Archiving CP/M 2.2 Source Code Programs to a PC (Fat or NTFS media)

Eric Smith spacewar at
Fri Jan 15 16:00:12 CST 2016

On Jan 15, 2016 8:32 AM, "Robo58" <robo58 at> wrote:
> The 8" SD diskettes are standard IBM format (I
> believe 3740 physical format) 26 sectors.

Almost all SD 8 inch use that physical format, though there are some
oddball formats like OSI.

Similarly almost all 8 inch SD CP/M disks use the same logical (filesystem)
format, because that was THE standard for CP/M interchamge.

>  I believe the  8" DD follows the
> same 3740 physical format

3740 is specifically SD. By definition, DD *must* be a different physical
format. In most cases, DD uses IBM System/34 format, though as with SD
there are some oddballs. The big problem is that there is no standard for
CP/M logical format on DD (or a zillion "standards", depending on your

Usually when I've been faced with an unknown CP/M format, I've figured it
out "by hand" using a sector editor, because back then I didn't have any of
the fancy interchange programs that were sold.

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