Quick status update before I go to bed... The analyser is now reading discs. All the buffer data seems valid, and the nifty "so simple I can't believe I didn't think of it first" counter-rollover algorithm proposed by Peter Coghlan seems to work really nicely too. I've dumped track zero from a DOS 1.4MB floppy and (after a quick bit of histogram analysis) it looks like valid MFM data. I'm seeing a big spike at ~2us, a second, smaller, spike at ~3us, and a third, even smaller spike at ~4us. The last spike is only just noticeable on a linear graph scale -- probably due to the large number of 2us "hits" (39,000 in a 90,000 sample acquisition). On a log scale it's a lot more visible. I haven't tried decoding the data yet, but that's next on the list. Writing isn't implemented yet (I need to do a partial-rewrite and redesign of the disc writer state machine) but I'm quite happy with how this has turned out thus far. I'd post screenshots, but console apps don't tend to make very interesting screenshots... (I'd also cross-post this to VCforum, but I'm too tired to remember my password) Cheers, -- Phil. philpem at philpem.me.uk http://www.philpem.me.uk/