Editing Amstrad CPC (section)

===The ''plus range''===
In 1990, confronted with a changing home computer market, Amstrad decided to refresh the CPC model range by introducing a new range variantly labelled ''plus'' or ''PLUS'', ''1990'', or ''CPC+ range''. The main goals were numerous enhancements to the existing CPC hardware platform, to restyle the casework to provide a contemporary appearance, and to add native support of cartridge media. The new model palette includes three variants, the ''464plus'' and ''6128plus'' computers and the ''GX4000'' video game console. The "CPC" abbreviation was dropped from the model names.

The redesign significantly enhanced the CPC hardware, mainly to rectify its previous shortcomings as a gaming platform. The redesigned video hardware allows for 16 [[Sprite (computer graphics)|hardware sprites]]<ref>{{cite web |title=Original Arnold V Specs |url=https://www.cpcwiki.eu/index.php/Original_Arnold_V_Specs |website=CPCWiki |access-date=8 January 2025}}</ref> and soft scrolling, with a colour palette extended from a maximum of 16 colours (plus separately definable border) at one time from a choice of 27, increased to a maximum of 31 (16 for background and 15 for hardware sprites) out of 4096. The enhanced sound hardware offers automatic [[DMA transfer]], allowing more complex sound effects with a significantly reduced processor overhead. Other hardware enhancements include the support of analogue joysticks, 8-bit printers, and [[ROM cartridge]]s up to 4 [[megabit|Mbit]]s.

The new range of models was intended to be completely [[backwards compatible]] with the original CPC models. Its enhanced features are only available after a deliberately obscure unlocking mechanism has been triggered, thus preventing existing CPC software from accidentally invoking them.<ref name="ArnoldVSpec">{{cite web|title=Arnold "V" Specification 1.4|last=Lawson|first=Cliff|publisher=Amstrad|url=http://web.ukonline.co.uk/cliff.lawson/arnold5.htm|archive-url=https://web.archive.org/web/20001118214900/http://web.ukonline.co.uk/cliff.lawson/arnold5.htm|archive-date=18 November 2000 |url-status=dead}}</ref>

Despite the significant hardware enhancements, many viewed it as outdated, being based on an 8-bit CPU, and it failed to attract both customers and software producers who were moving towards systems such as the [[Amiga]] and [[Mega Drive]] which was launched a few short months after the plus range. The plus range was a commercial failure,<ref>[[Retro Gamer]] issue 83, From the Archives: Radical Software</ref> and production was discontinued shortly after its introduction in 1990.

====464 plus, 6128 plus====
[[File:6128plus es.jpg|thumb|A ''6128 plus'' main unit (with Spanish keyboard layout)]]
The ''464 plus'' and ''6128 plus'' models were intended as "more sophisticated and stylish" replacements of the CPC 464 and CPC 6128. Based on the redesigned plus hardware platform, they share the same base characteristics as their predecessors: The 464 plus is equipped with 64&nbsp;KB RAM and a cassette tape drive, the 6128 plus features 128&nbsp;KB RAM and a 3" floppy disk drive. Both models share a common case layout with a keyboard taken over from the CPC 6128 model, and the respective mass storage drive inserted in a case breakout.

In order to simplify the [[Electromagnetic compatibility|EMC]] screening process, the edge connectors of the previous models have been replaced with micro-ribbon connectors as previously used on the German Schneider CPC 6128. As a result, a wide range of extensions for the original CPC range are connector-incompatible with the 464 plus and 6128 plus. In addition, the 6128plus does not have a tape socket for an external tape drive.

The plus range is not equipped with an on-board ROM, and thus the 464 plus and the 6128 plus do not contain a firmware. Instead, Amstrad provided the firmware for both models via the [[read only memory|ROM]] extension facility, contained on the included ''Burnin' Rubber and Locomotive BASIC'' cartridge. This resulted in reduced hardware localization cost (only some select key caps and case labels had to be localized) with the added benefit of a rudimentary [[copy protection]] mechanism (without a firmware present, the machine itself could not copy a game cartridge's content).<ref name="ArnoldVSpec"/> As the enhanced ''V4'' firmware's structural differences causes problems with some CPC software directly calling firmware functions by their memory addresses, Amstrad separately sold a cartridge containing the original CPC 6128's ''V3'' firmware.<ref name="GrimwareCartridges">{{cite web|title=Amstrad System Cartridges|publisher=grimware.org|url=http://www.grimware.org/doku.php/documentations/hardware/amstrad.cartridge.released|archive-url=https://web.archive.org/web/20100201131141/http://www.grimware.org/doku.php/documentations/hardware/amstrad.cartridge.released|url-status=dead|archive-date=1 February 2010|access-date=22 March 2010}}</ref>

Both the 464 plus and the 6128 plus were introduced to the public in September 1990. Initial suggested retail prices were {{GBP|229}}/{{currency|1990|code=FRF}} with a monochrome monitor and {{GBP|329}}/{{currency|2990|code=FRF}} with a colour monitor for the 464 plus, and {{GBP|329}}/{{currency|2990|code=FRF}} with a monochrome monitor and {{GBP|429}}/{{currency|3990|code=FRF}} with a colour monitor for the 6128plus.<ref>Paris in the Spring, ''Amstrad Action'' Issue 60, September 1990, P. 34-36</ref>

====GX4000====
[[File:Amstrad-GX4000-Console-Set.jpg|thumb|The Amstrad GX4000]]{{main|Amstrad GX4000}}

Developed as part of the ''plus range'', the GX4000 was Amstrad's short-lived attempt to enter the video game consoles market.  Sharing the plus range's enhanced hardware characteristics, it represents the bare minimum variant of the range without a keyboard or support for mass storage devices.<ref name="ArnoldVSpec"/> It came bundled with 2 [[paddle controller]]s and the racing game ''Burnin' Rubber''.