METHOD AND APPARATUS FOR AUTOMATIC SECTOR PULSE GENERATION AND SPLIT FIELD CALCULATION IN DISK DRIVES

摘要

A method and apparatus for automatic sector pulse generation and split field calculation in disk drives without the use of tables improves the seek latency of a disk drive system because it does not have to wait for the INDEX mark or the beginning of a frame, before beginning an operation it has been instructed to perform. The system can be designed to start from any point on the disk and begin calculations as if it were starting from the INDEX mark or the beginning of a frame. The calculations performed for each servo mark calculate the number of sectors and split fields which can be stored between servo marks on the disk. Multiple calculations can be performed between to servo marks. A counter is used to keep track of the number of servo marks for which the system has performed calculations. This counter is compared to the number of the last previously detected servo mark. The system continues to perform the calculations for each servo mark until the counter is equal to the number of the previously passed servo mark. At this point the system is synchronized and can perform the operation that it was instructed to perform, either format, read or write. The system can also be instructed to wait for the INDEX mark or the beginning of the next frame if the system is not compatible with the fast forward method.