pin round DIN video output (with both digital RGB- and composite signals) RF-out (TV) 2x 6 pin RS232C (up to 19.2 KBit/s) 2x 6 pin CTL (for joysticks) 28 pin female edge cartridge connector internal 64 pin expansion-bus (e.g. for DD50, memory expansions, harddisk controllers and CPU boards) 7 pin male edge connector (for additional Microdrives) 3 pin power-connector has a reset switch
Miscellaneous	'QL' means 'Quantum Leap' - and indeed: the QL was one of the first 32-bit computers (only preceeded by the Apple Macintosh, which was released two weaks earlier). It came with impressive technical specifications, and an improved keyboard (in comparison to all other Sinclairs). The QL was Sinclair's first attempt to enter professional markets The rare Motorola MC68008 CPU is quite interesting: the DIP version, used in the QL, has a 20 bit address- and an 8 bit data-bus. This made it easy to integrate into existing 8 bit board-designs. After all, cheap and efficient designs have always been a 'Sinclair philosphy' People often complained about the Microdrives (although they were a cheap and efficient solution): the cartridges were said to frequently lose data... The machine came with a software package, that included word-processor, spreadsheet-, database- and graphic application (see picture below) The Sinclair QL was in many ways revolutionary, indeed, but it failed due to many problems in detail (buggy ROM-revisions, release problems). So when AMSTRAD overtook Sinclair's computer line, the QL was finally retired After the QL was discontinued, several companies released unofficial QL-compatibles and clones (like the Sandy QXT 640 or CST Thor-series). These came with improved specifications (e.g. 68000/ 68020-CPUs, onboard disk controllers or improved graphic capabilities). But AMSTRAD would not allow official QL-successors to be built