METHOD AND APPARATUS FOR CONTROLLING A DATA PROCESSING SYSTEM DURING DEBUG

摘要

A data processing system (10) includes a debug unit (14) that is capable of providing unobtrusive debug capabilities to the normal operation of the data processing system by controlling activation of all or a selected subset of a plurality of subsystems as needed for a debug operation. For example, power can be conserved by activating selected subsystems as needed for a debug operation. Furthermore, in one embodiment, the debug unit provides a level of activation, ranging from deactivation to full activation, to the selected subsystems which provides further control of the data processing system. In one embodiment, debug control and status registers (40) are provided for power management handshaking between the debug unit and the plurality of subsystems. The handshaking can be used to ensure that a debug operation may proceed properly since the selected subsystems are capable of providing status information to the debug unit.