Microcontrollers with real-time advantages

摘要

You can make the most powerful CPU possible, but if you can't connect to the outside world efficiently, it's all for naught. This is especially true for real-time systems that can't afford to wait around to get bytes out. Some processor folks have implemented what's often called event management. This takes the communication load off of the CPU, normally driven by an interrupt. That interrupt usually takes on the order of 20 to 50 clock cycles; by the time the processor saves the context for a limited number of registers, accesses a peripheral, saves the data, restores the context, and perhaps deals with a pipeline flush.