自主MCU外設(shè)提供嵌入式設(shè)計，具有許多功能。

　　從微處理器的主處理器中卸下許多常規(guī)任務(wù)的自治外圍內(nèi)核，在提高嵌入式處理器實時性的同時，也大大降低了能耗。目前可供選擇的幾種流行的MCU架構(gòu)的變種，這些所謂的“智能設(shè)備”是專用的硬件元素，可以單獨或與其它核來完成復(fù)雜的數(shù)據(jù)采集，I / O，和管家功能，CPU處于低功耗的睡眠模式。除了巨大的功率節(jié)省之外，這些智能外設(shè)提供了對實時事件的確定性響應(yīng)，而不需要復(fù)雜的中斷服務(wù)例程或RTOS軟件。在本文中，我們將介紹能源微（圖1）和Atmel最近推出的智能外設(shè)系統(tǒng)的體系結(jié)構(gòu)細(xì)節(jié)，它們的8位和32位平臺以及它們在實際應(yīng)用中提供的一些優(yōu)勢。

　　Figure 1： This cargo container monitor relies on the autonomous peripherals in Energy Micro’s EFM32 MCU to help it provide shippers with location and status data for a year or more on a single set of batteries. The monitor mounts on a standard shipping container’s main door and uses the EFM32’s compliment of autonomous peripherals to handle routine data collection （GPS coordinates， temperature， shock/vibration， door openings， and tamper detection） while the CPU spends nearly all of its time in a low-power sleep state. （Courtesy of Starcom Systems.）

　　Intelligent evolution

　　Intelligent peripherals are a natural extension of the I/O controllers， algorithmic accelerators， and other specialized hardware modules already used in many MCUs. Today， even many low-cost 8-bit microcontrollers such as Microchip Technology’s PIC18 or STMicro’s STM8 family include specialized state machines or accelerator cores， which offload tasks such as matrix operations， encryption， error correction， or controlling a touch screen. Nevertheless， the accelerator modules， screen controllers， and other I/Os all rely on the main processor （CPU） for one or more aspect of their operation， and often compete with it for access to the memory bus and other shared resources. In contrast， autonomous peripherals only require the CPU when they are being initialized and configured to perform a particular set of functions and， in most cases， communicate using a separate bus.