Control system and method for multiple rate disk drive data transfer with a single oscillator

摘要

A computer disk drive control adapts the rate of data transfer between a disk drive and a CPU to correspond to one of three industry standard transfer rates. The timing of disk controller signals is provided for by a two phase state machine that receives a signal representative of a selected data transfer rate and generates disk controller signals of the appropriate frequency and configuration. Such disk controller signals cause a disk controller to effect data transfer at the selected rate. In a preferred embodiment, the two phase state machine is driven by two opposite phases of a single 24 MHz clock.