MICROPROCESSOR CIRCUITS AND SYSTEMS WITH LIFE SPANNED STORAGE CIRCUIT FOR STORING NON-CACHEABLE DATA

A microprocessor (5) for coupling to an external read/write memory (20) having an addressable storage space. This storage space stores cacheable digital data and non-cacheable (32) digital data. The microprocessor includes a data storage circuit (62) for storing a portion of the non-cacheable data. The microprocessor further includes an address storage circuit (64) for storing an address corresponding to the portion of the non-cacheable data. Still further, the microprocessor includes a counter (72) for advancing a count from an initial value (74) toward a threshold value (76) in response to an activity over time. The counter initiates its advancing operation in response to the data storage circuit receiving the portion of the non-cacheable data. Lastly, the microprocessor includes an indicator (66) for indicating the portion of the non-cacheable data in the data storage circuit is expired in response to the count reaching a threshold.