Changes
765 FDC
,/* MFM Encoding */
=== MFM Encoding ===
MFM, or Modified Frequency Modulation, was developed as a more efficient alternative to FM encoding. The core idea behind MFM is to reduce the number of magnetic transitions needed to represent data, thereby allowing more information to be stored in the same amount of space.
In MFM, clock pulses are not always present. Instead, a clock pulse only occurs between two consecutive 0s. If a 1 appears, it doesn’t need a clock pulse to mark it; instead, a transition is placed in the middle of the bit cell to represent the 1. Additionally, when a 0 follows a 1, no transition is needed, further minimizing the number of magnetic changes.
This method greatly reduces the number of transitions needed to represent data compared to FM, allowing MFM to store significantly more data in the same space.
[[File:MFM encoding scheme.png|600px]]