8. 勾选Create HEX File
9. 编译链接，产生hex文件。
10. 下载到开发板上运行。
11. 运行结果
/*************************************************************************/ /* 本程序精炼自STM32官方固件库，留下必要的代码，并做了详细说明 */ /*************************************************************************/ /* 定义时钟结构体 */
typedef struct {
volatile unsigned int CR; volatile unsigned int CFGR; volatile unsigned int CIR;
volatile unsigned int APB2RSTR; volatile unsigned int APB1RSTR; volatile unsigned int AHBENR; volatile unsigned int APB2ENR; volatile unsigned int APB1ENR; volatile unsigned int BDCR; volatile unsigned int CSR; volatile unsigned int AHBRSTR; volatile unsigned int CFGR2;
} RCC_TypeDef;
/* 定义时钟结构体的指针变量 */
#define RCC ((RCC_TypeDef *)0x40021000)
/* memory mapped structure for System Control Block (SCB) */ typedef struct {
volatile unsigned int CPUID; volatile unsigned int ICSR;
volatile unsigned int VTOR; /* 存放中断向量表的起始地址的寄存器 */ volatile unsigned int AIRCR; volatile unsigned int SCR; volatile unsigned int CCR; volatile unsigned int SHP[12]; volatile unsigned int SHCSR; volatile unsigned int CFSR; volatile unsigned int HFSR; volatile unsigned int DFSR; volatile unsigned int MMFAR; volatile unsigned int BFAR; volatile unsigned int AFSR; volatile unsigned int DFR; volatile unsigned int ADR; volatile unsigned int MMFR[4]; volatile unsigned int ISAR[5];
} SCB_Type; #define SCB ((SCB_Type *)0xE000ED00) /* 定义对应结构体指针变量 */
/* 定义GPIO结构体 */
typedef struct {
volatile unsigned int CRL; /*配置寄存器GPIOx_CRL，偏移地址00*/ volatile unsigned int CRH; /*配置寄存器GPIOx_CRH，偏移地址04*/ volatile unsigned int IDR; /*数据寄存器GPIOx_IDR， 偏移地址08 */ volatile unsigned int ODR; /*数据寄存器GPIOx_ODR，偏移地址0C*/ volatile unsigned int BSRR; /*置位寄存器GPIOx_BSRR， 偏移地址10*/ volatile unsigned int BRR; /*复位寄存器GPIOx_BRR，偏移地址14*/ volatile unsigned int LCKR; /*锁定寄存器GPIOx_LCKR，偏移地址18*/ } GPIO_TypeDef;
/* 定义GPIO结构体指针变量 */
#define GPIOD ((GPIO_TypeDef *)0x40011400)
/*************************************************************************/ /* main函数 */ /*************************************************************************/ int main(void) {
/* 初始化系统时钟 */
RCC->CR |= (unsigned int)0x00000001; RCC->CFGR &= (unsigned int)0xF8FF0000; RCC->CR &= (unsigned int)0xFEF6FFFF; RCC->CR &= (unsigned int)0xFFFBFFFF; RCC->CFGR &= (unsigned int)0xFF80FFFF; RCC->CR &= (unsigned int)0xEBFFFFFF; RCC->CIR = 0x00FF0000; RCC->CFGR2 = 0x00000000; /* Vector Table Relocation in Internal SRAM.*/ SCB->VTOR = ((unsigned int)0x20000000); /* 打开GPIOD口时钟 */
RCC->APB2ENR |= 0x20;
/* 设置GPIOD第2脚为推挽输出模式，速率为50MHz */ GPIOD->CRL &= 0xFFFFF0FF; GPIOD->CRL |= 0x00000300; /* 点亮PD2口的LED */ GPIOD->BRR &= 0xFFFFFFFB; while (1) { }
}
/**************************** *****END OF FILE**********************/
STM32启动代码分析、简化、实战
