Chapter 1

ZX Spectrum 16K

Sinclair Research Ltd released the ZX Spectrum home computer in the UK, in April 1982. There were two memory configurations: 16 KB of RAM (£125), and 48 KB (£175).

Sinclair ZX Spectrum 16K / Space Raiders (ROM version) by Psion & Melbourne House

Z and X move left and right. 5 to fire.

Some early Spectrum games were available on ROM cartridge, though very few were released this way, because the cartridges were expensive, and required an additional peripheral, the Interface 2. Space Raiders from 1982, is a fairly blatent rip-off of Space Invaders.

// JSSpeccy configuration
emu = JSSpeccy(
    document.getElementById('jsspeccy'),
    {
        machine: 16,
        roms: { Spectrum48K: './G9R_ROM.bin' },
        uiEnabled: false,
        autoStart: true,
        zoom: 2,
    })

In the configuration above, we’ve selected the 16 KB Spectrum machine (“machine: 16”), and specified the URL path to an uploaded Space Raiders ROM ('./G9R_ROM.bin'). (The ROM is specified with “Spectrum48K:”, because the 16 KB and 48 KB models share essentially the same hardware.)

Please note that since we’ve enabled autostart: true, the game starts when this webpage loads, but there is no audio. This is a limitation of web browsers: Scripts are disallowed from playing audio if they start automatically on page load, to avoid irritating the user.

For more detail see the JSSpeccy manual.