Test Program Link: Zx Spectrum
Test Program Link: Zx Spectrum
A simple 48K Spectrum test program typically includes:
High-level steps to build such a program:
Example test routines (described, not code):
(If you want actual assembler source, say so and specify target machine: 48K, 128K, or a particular clone.) zx spectrum test program link
Once you have your ZX Spectrum test program link and have downloaded a .TAP file, you need to load it onto your real hardware. Here is the step-by-step process.
If you have recapped a board or replaced RAM, you don't just want to know if it works; you want to know if it will work in an hour.
Once the program loads (you will see a cyan screen with "ZX Spectrum Diagnostic v2.3"), follow this sequence: A simple 48K Spectrum test program typically includes:
Keyboard Matrix Test
ULA vs. Contended Memory Test
Sound and Beeper Test
Video Output Test (The coloured bars)
One of the most famous uses of the test program link was the "Burn-In" test. The original ZX Spectrum issues—particularly the Issue 1 and Issue 2 boards—were prone to overheating and timing glitches.
A standard test program would write specific patterns to the video RAM (checkerboards, stripes, and attribute flashes). If the machine passed this for 48 hours, it was considered stable. High-level steps to build such a program:
The "link" here was crucial: it was the software ensuring the hardware timing stayed in sync. If the ULA overheated, the timing would drift, and the test program would crash, providing a definitive diagnosis that a simple visual inspection could never achieve.
If you are trying to test a "Link" (a connection to an external drive or SD card):