On 5/16/23 16:04, Fred Cisin via cctalk wrote: > > > For Jim Brain's Coco disk, my inclination would be to image it on an ISA > machine using the WD controller. but, an argument was made that a flux > transition read might be a way to cut down on the number of reads.
Bear in mind that the datarate of a ST506 MFM hard drive is 5MHz, as opposed to 500KHz for an 8" MFM floppy, so the sample clock may have to run quite a bit faster--should not be a problem on any modern MCU. But also note that the data lines to the drive are *differential* not single-ended, so you'll also need RS422 receivers as well as proper termination. FWIW, Chuck
