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Spectrum 128K +3
Technical Specification
Amstrad promotional brochure, 1987

Memory

  • RAM: 128 Kbytes on 8x16K pages
  • ROM: 64 Kbytes as 4x16K pages

CPU

  • Z80A running at 3.54690 MHz

Screen

  • 256x192 Pixel resolution
  • 24x32 Colour resolution
  • 8 colours foreground, 8 colours background, plus intensity and flash settings
  • Start of buffer switchable
  • Independently controllable border

Sound

  • Three voices tone and/or noise with 16 envelope settings
  • One voice CPU generated
  • Output via TV, Audio or Monitor

Keyboard

  • 58 key full travel QWERTY keyboard

Storage

  • Integral 3 inch disk drive, single-sided reversible media
  • 40 track, 9 sector, 512 bytes/sector
  • CP/M compatible structure
  • Optional second disk drive
  • Volatile RAM drive
  • Interface for external cassette recorder

Firmware

  • 48K Spectrum BASIC (compatibility mode)
  • 128K Spectrum ZX +3 BASIC integrated with +3 DOS
  • Storage selection by reassignable default with optional override

Interfaces

  • UHF PAL TV port
  • Serial interface (RS232) port
  • Parallel Printer port (8 bit)
  • Auxiliary interface port
  • RGB Monitor (and PERITEL TV) port
  • MIDI output port
  • Two Joystick ports
  • Audio Out/Cassette port
  • Second Disk Drive port
  • Expansion I/O port (full Z80 bus)

Made in Taiwan