"Amstrad CPC.. the European Classic Home Computer"

The rare CPC664

Manufactured between 1984 and 1990, the Amstrad CPC is a series of Z80-based home computers. The CPC competed with ZX Spectrum and Commodore 64 for a market share in the promising 8-bit home computing market. The 464/6128 CPC sold very well in Europe, especially in France and the United Kingdom.

  • CPC stands for Colour Personal Computer
  • In 1990, Amstrad announced the CPC Plus series, featuring improved graphics and stereo sound, however, it was too little too late

CPC6128 running a word processing software (from my collection)...


  • Zilog Z80 CPU running at 4 MHz
  • AMDOS / CP/M operating system
  • 27 colors palette (up to 16 on-screen)
  • AY-3-8912 sound chip with three mono channels
  • 3-inch built-in floppy disk drive (6128) and built-in cassette player (464)
  • A software library of thousands of titles (mostly video games)


Colors & Graphic Modes

The CPC series offers a nice palette of 27 colors. The later CPC+ series offers 4,096 colors (12-bit).

The CPC series offers a nice palette of 27 colors...CPC Video Modes (27-color palette)

  • 160×200 pixels with 16 colors (Mode 0)
  • 320×200 pixels with 4 colors (Mode 1)
  • 640×200 pixels with 2 colors (Mode 2)


Sound Capabilities

The CPC series features the AY-3-8912 sound chip also found in ZX Spectrum, Atari, MSX, Oric,  etc.:

  • Three (3) mono channels
  • Generating square waves (white noise or both)
  • The later CPC+ series features 3 stereo voices, 8 octaves+1 noise channel


Operating System

 The Amstrad CPC used the CP/M as its operating system:

  • CP/M 2.2, CP/M 3.0, or AMSDOS
  • Locomotive BASIC 1.0/1.1

Locomotive BASIC 1.0/1.1

The ROM-based (built-in) Locomotive Basic was written by Locomotive Software on the Amstrad CPC:

  • Locomotive BASIC 1.0, only with the CPC464
  • Locomotive BASIC 1.1, with all other CPC models
  • Locomotive BASIC-2 became a GEM application on the Amstrad PC1512/1640

Later, new operating systems were released for the Amstrad CPCs:


The FutureOS is a multi-featured operating system for the Amstrad CPC6128, 6128plus, C-One, CPC TREX, and KC Compact. FutureOS has been developed by the team called FutureSoft in Z80 assembler from 1989, and up to today (2022).

» The official website of FutureOS

SymbOS□ SymbOS

The SymbOS by Prodatron is a free multitasking operating system for Z80 8-bit systems (Image at the beginning of this article):

  • Available for Amstrad CPC as well as for the Amstrad PCW (Joyce), Enterprise 64/128, and the MSX2 standard
  • Offers a windows-based GUI
  • Pre-emptive and priority-oriented multitasking
  • Managing up to 1024 kB of RAM for the executed applications
  • Supporting hard disc drives with a capacity of up to 2 TB

» The official website of SymbOS

Software Library

  • A software library of more than 3,800 titles
  • A few thousand games
  • Hundreds of applications (word processors, graphics, sound, business applications)


I/O Ports

These are the basic ports of CPCs. Note, that the CPC 464 model lacks the 2nd disc drive and the cassette ports.

On the back of the CPC 6128:

  • Monitor port
  • Printer port
  • 2nd disc drive (only CPC664, CPC6128, CPC6128+)
  • Expansion  port

On the left of the CPC 6128:

  • 9-pin joystick port (compatible with Amiga and Atari joysticks)
  • Cassette port (only CPC664, CPC6128, CPC6128+)
  • 3.5 headphones jack


Expansions & Upgrades

There are a lot of decent upgrades for the CPC, the most interesting one is the M4 Board, which allows SD cards and WiFi access:

  • M4 Board (SD-Card storage and WIFI access) for CPC
  • Gotek Drive replacing the floppy disk drive (loads games through a simple USB stick)
  • 3.5” external floppy disc drive
  • Dk'tronics 64/256K memory upgrade (compatible with CPCs, but not with CPC+)
  • Dandanator Entertainment System (512 KB instant access ROM game cartridges, providing a «console-like» experience)
  • CPLINK, a co-processor link card for the Amstrad CPC (connecting a RaspberryPi, directly to any Amstrad CPC)
  • Multiface II interface
  • MultiPlay MX4 Expansion (allows adding two controllers on the expansion port)


Related CPC Models

From top to bottom... CPC464, CPC664, CPC6128, and CPC6128+These are the CPC variants:

  • CPC 464

Released in 1984, the CPC 464 sold more than two million units. It was the lower-end CPC computer, offering 64K of RAM and a built-in cassette drive.

  • CPC 664

Released in 1985, the CPC664 offered 64K of RAM and a built-in 3-inch floppy disk drive. It is a rare machine these days.

  • CPC 6128

Released in 1985, a few months after the 664 CPC, the 6128 offered the CP/M+ operating system, 128K of RAM, and an internal 3-inch floppy disk drive. It was a successful model for Amstrad, as it sold more than 1 million units.

  • Schneider CPC

The Schneider computer division distributed the Amstrad CPCs on the German market under their brand name Schneider (464, 664, and 6128 models).

  • The Later CPC+ (464+/6128+)

Released in 1990, the CPC+ home computers were also based on Z80 at 4 MHz, offering a 12bit color palette  (4,096 colors) and stereo sound. The Plus series sold well in France, but not as well in the rest of Europe. The US home computer market was out of the radar of CPC+.

  • The Plus series included the 464+ and 6128+
  • CP/M 3.0 operating system and an improved BASIC command set for disc access
  • 4,096 colors palette (12bit), 16 colors on-screen, and hardware sprites
  • 3 stereo voices, 8 octaves+1 noise channel
  • Cartridge Slot
  • Aux socket  (Lightgun)
  • There was also the Amstrad GX4000 game console with the same chipset


Amstrad Sales Figures

These are some basic sales figures regarding the Amstrad CPCs and other Amstrad models.

Table: Amstrad 8-bit computers

Amstrad Sales Figures


Amstrad CPC Computers

Binaryvalue.com 2022 (c) -Sources: CPCWiki.eu, Wikipedia



□ MODELS » Amstrad CPC » ZX Spectrum » C64/C128