On Wed, May 17, 2023 at 5:29 AM Fred Cisin via cctalk <cctalk@classiccmp.org> wrote: > > >> Similarly, he could buy a cheap external USB 3.5" drive. Write content to > >> that drive on the modern machine, and read those floppies on the older > >> machines. The readily avaailable one have firmware that only supports > >> 720K, 1.4M, and [sometimes] NEC-style "mode 3". > > On Wed, 17 May 2023, Tony Duell wrote: > > I have one but AFAIK it only supports 1.4M. A format that few of my > > other machines support. > > Have they stopped making ones that include 720K?
I've never found one that claims to support 720K. OK, OK... When I have a little (?) spare time I'll pull my USB floppy drive to bits and try to work out just what the hardware consists of. > That's something that almost all of your MFM machines could be coerced > into handling. > > >> I get the implication that he is considering USB flux-transition devices > >> that could be coerced into acting as a general purpose floppy controller. > > I am not adequately familiar with them. Nor am I,which is why I am asking about them. I've heard they are a possible solution to my problems. I would like to know more, which ones exist, which are recomended (the Greaseweazel, the only one that has been seriously suggested to me, is at least open source and has schematics available), what they will do, etc And to jump to a later point you make, I want to know just what software tools exist to deal with the flux-transition file (if that's the term). For example for an FM or MFM disk image, are there tools to convert between a .IMD file and said flux transition file, between a .TD0 file and said flux transition file, etc. And what software tools exist to work on disk images. If I have a .IMD file of a CP/M disk, say, can I add a file to it, for example? -tony