说明：  STM32f407是一种基于Cortex-M4的用于高端控制领域的单片机，功能强大！
(The ARM Cortex-M4F processor is the latest generation of ARM processors for embedded systems. It was developed to provide a low-cost platform that meets the needs of MCU implementation, with a reduced pin count and low-power consumption, while delivering outstanding computational performance and an advanced response to interrupts.)