① 時鐘系統(tǒng)：

? ??????????????時鐘源 — >外部晶振

????????????????鎖相環(huán) ： 倍頻 + 分頻

? ? ? ? ? ? ? ? AHB（關(guān)注AHB1），APB（關(guān)注APB1，APB2）

② 總線

????????????????AMBA : AHB( 高速總線 ) + APB（外設(shè)總線）

③ 時鐘樹

④ 任務(wù)：使用按鍵控制輸入輸出

????????????????PA0低電平 未按下 ??高電平 按下

????????????????//PA0硬件初始化

????????????????時鐘源打開

????????????????配置PA0

????????????????輸入

????????????????上拉/下拉

????????????????應(yīng)用

????????????????輸入數(shù)據(jù)寄存器采樣（while下 輪訓(xùn) 此寄存器 ）

? ? ? ? 代碼：

#include<stdio.h>

#define? Time_Delay 5000

#define RCC_ADDR 0x40023800

#define RCC_AHB1ENR ? *((unsigned int *)(RCC_ADDR+0x30))

#define GPIOA_ADDR 0x40020000

#define GPIOA_IDR *((unsigned int *)(GPIOA_ADDR + 0x10))

#define GPIOC_ADDR 0x40020800

#define GPIOC_IDR *((unsigned int *)(GPIOC_ADDR + 0x10))

#define GPIOH_ADDR 0x40021C00

#define GPIOH_MODER *((unsigned int *)(GPIOH_ADDR + 0x00))

#define GPIOH_OTYPER *((unsigned int *)(GPIOH_ADDR + 0x04))

#define GPIOH_OSPEEDER *((unsigned int *)(GPIOH_ADDR + 0x08))

#define GPIOH_PUPDR *((unsigned int *)(GPIOH_ADDR + 0x0C))

#define GPIOH_ODR *((unsigned int *)(GPIOH_ADDR + 0x14))

#define GPIOI_ADDR 0x40022000

#define GPIOI_MODER *((unsigned int *)(GPIOI_ADDR + 0x00))

#define GPIOI_OTYPER *((unsigned int *)(GPIOI_ADDR + 0x04))

#define GPIOI_OSPEEDER *((unsigned int *)(GPIOI_ADDR + 0x08))

#define GPIOI_PUPDR *((unsigned int *)(GPIOI_ADDR + 0x0C))

#define GPIOI_ODR *((unsigned int *)(GPIOI_ADDR + 0x14))

int k=0;

int i[7]={1,2,3,4,5,6,7};

void delay(unsigned int n)

{

unsigned int i,j;

for(i=0;i<n;i++)

for(j=0;j<1000;j++);

}

void Beep()

{

GPIOI_MODER = 0x400000;

GPIOI_OTYPER = 0x00;

GPIOI_PUPDR = 0x400000;

GPIOI_OSPEEDER = 0x00;

GPIOI_ODR = 0x800;

delay(Time_Delay);

GPIOI_ODR = 0x00;

}

void Red()

{

GPIOH_MODER = 0x100000; //ê?3?

GPIOH_OTYPER = 0x00; //í?íì

GPIOH_PUPDR = 0x100000; //é?à-

GPIOH_OSPEEDER = 0x00; //μí?ù

GPIOH_ODR = 0x00; //μí

// Beep();

// GPIOH_ODR = 0x400; //??

// delay(Time_Delay);

}

void Yellow()

{

GPIOH_MODER = 0x500000;

GPIOH_OTYPER = 0x00;

GPIOH_PUPDR = 0x500000;

GPIOH_OSPEEDER = 0x00;

GPIOH_ODR = 0x00;

// Beep();

// GPIOH_ODR = 0xC00;

// delay(Time_Delay);

}

void Green()

{

GPIOH_MODER = 0x400000;

GPIOH_OTYPER = 0x00;

GPIOH_PUPDR = 0x400000;

GPIOH_OSPEEDER = 0x00;

GPIOH_ODR = 0x00;

// Beep();

// GPIOH_ODR = 0x800;

// delay(Time_Delay);

}

void Cyan()

{

GPIOH_MODER = 0x1400000;

GPIOH_OTYPER = 0x00;

GPIOH_PUPDR = 0x1400000;

GPIOH_OSPEEDER = 0x00;

GPIOH_ODR = 0x00;

// Beep();

// GPIOH_ODR = 0x1800;

// delay(Time_Delay);

}

void Blue()

{

GPIOH_MODER = 0x1000000;

GPIOH_OTYPER = 0x00;

GPIOH_PUPDR = 0x1000000;

GPIOH_OSPEEDER = 0x00;

GPIOH_ODR = 0x00;

// Beep();

// GPIOH_ODR = 0x1000;

// delay(Time_Delay);

}

void Purple()

{

GPIOH_MODER = 0x1100000;

GPIOH_OTYPER = 0x00;

GPIOH_PUPDR = 0x1100000;

GPIOH_OSPEEDER = 0x00;

GPIOH_ODR = 0x00;

// Beep();

// GPIOH_ODR = 0x1400;

// delay(Time_Delay);

}

void White()

{

GPIOH_MODER = 0x1500000;

GPIOH_OTYPER = 0x00;

GPIOH_PUPDR = 0x1500000;

GPIOH_OSPEEDER = 0x00;

GPIOH_ODR = 0x00;

// Beep();

// GPIOH_ODR = 0x1C00;

// delay(Time_Delay);

}

void Key_1()

{

if((GPIOA_IDR & 0x01) == 0x01)

{

while((GPIOA_IDR & 0x01) == 0x01)

{

switch(i[k])

{

case 1:Red();Beep();break;

case 2:Yellow();Beep();break;

case 3:Green();Beep();break;

case 4:Cyan();Beep();break;

case 5:Blue();Beep();break;

case 6:Purple();Beep();break;

case 7:White();Beep();

}

}

k++;

if(k == 7)

k=0;

}

else

{

switch(i[k])

{

case 2:GPIOH_ODR = 0x400;break;

case 3:GPIOH_ODR = 0xC00;break;

case 4:GPIOH_ODR = 0x800;break;

case 5:GPIOH_ODR = 0x1800;break;

case 6:GPIOH_ODR = 0x1000;break;

case 7:GPIOH_ODR = 0x1400;break;

case 1:GPIOH_ODR = 0x1C00;

}

}

}

void Key_2()

{

if((GPIOC_IDR & 0x2000) == 0x2000)

{

Red();

Beep();

Green();

Beep();

Blue();

Beep();

}

}

int main(void)

{

//ê1?üê±?ó?′

RCC_AHB1ENR = 0x00100185; //A,C,H,I

while(1)

{

Key_1();

}

}