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''The following text was copied in part from the [http://en.wikipedia.org/wiki/Amstrad_CPC english English Wikipedia article].''

All CPC models were based on a [[Zilog ]] [[Z80 ]] processor clocked at 4 MHz. Because a common pool of RAM is shared with the video circuits, the Z80 may only make a memory accesses access once every four cycles - , which has the effect of rounding all instruction cycle lengths up to the next multiple of four.For details, see [https://web.archive.org/web/20170324233713/http://www.grimware.org/doku.php/documentations/devices/z80 a nearly complete list of instructions with timings (number of cycles) for each.] The system came with 64 KB or 128 KB of RAM depending on the model (capable of being expanded to more). The machines also featured a standard 9-pin Atari-style joystick socket which was able to take two joysticks via a splitter. The machines' dimensions are:*'''CPC464''' : 17 x 57.5 x 7.5*'''CPC6128''' : 17.5 x 51.1 x 5

Underlying the CPCs CPC's video output was the [[CRTC|Motorola 6845 ]] address generator. This chip was connected to a pixel generator that supported 4 bpp, 2 bpp and 1 bpp output (bits per pixel). The address generator was clocked at a constant rate so the 4 bpp display generated half as many pixels as the 2 bpp and a quarter as many as the 1 bpp.

The standard [[video modes ]] were:*'''Mode 0''': '''160×200''' pixels with 16 colors colours (4 bpp)*'''Mode 1''': '''320×200''' pixels with 4 colors colours (2 bpp)*'''Mode 2''': '''640×200''' pixels with 2 colors colours (1 bpp)*'''Mode 3''': '''160×200''' pixels with 4 colours (2 bpp) (this is not an official mode, but rather a side-effect of the hardware)

A colour palette of 27 colors colours was supported, derived from RGB colour space with each component assigned as either off, half on or on. The later '''Plus''' models extended this to 4096 colours and added support for hardware sprites.

This hardware compares well with the other 8-bit computers. In particular the CPC lacks the colour clash of the ZX Spectrum , and clever programming of the 6845 could produce overscan, different resolutions (although with the same pixel density) and smooth pixel scrolling.

The five-pin DIN connector is capable of driving a SCART television with a correctly wired SCART lead.

Output was provided in mono by a small (4 cm) built-in loudspeaker with volume control, driven by an unusually powerful amplifier. Stereo output was provided through a 3.5mm headphones headphone jack, not present on some early CPC464 models. In those models, what looked like a standard 3.5" headphone jack was actually used for connecting an external tape recorder, although later models used a five-pin DIN connector for the same purpose.

The disk drive interface with the drives was a NEC 765 FDC, used for the same purpose in the IBM PC/XT, PC/AT and PS/2 machines. Many of its features were unused in order to cut costs, namely DMA transfers and support for single density disks; they . Disks were formatted as double density using Modified frequency modulationFrequency Modulation.

Disks were shipped in a paper sleeve or a hard plastic case resembling a compact disc "jewel" case. The casing is thicker and more rigid than that of 3.5" diskettes and the sliding metal cover to protect the media surface is internal to the casing and latched, unlike the simple external sliding cover of Sony's version (some reviews at the time reported driving over them with no problems). Because of this they were significantly more expensive than both the 5.25" and 3.5" alternatives. This, combined with their low nominal capacities and their essentially proprietary nature, lead to the format being discontinued when the CPC itself was discontinued.

Apart from Amstrad's other 3" machines (, the PCW and the ZX Spectrum +3(produced by Amstrad after their acquisition of the Spectrum from Sinclair), the only other computer systems to use them were the Sega SF-7000 and mostly obscure and exotic CP/M systems such as the Tatung Einstein and Osborne machines. It should be noted that some of these machines used drives with different pinouts and care should be taken when replacing drives.

A more popular alternative was to attach an adapted IBM-PC 3½" drive for operation in either single-sided 180 KB or double-sided 360 KB mode, although with the later availability of the PARADOS Disc Operating System, 720k per disc became available.(It was possible to patch CP/M Plus so that it recognised 80 track double sided disk formats, too.)

The CPC has been termed an "improved Z80 implementation of the (earlier) BBC Micro" due to similarities in firmware and hardware. Both use used the Motorola 6845 video address generator and the two have very similar sound output chips - the General Instrument AY-3-8912 in the CPC provides provided three tone channels each optionally with added noise and the Texas Instruments SN76489 in the BBC offers offered three tone channels and one exclusive noise channel.

The BBC Micro uses used an Intel 8271 floppy disc controller. The CPC uses used the Intel 8272, which is similar to the 8271 but contains the addition of a double density (MFM) mode.

The "two cursor" BASIC editing system seen on the Amstrad CPC (whereby holding Shift and using the cursor keys moves a shadow text cursor allowing text to be copied from another area of the screen to the normal cursor) is was a lift from BBC BASIC, albeit substantially improved by allowing free movement of the normal cursor.

Both systems provide provided similar systems of full hardware abstraction through Operating System calls. This saves programs which don't require time critical hardware access from having to touch the underlying machine and provides a level of machine portability for those programs.

It exists a to As the graphic and sound capabilities adapted CPC had its own dialect of [[BASIC]], namely [[Locomotive BASIC]], so the BBC Micro has its own version named [[BBC BASIC]]. BBC BASIC evolved with subsequent models of BBC computers and with Acorn's next system, the Archimedes. Both had their own sets of advantages: Locomotive BASIC was faster in many contexts, had native support for text windows, had more comprehensive commands for manipulating sound, ''etc.''; BBC BASIC had support for procedures (rather than just arithmetic functions), an inline assembler, and others. Of note is the fact that among the numerous [http://www.bbcbasic.co.uk/bbcbasic.html ports of BBC Basic] produced by the company [http://www.rtrussell.co.uk/ R.T. Russell] is a version especially adapted for the Amstrad CPC, including support for its specific graphics and sound capabilities; there is also a generic version for [[CP/M]].

Although it was possible to obtain compilers for Locomotive BASIC, BCPL, C, Forth, and Turbo Pascal the majority of the CPC's software was written in native Z80a Z80 assembly language.

An interpreter for the educational language LOGO was also supplied with the 664 and 6128 (and availablefor the 464 with purchase of an external disc drive).

* [[472]] ==Included What was in deliverythe box?==

 * The computer itself, incl. including built-in [[Datacorder]]* [[Demonstration tape or disc|Demonstration tape ]] in local language (UK, Germany, France, Spain)* [[User Manual]]

<gallery>Image:CPC464_pcb_r1.jpg|CPC464 PCB revision 0 (original)Image:CPC464_pcb_r3.jpg|CPC464 PCB revision 3 (costdown)Image:CPC464_new_amstrad_logo.jpg|CPC464 (new Amstrad logo - photo from costdown model)</gallery> === DDI-1 CPC472 ===* Controller DDI-1* 3" disk drive FD-1* [[System Disk]]: CP/M 2The CPC 472 was a spanish version of the CPC 464 with additional (nonfunctional) 8 KB RAM.2 disk The reason for this was that Amstrad wanted to circumvent a Spanish law that levied an extra tax for machines with demo* Manual64KB or less of memory; thus, they upped the spec to 72KB by including an additional 8KB though this extra memory was not functional.

 * The computer itself, incl. including built-in 3" disk drive

* [[User Manual]]

 * The computer itself, incl. including built-in 3" disk drive

* [[User Manual]]

=== CPC464plus ===* The computer itself, incl. built-in Datacorder* System Cartridge with AMSDOS(!), Locomotive BASIC 1.1 and the game Burnin' Rubber* 1 Paddle[[Keyboard Versions]]* CPC464plus/CPC6128plus manual[[Mainboard Versions]]* Game manual[[CPC6128_Keyboard_Disassembled]]* Monitor, either amber or colour[[CPC464 & CPC664_logos | CPC Case logos]]

==Clones= CPC6128plus ===* The computer itself, incl. built-in 3" disk drive* System Cartridge with AMSDOS, Locomotive BASIC 1.1 and the game Burnin' Rubber* [[System Disk]] with CP/M Plus and utilities, identical disk for all countries* 1 Paddle* CPC464plus/CPC6128plus manual* Game manual* Monitor, either amber or colour