《introToCortex-M3》.pdfVIP

An Introduction to the ARM Cortex-M3 Processor Shyam Sadasivan October 2006 1. Introduction System-on-chip solutions based on ARM embedded processors address many different market segments including enterprise applications, automotive systems, home networking and wireless technologies. The ARM Cortex™ family of processors provides a standard architecture to address the broad performance spectrum required by these diverse technologies. The ARM Cortex family includes processors based on the three distinct profiles of the ARMv7 architecture; the A profile for sophisticated, high-end applications running open and complex operating systems; the R profile for real-time systems; and the M profile optimized for cost-sensitive and microcontroller applications. The Cortex-M3 processor is the first ARM processor based on the ARMv7-M architecture and has been specifically designed to achieve high system performance in power- and cost-sensitive embedded applications, such as microcontrollers, automotive body systems, industrial control systems and wireless networking, while significantly simplifying programmability to make the ARM architecture an option for even the simplest applications. 1.1 Higher performance through better efficiency In order to achieve higher performance, processors can either work hard or work smart. Pushing higher clock frequencies may increase performance but is also accompanied by higher power consumption and design complexity. On the other hand, higher compute efficiency at slower clock speeds results in simpler and lower power designs that can perform the same tasks. At the heart of the Cortex-M3 processor is an advanced 3-stage pipeline core, based on the Harvard architecture, that incorporates many new powerful features such as branch speculation, sing