Qaop/Java
Qaop/JS

ZX Spectrum ULA timing tests

btime · ULA border timing (btime.tap)
stime · ULA screen timing (stime.tap)
ulatest3 · floating bus and contention (ulatest3.tap)
minfo · frame length etc. (minfo.tap)

sources (needs mktap, mktap.exe)

fusetest, contention, iocontention by Philip Kendall (src)
z80tests by Mark Woodmass
Timing Tests by Richard Butler
zexfix · zexall by Frank Cringle + J.G.Harston − errors (zexfix.tap)
zexbit · zexfix narrowed to bit instruction (zexbit.tap)

« Qaop/Java | Run these tests in Qaop emulator in JavaScript

zx2gif-0.12.tar.gz · SCR to GIF, extracts screens from tapes and snapshots. (Windows binary: zx2gif.exe)
z2gz.cgi-3.tar.gz · ZIP to Gzip extractor CGI. (eg. to serve .tap.gz files directly from zips; no longer needed by Qaop)

See also:

JS local file access. Read file with JavaScript, handle drag&drop, clipboard etc.
How to enable CORS. Make resources available to others' scripts.
Harlequin project (ZX Spectrum clone) by Chris Smith.
Java Z80 comparison utils by Mikko Nummelin.