USB Universal Floppy Disk controller

On Fri, 2005-03-11 at 07:51 +0000, Philip Pemberton wrote: Well if worst-case is 1mbps data rate at 300rpm and 8x oversample, isn't that (8 * 10240 * 1024) / 5 = 1677722 bits of memory maximum needed? (div by 5 because 300rpm gives you a whole track in 1/5 of a second) So 256KBytes of RAM should always be enough to buffer a whole track, regardless of what physical drive or media you use. Presumably there's no need to have any kind of microprocessor control; it can all be done with a free-running clock to read from the drive or write to it, and a few control lines to for read/write, start, stop etc. Can static RAM can't cope with these kinds of speeds? Presumably cache chips pulled from old PC motherboards would cope happily, even if old 80's parts wouldn't. It's probably still beyond my abilities to design something that'd work :-) But on the surface it doesn't sound *that* complicated for someone who's used to designing digital circuits. Oh boy. I rsync data from my desktop to an external hard disk periodically (usually once or twice a week). Hadn't done it for a few weeks, kicked off a run the other day, and the wholse SCSI subsystem fell over. Panic for a moment, thinking my desktop drive had died. Turns out I'd set the SCSI data rate to the external disk higher than normal when I was playing around with something else, and forgotten to set it back again - so it was just a SCSI bus transfer problem, not a hardware issue. Phew. cheers J.