Amstrad CPC
Alan Sugar stood before the 1984 British electronics market with a clear directive. He wanted to build an all-in-one home computer that did not look like a toy. The Amstrad CPC launched in June of that year, bundled with its own monitor and keyboard in a single unit. This design choice separated it from competitors like the ZX Spectrum or Commodore 64, which relied on separate television sets and tape recorders. Sugar described his vision as creating a machine similar to what one would see at an airport check-in desk for holidays. He explicitly rejected the "pregnant calculator" aesthetic common among cheaper systems of the era. The initial price point for the CPC 464 was set at £249.00 with a green screen monitor. This strategy targeted families who needed a complete system without buying extra peripherals. The result was immediate commercial success, with sales reaching over two million units by the end of the decade.
The CPC 464 featured 64 kilobytes of RAM and an internal cassette deck when introduced in June 1984. A second model arrived on the 25th of April 1985, known as the CPC 664. This version replaced the cassette drive with a 3-inch floppy disk drive and increased the memory capacity options. The CPC 664 cost £339.00 with a green screen and £449.00 with a colour monitor. Amstrad redesigned the keyboard area to be more ergonomic, tilting it forward and using grey keys instead of the multicoloured buttons found on earlier models. Production of this specific unit lasted only about six months before being discontinued in late 1985. The final major iteration, the CPC 6128, launched on the 13th of June 1985. It offered 128 kilobytes of RAM and retained the floppy drive. This model became the first Amstrad product sold in the United States through Indescomp Inc. of Chicago. Its initial price was US$699.00 with a green screen or US$799.00 with a colour monitor.
Amstrad introduced the plus range in September 1990 to refresh the aging hardware platform. The new lineup included the 464plus and 6128plus computers alongside the GX4000 video game console. These machines featured enhanced video capabilities allowing for 16 hardware sprites and soft scrolling. The sound hardware gained automatic DMA transfer to reduce processor overhead during complex audio sequences. Despite these technical improvements, the market had moved toward systems like the Amiga and Mega Drive. Consumers viewed the 8-bit CPU as outdated compared to newer competitors. The commercial failure was absolute, leading to production discontinuation shortly after launch. The GX4000 console attempt also failed to gain traction because it lacked a keyboard and mass storage support. The redesign significantly enhanced the CPC hardware but could not overcome the shifting technological landscape of the early 1990s.
Spain briefly imposed an import tax of 15,000 pesetas on computers containing 64 kilobytes or less of RAM in August 1985. To circumvent this law, Indescomp created the CPC 472, a modified version of the CPC 464. This unit included a small daughter board with an extra 8 kilobyte memory chip to increase total specs to 72 kilobytes. The machine also featured a Spanish keyboard layout with the distinctive "ñ" key. Production stopped once Spain joined the European Communities later that year. In East Germany, the Kleincomputer KC compact appeared in October 1989 as a clone built by VEB Mikroelektronik. It offered 64 kilobytes of memory and ran customized firmware compatible with Amstrad software. Only a very small number of these systems were sold before German reunification ended production. Russia saw the release of the Aleste 520EX in 1993 by Patisonic, which was highly compatible with the CPC 6128 and could switch into MSX mode.
Locomotive BASIC served as the primary operating system for the entire series, providing easy access to video and audio resources. Users could utilize commands like AFTER and EVERY for timed event handling without complex POKE instructions. Digital Research's CP/M operating system came bundled with disk-based models including the 664 and 6128. These machines shipped with CP/M 2.2 or CP/M 3.1 depending on their RAM capacity. Third-party software libraries included word processors such as Protext and programming utilities like MAXAM. The ROM extension facility allowed users to load extra software from external boxes containing 16 kilobyte blocks. Popular applications were marketed on ROM to ensure faster loading times than disc or tape alternatives. Despite the availability of compilers for C and Pascal, most software was written in native Z80 assembly language.
The core processor for every model was the Zilog Z80A clocked at 4 megahertz. CPU memory access had to occur on microsecond boundaries to prevent video corruption known as "snowing." This constraint padded every machine cycle to four clock cycles, resulting in an effective clock rate of approximately 3.3 megahertz. Video output utilized a Motorola 6845 CRTC paired with a custom gate array. Three display resolutions were available: 160 by 200 pixels with 16 colours, 320 by 200 pixels with 4 colours, and 640 by 200 pixels with 2 colours. Audio generation relied on the General Instrument AY-3-8912 sound chip providing three channels. Output came through a mono speaker measuring 4 centimeters or via a stereo headphone jack. The system lacked RF television or composite video outputs, shipping instead with a 6-pin RGB DIN connector.
Common questions
When did the Amstrad CPC launch in 1984?
The Amstrad CPC launched in June of 1984. This release date marked the introduction of an all-in-one home computer bundled with its own monitor and keyboard.
What was the initial price of the Amstrad CPC 464 model?
The initial price point for the Amstrad CPC 464 was set at £249.00 with a green screen monitor. This strategy targeted families who needed a complete system without buying extra peripherals.
Which models were included in the Amstrad plus range released in September 1990?
Amstrad introduced the 464plus and 6128plus computers alongside the GX4000 video game console in the plus range. These machines featured enhanced video capabilities allowing for 16 hardware sprites and soft scrolling.
How many kilobytes of RAM did the Amstrad CPC 472 contain to bypass Spanish import taxes?
The modified version known as the Amstrad CPC 472 contained 72 kilobytes of memory total. It achieved this by including a small daughter board with an extra 8 kilobyte memory chip on top of the base 64 kilobytes.
What operating systems came bundled with disk-based Amstrad CPC models like the 664 and 6128?
Digital Research's CP/M operating system came bundled with disk-based models including the 664 and 6128. These machines shipped with CP/M 2.2 or CP/M 3.1 depending on their RAM capacity.
What processor clocked at 4 megahertz powered every model in the Amstrad CPC series?
The core processor for every model was the Zilog Z80A clocked at 4 megahertz. CPU memory access had to occur on microsecond boundaries to prevent video corruption known as snowing.