1. An apparatus providing for a secure execution environment, comprising: a microprocessor, configured to execute non-secure application programs and a secure application program, wherein said non-secure application programs are accessed from a system memory via a system bus, and wherein said secure application program is executed in a secure execution mode, said microprocessor comprising: secure watchdog logic, configured to monitor environmental attributes corresponding to said microprocessor and to said secure application program, and configured to transfer program control to one of a plurality of event handlers within said secure application program; and a secure non-volatile memory, coupled to said microprocessor via a private bus, configured to store said secure application program, wherein transactions over said private bus between said microprocessor and said secure non-volatile memory are isolated from said system bus and corresponding system bus resources within said microprocessor.