说明：  关于APP程序的中断向量表地址偏移（三种方法，stm32F2与F4系列通用。三种方法本质一样只是 各种例程的表现形式不一样）
(On the APP program interrupt vector table address offset (three methods, stm32F2 and F4 series common.Three methods are essentially the same as the various forms of expression are not the same))