Amstrad CPC 6128

Amstrad shipped the CPC 6128 in August 1985 as a disk-equipped 128K home computer with CP/M 3.1, targeting both office tasks and home use across Europe and North America.

The CPC 6128 arrived not as a clean-sheet design but as the second successor in Amstrad’s CPC line, following the CPC 464 and the short-lived CPC 664¹. The 664 featured an integrated 3-inch floppy disk drive, while the 6128 committed fully to disk: a built-in 3-inch floppy drive shipped standard⁶¹⁴¹⁵. This was no minor upgrade. The drive provided access to nearly 1,000 professional CP/M applications, including dBaseII and Multiplan, which ran without adaptation¹⁰¹⁵. The machine shipped with CP/M Plus (CP/M 3.1), chosen specifically because it could manage the 6128’s two 64K RAM banks, unlike CP/M 2.2, which was limited to a single bank¹¹⁰.

Despite the Z80A microprocessor’s 64K addressing limit, the system delivered 128K of usable RAM by bank-switching between two 64K segments¹. ROM held 48K of resident BASIC and operating system firmware¹⁵. The display controller was a 6845, paired with either a green monochrome monitor (GT-65) or a full-colour CTM-644 unit¹⁵. Sound came from the AY-3-8912, a three-voice, eight-octave generator¹⁵. In France, the keyboard followed AZERTY layout with a separate numeric keypad and cursor block¹⁵.

Amstrad initially released the 6128 exclusively in the US in August 1985, priced at $699 or $799 depending on monitor choice⁶. In the UK, it retailed at £299 with a monochrome screen or £399 with colour⁶, though one alternate listing priced the monochrome version with disc drive and printer at £299, suggesting bundle variability⁴. German buyers paid 1,598 Deutsche Mark for the 128K system, a figure hailed at the time as a milestone given the spec¹⁰. In France, the base system cost 2,790 or 3,690 francs depending on monitor, while a full "pack familial" with printer and station micro reached 4,395 francs³.

Design & Compatibility

The machine emphasized plug-and-play readiness: "With a single cable to plug into the mains, the 6128 system is ready to operate"¹¹¹². It was sold in Germany under the Schneider brand, continuing a distribution partnership¹. Backward compatibility was a selling point: every CPC 664 program ran without restriction on the 6128¹⁰. But forward compatibility faltered. Some later 6128 units shipped with altered connectors, breaking compatibility with existing expansions⁸. This provoked criticism: owners of CPC 464s considering an upgrade were warned to "think twice" if they already owned peripherals⁸.

Supply issues plagued the early rollout. Shop availability, especially of colour models, was described as "more than problematic"⁸. The CPC 664 was discontinued around the same time, a controversial move given its transitional role toward the 6128⁶.

Legacy & Successors

At launch, the 6128 was projected to become the strongest model in the CPC series due to its minimal price premium over the 664¹⁰. It bridged markets: marketed as the first micro capable of serving needs "from sixth grade to the office or the shop"¹⁵. CP/M Plus support extended its utility, and the CP/M Plus Handbook published by Digital Research in 1987 covered both the CPC 6128 and the PCW 8256, signaling its role in Amstrad’s broader business ecosystem⁷.

The line evolved again in 1990 with the 6128 Plus, which dropped the "CPC" prefix and added a cartridge slot, shifting focus toward gaming⁶. That model sold for £329 (mono) or £429 (colour)⁶. The CPC range, including clones, was discontinued later that year⁶.

Specifications

References

1. Der SCHNEIDER CPC6128(Jurgen HUCKSTADT)(acme)
2. 24 Schneider PC International 1987-02 (1987)
3. AMSTRAD CENT POUR CENT 12 1989-02(acme) (1989)
4. AcornUser047-Jun86
5. CPC 32(acme)
6. Computers that made Britain v1
7. 8BIT MART 04[OCR]
8. CPC 24(acme)
9. AMSTRAD CENT POUR CENT 07(acme)
10. 10 Schneider CPC International 1985-12 (1985)
11. Amstrad Semanal 013
12. Amstrad Semanal 013
13. AMSTRAD CENT POUR CENT 33 1991-01(acme) (1991)
14. Computer And Video Games Issue 049 Nov 85
15. AMSTRAD CENT POUR CENT 23 1990-02(acme) (1990)
16. Γλώσσα μηχανής για αρχάριους στον Amstrad (Steve Kramer)