Folks, I do have a version of software that supports READING Intel m2fm on a cat weasel, and will post a link in the coming days - just got back from a road trip.
Sent from my iPad > On Aug 6, 2016, at 18:12, Eric Smith <space...@gmail.com> wrote: > > Because the cwtool support for Intel M2FM floppy disk flux images > isn't publicly available, I've written a crude Python 3 program for > converting such images (in DFI format) to ImageDisk images, and put it > on github: > > https://github.com/brouhaha/dfitoimd > > My ADPLL data separator has parameters to control the proportions of > frequency adjustment and instantaneous phase adjustment that are done > at each flux transition. I've experimented with the parameters quite a > bit, but it's still not good enough to reliably recover all sectors > from the disk images that started this thread. The default parameters > are currently 0.5% frequency adjustment and 10% instantaneous phase > adjustment. I was actually fairly surprised that I didn't get better > results with more frequency adjustment and less instantaneous phase > adjustment. It's entirely possible that my algorithm isn't very good. > > The code can handle normal IBM 3740 single-density FM format as well, > though there are other published programs that already do that. > There's a start at code for IBM System/34 double-density MFM format > also, but it hasn't been tested at all as I don't happen to have any > suitable DFI images. > > The dfitoimd program is quite slow; on a typical Intel M2FM image with > two revolutions per track and 25 MHz sampling, it takes 64 seconds on > a 4.0 GHz AMD CPU. I'm pretty sure that rewriting it in C/C++/C# or > the like would make it much faster, but I specifically chose Python as > I find it easier to experiment with the algorithms.
