Modular disc drive architecture

A data storage device comprising:

• a data storage disc;
• an actuator assembly adjacent the disc including a read/write head, the actuator assembly being operable to position over the data storage disc;
• and
• a data storage device controller operably connected to the actuator assembly, comprising:
• a microprocessor;
• computer readable medium;
• a plurality of non-preemptive operating modules, each of the non-preemptive operating modules comprising microprocessor executable code operable to control a process within the data storage device controller;
• a scheduler comprising microprocessor executable code stored on the computer readable medium, the scheduler scheduling the order in which the microprocessor executes the non-preemptive operating modules;
• and
• a plurality of preemptive operating modules stored on the computer readable medium, each of the preemptive operating modules comprising microprocessor executable code operable to control a process within the data storage device controller, the preemptive operating modules being operable to preempt the operation of the scheduler and the non-preemptive operating modules.

A disc drive control module for controlling operational processes in a disc drive, comprising:

• a plurality of non preemptive modules, each non-preemptive module comprising at least one action, each action being operable to control a process within the disc drive;
• a plurality of next module indicators, each next module indicator being associated with a respective non-preemptive module, each next module indicator indicating the non-preemptive module which is to be executed after the completion of its associated non-preemptive module;
• a plurality of next action indicators, each next action indicator being associated with a respective non-preemptive module, each next action indicator indicating an action to be executed upon the launch of its respective non-preemptive module;
• and
• a scheduler module operable to launch the non-preemptive modules and execute the actions, the scheduler module launching the non-preemptive modules in an order related to the next module indicators of the non-preemptive modules, the scheduler module, upon launch of a non-preemptive modules, executing the action indicated by the next action indicator associated with the launched non-preemptive module;
• and
• a plurality of preemptive operating modules, each of the preemptive operating modules operable to control a process within the disc drive, each of the preemptive operating modules being operable to preempt the operation of the scheduler module and the cooperative operating modules.