Method for controlling electro-mechanical devices

In a microprocessor-controlled apparatus a plurality of event vector tables and a plurality of event action blocks are defined and stored in memory to provide a determined set of actions to be performed in correspondence to activation by respective determined events. A profile interpreter processes action function sequences from these tables and commands the corresponding actions, sets a corresponding event-occurred flag and thereafter commands other actions and manipulates the flag by operation of respective profile action functions associated with the respective operations of the apparatus. The levels of operation may be arranged hierarchically so that additional modules may be added at a lower level without altering the control functions provided at the higher level. All of the primitive functions that can be realistically supported by the device controller are preferably included in the base software. Aggregate functions may be designed to support complex I/O functions such as scanning. In accordance with the invention these functions are activated by device profiles that are downloaded by the system software to each device controller during application initialization. These profiles can also be hard-coded into a source-format include-file to accommodate a standalone operation without download capability. Mailpiece tracking is included in the method.