Specification of the Amstrad Computers

Introduction

The Amstrad Colour Personal Computer (Amstrad CPC) was designed by Amstrad Consumer Electronics plc., Brentwood, Essex, UK.

It was produced for direct competition against the existing home computers of that time, the ZX Spectrum by Sinclair Research, and the C64 by Commodore.

There are 5 Amstrad computers made between 1984 and 1992. (CPC464,CPC664,CPC6128,464Plus,6128Plus)

The name of the manufacturer can be different for each country. Typically in Germany the Amstrad was called the Schneider.

Amstrad CPC 464

  • Z80A CPU @ 3.3Mhz
  • 64K RAM
  • Locomotive Basic v1.0 (ROM), Amstrad Firmware v1 (ROM)
  • Palette of 27 colours (3 intensitys of red, green and blue)
  • 3 screen modes
  • mode 0: 160x200 - 16 colours
  • mode 1: 320x200 - 4 colours
  • mode 2: 640x200 - 2 colours
  • General Instruments AY-3-8912 Sound Generator @ 1Mhz
  • 8 octave range
  • 3 tone channels
  • tone and volume control
  • 1 noise channel
  • hardware volume envelopes
  • Cathode Ray Controller HD6845 @ 1Mhz
  • Programmable screen size
  • Programmable screen position
  • Scrolling and paging
  • Variable screen displays
    •
  • "Gate Array" custom chip (c) Amstrad Consumer Electronics Plc.
  • colour selection
  • mode selection
  • rom and ram configuration
  • INTEL 8255 PPI Interface chip
  • interface for keyboard scanning
  • interface for AY-3-8912 PSG
  • interface for reading/writing cassettes
  • Miscelaneous sensing (VSYNC/Expansion devices etc)
  • Tape recorder built into keyboard unit
  • Stereo headphones socket
  • Volume control dial
  • 7-bit printer port
  • Expansion port
  • Uk models have a Edge connector
  • German models have a Amphonel D-type connector
  • 1 Joystick port - supports 2 joysticks using special lead
  • UK machines - Edge connectors

    • Amstrad CPC 664

    Same as a CPC464 except:-
  • Locomotive Basic v1.0 (ROM), Amstrad Firmware v1 (ROM), AMSDOS (ROM)
  • General Instruments uPD-765A Floppy Disk Controller @ 4Mhz
  • Double density recording only
  • Support for 2 drives
  • Support for single and double sided disks
  • Support for 3.5" and 5.25" disks
  • Can be used to read Double Density PC disks
  • 3" disc drive built into keyboard unit (instead of tape recorder)
  • each 3" disc is double sided (disc must be turned over to use other side)
  • disc capacity:
  • AMSDOS 178k per side
  • SYSTEM 169k per side (intended for CPM)
  • C/PM 2.2 O/S supplied
  • 5 Pin Din socket for lead to connect to a external tape recorder

    • Amstrad CPC 6128

    Same as CPC664 except:
  • 128K RAM
  • Locomotive Basic v1.1 (ROM), Amstrad Firmware v2 (ROM), AMSDOS (ROM)
  • C/PM Plus disks provided
  • "side 1" - C/PM System
  • "side 2" - C/PM+ Utilities
  • "side 3" - C/PM+ Utilities + Help
  • "side 3" - C/PM 2.2 System, Bank Manager (use 128k from BASIC), Demo of Roland in Time and a demo to show the CPC's capabilites

    • Amstrad 464 Plus

  • Z80 CPU @ 3.3Mhz
  • 64K RAM
  • Backward compatible with CPC464/664/6128
  • Tape recorder built into keyboard unit
  • Locomotive Basic v1.1 (ROM) Amstrad Firmware v3 (ROM), AMSDOS (ROM)
  • AY-3-8912 PSG
  • ASIC custom chip (designed by Amstrad)
  • Emulates the function of the CRTC and 8255 chips in the CPC system
  • Without "unlocking sequence" acts just like Gate Array in CPC. Therefore CPC software is compatible.
  • Only accessible from cartridge games - or so they claimed
  • Pallette of 4096 colours
  • 32 colours on screen, 16 colours display, 16 colours for sprites
  • Pixel hardware scrolling
  • Stereo DMA controlled PSG (capable of stereo 4-bit 15KHz digitised sound)
  • Hardware sprites (16 colours each, resolution independant, can be magnified)
  • Programmable scanline interrupts
  • Programmable split-screen
  • Cartridge Port (for games cartridges)
  • Analogue Joystick Port
  • Light Gun port
  • 8-bit Printer port
  • 2 Joystick ports
  • Monitor Port
  • Headphones socket
  • Expansion connector
  • Connectors use Amphonel D-Type connectors

    • Amstrad 6128 Plus

    Same as 464 Plus except:
  • 128K RAM
  • 3" disc drive built into keyboard unit
  • Locomotive Basic v1.1 (ROM), Amstrad Firmware v3 (ROM), AMSDOS (ROM)
  • Second drive port
  • Doesnt have a built in tape recorder

    • GX4000 - "Games console"

    It's a 464Plus without the keyboard and tape recorder. The GX4000 has:
  • 2 joystick ports
  • Analogue Joystick port
  • Monitor port
  • TV Modulator built in

    • KC Compact

    This was a computer produced in Eastern Europe which was a copy of the CPC. It didnt contain a Gate Array, and this was emulated using some logic chips instead. Some of the port addressess were different, apart from this, not much is known about it's hardware.