:3. How to determine the actual rate. The NEC765 floppy disc controller is supplied with a single clock. When reading from and writing to a disc using the NEC765 you can choose FM or MFM recording modes. Use of these modes and the clock into the NEC765 define the final rate at which the data is written to the disc.
:When FM recording mode is used, data is read from or written to at a rate which is double that of when MFM is used. The time for each bit will be twice the time for MFM.
:Also, the actual rate is twice longer that of the datasheet as the NEC765 clock is 4MHz on CPC instead of 8MHz for the datasheet.
:Examples: