Multiplexed status and diagnostic pins in a microprocessor with on-chip caches

摘要

In a microprocessor, two output pins are dedicated to providing information to assist in diagnosing problems relating to internal instruction and data caches or the software executing in the caches. The information on the pins is time-multiplexed. In a first phase, the pins indicate whether the data or instruction cache is accessed and whether a cache miss has occurred. In a second phase, the pins carry signals identifying the address reference which resulted in a cache miss.