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STM8S---外部中断应用之长按键识别

发布时间:2020-06-18 发布时间:
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STM8常用中断指令

  • 开总中断 

    • _asm(“rim”);

  • 禁止中断 

    • _asm(“sim”);

  • 进入停机模式 

    • _asm(“halt”);

  • 中断返回 

    • _asm(“iret”);

  • 等待中断 

    • _asm(“wfi”);

  • 软件中断 

    • _asm(“trap”);

STM8S常用中断映射

如使用中断函数时,可以通过在上图中查找相对应的中断向量号,而中断函数的名字可以自定义

/*  BASIC INTERRUPT VECTOR TABLE FOR STM8 devices

 *  Copyright (c) 2007 STMicroelectronics

 */


typedef void @far (*interrupt_handler_t)(void);


struct interrupt_vector {

    unsigned char interrupt_instruction;

    interrupt_handler_t interrupt_handler;

};


@far @interrupt void NonHandledInterrupt (void)

{

    /* in order to detect unexpected events during development, 

       it is recommended to set a breakpoint on the following instruction

    */

    return;

}


extern void _stext();     /* startup routine */

extern @far @interrupt void EXTI2_Hand_Fun(void);

extern @far @interrupt void TIM1_UPD_OVF_TRG_BRK_IRQHandler(void);



struct interrupt_vector const _vectab[] = {

    {0x82, (interrupt_handler_t)_stext}, /* reset */

    {0x82, NonHandledInterrupt}, /* trap  */

    {0x82, NonHandledInterrupt}, /* irq0  */

    {0x82, NonHandledInterrupt}, /* irq1  */

    {0x82, NonHandledInterrupt}, /* irq2  */

    {0x82, NonHandledInterrupt}, /* irq3  */

    {0x82, NonHandledInterrupt}, /* irq4  */

    {0x82, EXTI2_Hand_Fun}, /* irq5  */

    {0x82, NonHandledInterrupt}, /* irq6  */

    {0x82, NonHandledInterrupt}, /* irq7  */

    {0x82, NonHandledInterrupt}, /* irq8  */

    {0x82, NonHandledInterrupt}, /* irq9  */

    {0x82, NonHandledInterrupt}, /* irq10 */

    {0x82, TIM1_UPD_OVF_TRG_BRK_IRQHandler}, /* irq11 */

    {0x82, NonHandledInterrupt}, /* irq12 */

    {0x82, NonHandledInterrupt}, /* irq13 */

    {0x82, NonHandledInterrupt}, /* irq14 */

    {0x82, NonHandledInterrupt}, /* irq15 */

    {0x82, NonHandledInterrupt}, /* irq16 */

    {0x82, NonHandledInterrupt}, /* irq17 */

    {0x82, NonHandledInterrupt}, /* irq18 */

    {0x82, NonHandledInterrupt}, /* irq19 */

    {0x82, NonHandledInterrupt}, /* irq20 */

    {0x82, NonHandledInterrupt}, /* irq21 */

    {0x82, NonHandledInterrupt}, /* irq22 */

    {0x82, NonHandledInterrupt}, /* irq23 */

    {0x82, NonHandledInterrupt}, /* irq24 */

    {0x82, NonHandledInterrupt}, /* irq25 */

    {0x82, NonHandledInterrupt}, /* irq26 */

    {0x82, NonHandledInterrupt}, /* irq27 */

    {0x82, NonHandledInterrupt}, /* irq28 */

    {0x82, 



NonHandledInterrupt}, /* irq29 */

};


外部中断长按键识别相关配置

  STM8S为外部中断事件专门分配了五个中断向量:

  • PortA 口的5个引脚:PA[6:2]

  • PortB 口的8个引脚:PB[7:0]

  • PortC 口的8个引脚:PC[7:0]

  • PortD 口的7个引脚:PD[6:0]

  • PortE口的8个引脚:PE[7:0]

  PD7是最高优先级的中断源(TLI);

中断IO设置

  这里选用EXTI2(端口C外部中断)。那么需要将中断促发的IO(PC5)设置为上拉输入或中断上拉输入,悬浮输入的话很容易受干扰。


/*PC5设置为上拉输入*/void Init_EXTI2_GPIO(void) {    PC_DDR &= 0XDF;    PC_CR1 &= 0XDF;    PC_CR2 |= 0x20; }


外部中断寄存器配置

CPU CC寄存器中断位:12

  I1 I0不能直接写,只能通过开中断或关中断来写,上电默认是11;当用指令开中断时( _asm(“rim\n”);),为00;当发生中断时,由当前中断(ITC_SPRx)载入I[1:0],主要用于做中断优先级;退出中断自动清0;因此在写EXTI_CR1,需将ITC_SPRx配置成11,或加入禁中断指令 。

EXTI_CR1:12

  配置促发方式;


#include


char keyFlag;       

char keyPressStatus = 1;

unsigned int keyCount;      


/*Output Pin*/

_Bool PD2 @PD_ODR:2;

_Bool PC7 @PC_ODR:7;

_Bool PC6 @PC_ODR:6;

_Bool PC3 @PC_ODR:3;

/*Input Pin*/

_Bool PC5   @PC_IDR:5;


/*电量指示灯*/

#define LED1 PD2

#define LED2 PC7

#define LED3 PC6

#define LED4 PC3

/*按键*/

#define KEY     PC5



/*主时钟频率为8Mhz*/

void Init_CLK(void)

{

    CLK_ICKR |= 0X01;           //使能内部高速时钟 HSI

    CLK_CKDIVR = 0x08;          //16M内部RC经2分频后系统时钟为8M

    while(!(CLK_ICKR&0x02));    //HSI准备就绪 

    CLK_SWR=0xE1;               //HSI为主时钟源 

}


void Init_LED(void)

{

    /*LED 配置为推挽输出*/

    PD_DDR |= 0X04;   //PD2输出模式,0为输入模式

    PD_CR1 |= 0X04;   //PD2模拟开漏输出

    PD_CR2 &= 0XFB;   //PD2输出速度最大为2MHZ,CR1/CR2悬浮输入


    PC_DDR |= 0XC8;

    PC_CR1 |= 0XC8;

    PC_CR2 &= 0X27;

}


/*PC5设置为上拉输入*/

void Init_EXTI2_GPIO(void)

{


    PC_DDR &= 0XDF; 

    PC_CR1 &= 0XDF;

    PC_CR2 |= 0X20;

}


void Init_EXTI2(void)

{

    EXTI_CR1 |= 0x30;       //上升沿和下降沿促发

}



void Init_TIM1(void)

{

    TIM1_IER = 0x00;

    TIM1_CR1 = 0x00;


    TIM1_EGR |= 0x01;

    TIM1_PSCRH = 199/256; // 8M系统时钟经预分频f=fck/(PSCR+1) TIM1 为16位分频器 

    TIM1_PSCRL = 199%256; // PSCR=0x1F3F,f=8M/(200)=40000Hz,每个计数周期1/40000ms


    TIM1_CNTRH = 0x00;

    TIM1_CNTRL = 0x00;      


    TIM1_ARRH = 400/256;  // 自动重载寄存器ARR=400

    TIM1_ARRL = 400%256;  // 每记数400次产生一次中断,即10ms


    TIM1_CR1 |= 0x81;

    TIM1_IER |= 0x01;

}


unsigned int Key_Scan_Test(void)

{

    unsigned int count = 0;

    unsigned char keyMode;


    if(0 == keyPressStatus)

    {

        keyFlag = 1;

        while(!keyPressStatus);

        keyFlag = 0;

        count = keyCount;

        keyCount = 0;

    }

    else

    {

        count = 0;

    }

    /*10ms * 150 = 1.5s*/

    if(count >= 150)keyMode = 2;        //长按

    else if(count >= 4)keyMode = 1;     //短按

    else keyMode = 0;                   //抖动


    return keyMode;

}


main()

{  

    char keynum = 0;


    _asm("sim");

    Init_CLK();

    Init_LED();

    Init_EXTI2_GPIO();

    Init_EXTI2();

    Init_TIM1();

    _asm("rim");

    while (1)

    {

        keynum = Key_Scan_Test();

        if(1 == keynum)LED3 = ~LED3;

        if(2 == keynum)LED4 = ~LED4;

    }

}


@far @interrupt void EXTI2_Hand_Fun(void)

{

    keyPressStatus = !keyPressStatus;

    LED1 = ~LED1;

}


@far @interrupt void TIM1_UPD_OVF_TRG_BRK_IRQHandler(void)

{

    static unsigned int i = 0;


    TIM1_SR1 &= ~(0X01);


    ++i;

    if(50 == i)

    {

        LED2 = ~LED2;

        i = 0;

    }


    /*Within Key Press Hand*/

    if(1 == keyFlag)

    {

        ++keyCount;

    }

}


注意: 中断向量需声明,在stm8_interrupt_vector.c中加入: extern @far @interrupt void EXTI2_Hand_Fun(void); extern @far @interrupt void TIM1_UPD_OVF_TRG_BRK_IRQHandler(void); {0x82, EXTI2_Hand_Fun}, /* irq5  */ {0x82, TIM1_UPD_OVF_TRG_BRK_IRQHandler}, /* irq11 */

 

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