On 11/28/19 9:34 PM, David Kuder via cctalk wrote: > After digging in the manual for the controller card, it appears they have set > it up to only support single density FM formatting. Even still, formatting > the disk 568KB FM with either clock speed 8MHz or 4MHz (and 500KHz / 250KHz > WCLK respectively), same outcome with missing address mark. I think I’m > going to scrap the floppy card and design a fresh one using the FDC37C78. > Less things to go wrong.
Is there a manual for the card online? If you're doing your own, I'd recommend a NSC DP8473--it has the benefit of full FM and MFM support, including reading and writing 128 byte MFM data. Not even the NSCPC8477 can do that--and you can forget the Intel chips like the 82077/78 for FM. --Chuck
