Chapter 5

ULAplus

Even into the 2000s, 2010s and 2020s, the Spectrum continues to be popular with enthusiasts and retro-games geeks. In 1999, a standard called ULAplus extended the machine’s colour palette from 15 colours to (up to) 256 colours.

ULAplus is implemented in many emulators (including this one), and in recent hardware revivals, such as The Spectrum (2024). Video adapters for the original 1982 Spectrum, such as the ZX-HD and ZX-VGA, incorporate it too.

Sinclair ZX Spectrum 128K / ULAplus demo

// JSSpeccy configuration
emu = JSSpeccy(
    document.getElementById('jsspeccy'),
    {
        machine: 128,
        openUrl: './ulaplus-colours.szx',
        uiEnabled: false,
        autoStart: true,
        zoom: 2,
    })

The configuration above, selects 128 KB Spectrum model (“machine: 128”), and pre-loads a .SZX-format memory snapshot of one of the standard ULAplus demos.