System for extending functionality of a digital ROM using RAM/ROM jump tables and patch manager for updating the tables

摘要: A system and method for extending the functionality of a digital is disclosed. The includes read-only memory (ROM) storing an extendible control application, processing unit executing code stored in ROM, imaging device capturing optical images converting them to code, random-access (RAM) providing working storage files images, input-output (I/O) receiving user input communicating with host computer transfer files, optional removable means introducing extensions into system. ROM image patch manager function pointers which, together, permit redirection program execution sequence. New pieces (extensions) can, through such redirection, be incorporated original, non-modifiable supplement or replace routines original application.