''Taken Modified from [http://en.wikipedia.org/w/index.php?title=ZX_Spectrum Wikipedia']'
The '''ZX Spectrum''' (the "Z" is pronounced "Zed" in its original [[British English]] branding) is an 8-bit personal home computer released in the United Kingdom in 1982 by Sinclair Research Ltd. Referred to during development as the ''ZX81 Colour'' and ''ZX82'', the machine was launched as the ''ZX Spectrum'' by Sinclair to highlight the machine's colour display, compared with the black-and-white of its predecessor, the [[ZX80/81|Sinclair ZX81]]. The Spectrum was released in eight different models, ranging from the entry level model with 16KB RAM released in 1982 to the ZX Spectrum +3 with 128 KB RAM and built in floppy disk drive in 1987; together they sold in excess of 5 million units worldwide.
The Spectrum was among the first mainstream audience home computers in the UK, similar in significance to the Commodore 64 in the USA. The introduction of the ZX Spectrum led to a boom in companies producing software and hardware for the machine, some credit it as the machine which launched the UK IT industry. Licensing deals and clones followed, and earned Clive Sinclair a knighthood for "services to British industry".
The [[c64|Commodore 64]], [[BBC Microcomputer Micro]] and later the [[CPC|Amstrad CPC]] range were major rivals to the Spectrum in the UK market during the early 1980s. The ZX Spectrum has enjoyed a resurgence in popularity thanks to the accessibility of ZX Spectrum emulators, allowing 1980s video game enthusiasts to enjoy classic titles without the long loading times associated with data cassettes. Over 20,000 titles have been released since the Spectrum's launch and new titles continue to be released, with over 90 new ones in 2010. <br>
==Hardware==
Sound output is through a beeper on the machine itself. This is capable of producing one channel with 10 octaves. The machine also includes an expansion bus edge connector and audio in/out ports for the connection of a cassette recorder for loading and saving programs and data.
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==Firmware==
The BASIC was developed from that used on the ZX81 and a ZX81 BASIC program can be typed into a Spectrum largely unmodified, but Spectrum BASIC included many extra features making it easier to use. The ZX Spectrum character set was expanded from that of the ZX81, which did not feature lower-case letters. Spectrum BASIC included extra keywords for the more advanced display and sound, and also supported multi-statement lines. The cassette interface was also much more advanced, saving and loading around four times faster than the ZX81, and much more reliably. As well as being able to save programs, the Spectrum could in addition save the contents of arrays, the contents of the screen memory, and the contents of any defined range of memory addresses.
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==Sinclair Research models==
[[File:ZXSpectrum48k.jpg|right|350px|thumb|ZX Spectrum 16K/48K (Dimensions (mm): 233*144*30 (W*H*D) @ ~552 grams)]]
[[File:ZX Spectrum+.jpg|thumb|ZX Spectrum+ (Dimensions (mm): 319?149?38 (W?H?D))]]
[[File:ZX Spectrum128K.jpg|thumb|ZX Spectrum 128]]
===Pre-production designs===
The Spanish version had the "128K" logo in white while the English one had the same logo in red.
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== Timex models ==
[[File:Timex sinclair 2068.jpg|thumb|right|Timex Sinclair 2068]]
[[File:Timex Computer 2048.jpg|thumb|right|Timex Computer 2048]]
=== Timex Sinclair 2068 ===
The TS 2068 was released in November 1983. It was Timex Sinclair's third and last home computer for the United States market.
It is a more sophisticated computer compared to its UK ancestor, the ZX Spectrum. It added a number of new features:
*an AY-3-8912 sound chip, as later used by Sinclair in the ZX Spectrum 128 (but mapped to different I/O ports and thus incompatible)
*twin joystick ports
*a slightly better "chiclet keyboard" with plastic keycaps
*a cartridge port to the right of the keyboard for ROM-based software
*Timex SCLD chip instead of the Spectrum's ULA, offering additional Extended Color, Dual Screen and High Resolution screen modes:
**Text: 32×24 characters (8×8 pixels, rendered in graphics mode)
**Graphics: 256×192 pixels, 15 colours (two simultaneous colours - "attributes" - per 8×8 pixels, causing attribute clash)
**Extended Color: 256×192 pixels, 15 colors with colour resolution of 32×192 (two simultaneous colours - "attributes" - per 8×1 pixels)
**Dual Screen: (two 256×192 pixels screens can be placed in memory)
**High Resolution: 512×192 mode with 2 colours (Four palettes: Black & White, Blue & Yellow, Red & Cyan, Magenta & Green).
*improved TS 2000 BASIC, that extends Sinclair BASIC with new keywords to address new hardware and bank-switched memory, allowing ROM cartridges to be mapped in.
Because Timex added more commands, the ROM could not fit on 16K so an 8K ROM was added. Timex moved some of the original ZX BASIC commands to this new 8K ROM, making programs that used ROM routines unusable.
With this change, only about 7% of ZX Spectrum software worked on TS2068. Using a ZX Spectrum ROM cartridge fixes it, raising compatibility to 97%.
=== Timex Computer 2068 ===
When Timex Computer Corp folded in North America in February 1984, Timex of Portugal made a new version of the SCLD chip to support PAL TVs. It was marketed as Timex Computer 2068, ditching the Sinclair brand of it.
A variant was sold in Poland after 1986 under the name Unipolbrit Komputer 2086.
=== Timex Computer 2048 ===
Timex of Portugal also produced the Timex Computer 2048, a modified TC2068 to be a Sinclair ZX Spectrum clone, more affordable than the TC2068 and more reliable than the ZX Spectrum since it uses fewer ICs.
The AY-3-8912 sound generator and the cartridge port were removed, the 2 joysticks ports were replaced by 1 Kempson joystick port and the TC2068 ROMs were replaced with a ZX Spectrum ROM. Because the TC2048 uses the same SCLD chip that TC2068 uses, it also has the special display modes of TC2068.
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== Amstrad models ==
In April 1986, Amstrad acquired Sinclair for 5 million pounds. See [https://youtu.be/rGzqvyKYVVI The Amazing TRUE Story Of How Amstrad Bought Sinclair] by [[ChinnyVision]].
At the time of the Amstrad deal, Sinclair was well advanced with development plans for a new Spectrum micro - the £200 SuperSpectrum. The full details can be found here: [https://sinclairuser.com/051/loki.htm Sinclair User article - June 1986]
=== ZX Spectrum +2 ===
[[File:ZX Spectrum Plus2+2.jpegjpg|thumb|ZX Spectrum +2]]The '''ZX Spectrum +2''' was [[Amstrad]]'s first Spectrum, coming shortly after their [[Sinclair Research Ltd#Amstrad acquisition|purchase of the Spectrum range and "Sinclair" brandResearch Ltd]] in 1986. The machine featured an all-new grey case featuring a spring-loaded keyboard, dual joystick ports, and a built-in cassette recorder dubbed the "Datacorder" (like the [[Amstrad CPC 464]]), but was in most respects identical to the ZX Spectrum 128. The main menu screen lacked the Spectrum 128's "Tape Test" option, and the ROM was altered to account for a new 1986 Amstrad copyright message. These changes resulted in minor incompatibility problems with software that accessed ROM routines at certain addresses. Production costs had been reduced and the retail price dropped to £139–£149.
The new keyboard did not include the BASIC keyword markings that were found on earlier Spectrums, except for the keywords ''LOAD'', ''CODE'' and ''RUN'' which were useful for loading software. This was not a major issue however, as the +2 boasted a menu system, almost identical to the ZX Spectrum 128, where one could switch between 48k BASIC programming with the keywords, and 128k BASIC programming in which all words (keywords and otherwise) must be typed out in full (although the keywords are still stored internally as one character each). Despite these changes, the layout remained identical to that of the 128.
The power supply of the ZX Spectrum +2A used the same [[pinout]] as the +3. However, the power supply purchased with the +2A/B had "Sinclair +2" written on the case.
Starting with the +2A, a Gate Array chip produced by Amstrad incorporates the functionalities from the ULA, PCF and HAL chips into a single package. It comes in QFP form instead of the traditional DIP.
=== ZX Spectrum +3 ===
[[File:ZX Spectrum Plus3.jpeg|thumb|ZX Spectrum +3]]
The '''ZX Spectrum +3''' looked similar to the +2 but featured a built-in 3-inch [[floppy disk]] drive (like the Amstrad CPC 6128) instead of the tape drive, and was in a black case. It was launched in 1987, initially retailed for £249 and then later £199 . The ZX Spectrum +3 included CP/M support in ROM and was the only Spectrum capable of running the [[CP/M]] operating system without additional hardware, allowing access to its vast library of available software.
The +3 saw the addition of two more 16 kB ROMs. One was home to the second part of the reorganised 128 ROM and the other hosted the +3's disk operating system. This was a modified version of Amstrad's [[PCWDOS]] (the disk access code used in [[LocoScript]]), called +3DOS. These two new 16 kB ROMs and the original two 16 kB ROMs were now physically implemented together as two 32 kB chips. To be able to run CP/M, which requires RAM at the bottom of the address space, the bank-switching was further improved, allowing the ROM to be paged out for another 16 kB of RAM.
The ''ZX Spectrum +2B'' and ''ZX Spectrum +3B'' were functionally similar in design to the Spectrum +2A and +3. The main electronic differences being simply changes to the generation of the audio output signal to resolve problems with [[Clipping (audio)|clipping]] and the removal of the external tape loading input ("ear" pin).
Unlike the +2A , the Spectrum +2B motherboard (AMSTRAD part number Z70833) does not have provision for floppy disk controller circuitry so cannot be assembled as a +3B. The +3B motherboard is Amstrad part number Z70835. <br>
==Notes==
* From an Amstrad CPC user's point of view, the ZX Spectrum is well known for being the source of [[Speccy Port|Speccy Ports]].
* The Spectrum +2 case design is comparable to the CPC464's case design because of the internal datacorder. The Spectrum +3 design shares some similarities with the CPC6128, the case design is similar with it's internal 3" disc drive, and the disc controller is the same as the CPC6128's. The CPC464 and CPC6128 came before these Spectrum's, so it is clear Amstrad used those as inspirations to update the Spectrum design.
* In France, every machine that didn't provide an RGB output was doomed as TVs were in SECAM, not PAL. Had Sinclair understood the need for an RGB output in France, the ZX Spectrum would have certainly been a success there, just like it did in the UK and Spain. The success of the [[Oric 1/Atmos|Oric]] in France proves it.
=== Links General Sound ===
"General Sound" (GS) is a sound card for ZX-Spectrum 48/128/etc... developed by X-Trade in 1997 as a commercial product. It is a 4 channel, 8-bit sound board with similar sound capabilities as the [[Amiga]] Paula chip. It has its own Z80 CPU onboard running at 12MHz, and 128KB of memory (16KB ROM and 112KB of RAM). The GS was very popular in Eastern Europe. [https://spectrumcomputing.co.uk/entry/1000171/Hardware/General_Sound Source] <br> == Links == * [https://youtu.be/QIxf9bUit_g Over 100 ZX Spectrum 48K games in under 1 hour]* [https://youtu.be/4MjqKswDx8I Over 50 ZX Spectrum 128K games in 30 minutes] [https://youtu.be/PUE4yboY5hk 25 modern games that push the limits]* [https://www.youtube.com/watch?v=yOorvZ1nlzg&list=PLxOanVBhqd3tzVff-Ii1Eo1ykLSdLAnrV ZX Spectrum All Years TOP 10 playlists] [https://youtu.be/jLN4WhGruUY 5 hours with 600+ top quality colourful games] [https://youtu.be/Wd7lHltOGbA 3000 ZX Spectrum HD clips]* [https://www.youtube.com/watch?v=CxPG2GUoUTE&list=PLxOanVBhqd3uSP_gBFdIkEvPxwuQr7DvA ZX Spectrum 48K Beeper chiptunes] [https://www.youtube.com/watch?v=e-3G2Fnh0YQ&list=PLxOanVBhqd3s-6c4Mz7h9NWFgKRvq_ipz ZX Spectrum 128K AY chiptunes]
* [https://youtu.be/MPSSJ_hFYhQ ZX Spectrum Commercials]
* [https://youtu.be/l5N937V8ZOw Sinclair C5 Infomercial] The ideal vehicle for ZX Spectrum lovers
* [https://sinclair.zilog.fr Sinclair's Spirit (FR)] Learn how to code with Z80 Assembler on ZX Spectrum with [[BDCIron]]
* [https://problemkaputt.de/zxdocs.htm Noca$h's ZXdocs] [https://spectrumcomputing.co.uk/entry/2000357/Book/Spectrum_Hardware_Manual Spectrum Hardware Manual] [https://pdfcoffee.com/the-zx-spectrum-ula-how-to-design-a-micro-chris-smith-pdf-free.html The ZX Spectrum ULA ebook]* [https://worldofspectrum.net/documentation/ ZX World of Spectrum documentation]* http[https://scratchpadwww.wikiaspectrumforeveryone.com/wikitechnical/ZX_Spectrum_technical_information* Spectrum for Everyone] [https://sinclair.wiki.zxnet.co.uk Sinclair Wiki] Documentation
* [https://worldofspectrum.net/pub/sinclair/ World of Spectrum file server]
* [https://tzxvault.org/ The TZX Vault]
* [https://www.speccy.org/ Speccy.org] El portal español del Spectrum
* [https://youtu.be/I9dHI6EwWTU Sinclair ZX Spectrum Story - Birth of a Classic] by [[Nostalgia Nerd]]
* [https://youtu.be/fTKckoSj-OE Timex Sinclair 2068 - The American ZX Spectrum] by [[The 8-Bit Guy]]
* [https://youtu.be/36TtdthpKT8 Electronica CIP-03 - Le ZX Spectrum Roumain !] by [[Olipix]]
* [https://www.sinclaircollection.site/ Sinclair Collection Site] [https://en.wikipedia.org/wiki/List_of_ZX_Spectrum_clones List of ZX Spectrum clones]
* [https://www.youtube.com/watch?v=JfZ77Ltkols&list=PLIX9fyYxV0k_VOgMOIxseJH1c91KKcxKB ZX Spectrum vs Amstrad CPC] [https://www.youtube.com/watch?v=Wce82Q54dpA&list=PLIX9fyYxV0k_CanGbwkXdtlhmdtO62ZRW ZX Spectrum vs C64]
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[[Category: Non CPC Computers]] [[Category:Amstrad Products|*]] [[Category:CPC History]]
[[Category:CP/M]]