stm32筆記:按鍵輸入(精簡版)

C代碼

//GPIOA8是LED0

//GPIOA13是KEY0僅包含啟動代碼STM32F10x.s

#defineGPIOA_CRL(*(volatileunsignedlong*)(0x40000000+0x10000+0x0800+0x00))

#defineGPIOA_CRH(*(volatileunsignedlong*)(0x40000000+0x10000+0x0800+0x04))

#defineGPIOA_IDR(*(volatileunsignedlong*)(0x40000000+0x10000+0x0800+0x08))

#defineGPIOA_ODR(*(volatileunsignedlong*)(0x40000000+0x10000+0x0800+0x0C))

#defineRCC_APB2ENR(*(volatileunsignedlong*)(0x40000000+0x20000+0x1000+0x18))

voiddelay(unsignedlongi)//超級不精確的軟延時(shí)

{

intj;

while(i--)

{

for(j=0;j<1500;j++)

{}

}

}

intmain(void)

{

u8keyflag=1;//按鍵進(jìn)入標(biāo)志,防止一次按鍵多次判斷的簡易做法

RCC_APB2ENR=1<<2;//打開PA時(shí)鐘,默認(rèn)啟用內(nèi)部8M時(shí)鐘

GPIOA_CRH&=0XFFFFFFF0;//準(zhǔn)備配置PA8,PA8是LED0

GPIOA_CRH|=0X00000003;//PA8推挽輸出

GPIOA_ODR|=1<<8;//PA8輸出高,即先關(guān)閉led

GPIOA_CRH&=0XFF0FFFFF;//準(zhǔn)備配置PA13,PA13是KEY0

GPIOA_CRH|=0X00800000;//配置PA13為帶上拉下拉輸入

while(1)

{

if(!checkBit(GPIOA_IDR,13))//鍵被按下的話,執(zhí)行l(wèi)ed反轉(zhuǎn)

{

if(keyflag)

{

keyflag=0;

GPIOA_ODR=revBit(GPIOA_ODR,8);//第8位反轉(zhuǎn),revBit是宏

}

}

else

{

keyflag=1;

}

delay(10);//簡易消抖

}

}

//checkBit和revBit都是關(guān)于位的宏

//#defineBIT(n)(1<<(n))

//#definerevBit(val,n)((val)^(BIT(n)))

//#definecheckBit(val,n)(((val)&(BIT(n)))>>(n))