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

Chuck Guzis cclist at
Fri Jan 15 16:56:09 CST 2016

On 01/15/2016 02:00 PM, Eric Smith wrote:
> 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 attribute that to the lack of user low-level formatting software.

In general, they do follow the A1 format, but there were a couple, such 
as the HP 125 to ruin your day.  Once you migrate to MFM, standard 
formats simply don't exist.  Even IBM had several different MFM 8" formats.

No one's touched on hard-sector formats, which could really get bizarre, 
such as the Zilog MCZ format with 132-byte sectors.  Or clever things 
like RX02 and "weird MFM" or various GCR schemes (e.g. Future Data). 
Fortunately, few hobbyists run into those.


More information about the cctalk mailing list