The family of 32-bit flash microcontrollers based on the ARM Cortex-M3 core—a core with features specifically designed for embedded applications requiring a combination of high performance (1.25 Dhrystone MIPS/MHz)—is designed to offer low power consumption and low cost. The microcontroller family benefits from the Cortex-M3’s architectural enhancements, including the Thumb-2 instruction set to deliver improved performance combined with better code density, and a tightly coupled nested vectored interrupt controller for faster response to interrupt, all combined with industry-leading power consumption. It is designed to deliver performance and energy efficiency while retaining the benefits of the open, industry-standard ARM architecture and development environment. The microcontroller is offered in two lines: the STM32F103 Performance line, with 72-MHz clock frequency, provides 32-bit MCU performance, while the STM32F101 Access line, with 36-MHz clock frequency, offers users a significant increase in performance at the same 16-bit price levels. Both lines offer from 32 to 128 K of embedded Flash memory but differ in maximum SRAM size and peripheral combinations. At 72 MHz, executing from Flash, the STM32 consumes only 36 mA, the lowest power consumption in the 32-bit market, corresponding to an impressive 0.5mA/MHz.