to verify the health of both the lower 16K and upper 32K RAM chips. Floatspy & Interrupt Tests : If you're into low-level reverse engineering, the ZX Spectrum Reverse Engineering Blog
You're referring to the ZX Spectrum, a classic British home computer from the 1980s! zx spectrum test program link
A dedicated test program bypasses the human guesswork. It runs systematic checks on: to verify the health of both the lower
is the "Retroleum ZX Spectrum Diagnostic Kit" (a downloadable ROM image and a simple PCB adapter). It has become the gold standard for repair cafes and retro enthusiasts. zx spectrum test program link