#ZXSpectrum #RetroComputing #Z80 #Diagnostics #Homebrew
ld hl, 32768 ; start of 32K RAM area (for 48K) ld de, 32769 ld bc, 32768-1 ld (hl), $FF ldir ; fill with $FF ; ... then verify and repeat with $00, $AA, $55 zx spectrum test program
Just finished a little weekend project – a bare-bones ZX Spectrum diagnostic/test program written in Z80 assembly. Thought I’d share it for anyone restoring old rubber-keyed Speccys or building a clone (like a Harlequin or ZX-UNO). ZX TEST v1
ZX TEST v1.0 ROM CHK: PASS RAM 48K: PASS KB TEST: Press any key... I’ve put the .tap file and source on GitHub → [link] 32769 ld bc
Should I add a ULA snow test or an AY-3-8910 sound check next? Anyone else have a favourite minimal test routine?