On Thu, 3 Nov 2022, Paul Koning via cctalk wrote:
An example of a non-PC format 5.25 inch disk that normal drives can read would be the DEC RX50 floppy, which has 10 sectors per track rather than the PC standard 9 sectors. But a standard drive will read and write those just fine, if it's told to use that format. I did that ages ago in DOS, but in the past 15 years or so I've only used Linux for that job. It's a simple matter, you just need to know what the format is.
'course MS-DOS/PC-DOS/WINDOWS can't understand anything other than its own very limited selection of formats. Does Windoze 11 still understand the original 160K format of PC-DOS 1.00?
It helps to be using a program that can talk to the BIOS, or directly to the FDC, to be able to use the other sector sizes, and file systems.
But, with a little programming, such as dropping down to BIOS level, and calling INT13h, you can read most others that use IBM/Western Digital sector and track structures (generally becaause they used a WD or NEC FDC) http://www.xenosoft.com/fmts.html is a list of some of the ones that I implemented in XenoCopy-PC
-- Grumpy Ol' Fred ci...@xenosoft.com
