X-Nico

2 unusual facts about Modified Frequency Modulation


Modified Frequency Modulation

--Machines using CP/M is likely to use MFM, but CP/M itself has nothing to do with MFM--> machines as well as IBM PC compatibles.

Seagate Technology

The hard disk, which used a Modified Frequency Modulation (MFM) encoding, was a hit, and was later released in a 10-megabyte version, the ST-412, with which Seagate secured a contract as a major OEM supplier for the IBM XT, IBM's first personal computer to contain a hard disk.


SuperDrive

This was made possible as the SuperDrive now utilitized the same MFM (Modified Frequency Modulation) encoding scheme used by the IBM PC, yet still retained backward compatibility with Apple's variable-speed zoned CAV scheme and Group Code Recording encoding format, so it could continue to read Macintosh MFS, HFS and Apple II ProDOS formats on 400/800 KB disks.


see also