STM32按键设计,通过内部中断实现2个按键控制系统8种以上功能
时间: 2024-05-06 18:18:31 浏览: 7
STM32按键设计可以通过内部中断实现多个按键控制系统多种功能。下面是一个基本的按键设计示例:
1. 硬件电路设计
首先,需要设计一个硬件电路来连接按键和STM32微控制器。可以使用外部上拉电阻将按键连接到STM32的GPIO引脚上。当按键按下时,GPIO引脚的电平将变为低电平。
2. 软件配置
接下来,在STM32的软件中配置GPIO引脚和中断,以便在按键按下时触发中断。可以使用STM32的CubeMX工具来生成初始化代码。
3. 中断处理程序
当按键按下时,将触发中断,并调用中断处理程序。在中断处理程序中,可以检查哪个按键被按下,并根据需要执行相应的操作。例如,可以使用一个状态机来实现多个按键控制系统多种功能。
4. 示例代码
以下是一个简单的示例代码,用于演示如何实现两个按键控制系统八种以上的功能:
```c
#include "stm32f4xx.h"
#define KEY1_PIN GPIO_PIN_0
#define KEY1_GPIO_PORT GPIOA
#define KEY2_PIN GPIO_PIN_1
#define KEY2_GPIO_PORT GPIOA
#define LED1_PIN GPIO_PIN_12
#define LED1_GPIO_PORT GPIOD
#define LED2_PIN GPIO_PIN_13
#define LED2_GPIO_PORT GPIOD
#define LED3_PIN GPIO_PIN_14
#define LED3_GPIO_PORT GPIOD
#define LED4_PIN GPIO_PIN_15
#define LED4_GPIO_PORT GPIOD
typedef enum {
STATE_IDLE,
STATE_LED1_ON,
STATE_LED1_OFF,
STATE_LED2_ON,
STATE_LED2_OFF,
STATE_LED3_ON,
STATE_LED3_OFF,
STATE_LED4_ON,
STATE_LED4_OFF,
} state_t;
volatile uint8_t key1_pressed = 0;
volatile uint8_t key2_pressed = 0;
volatile state_t state = STATE_IDLE;
void EXTI0_IRQHandler(void) {
if (EXTI_GetITStatus(EXTI_Line0) != RESET) {
EXTI_ClearITPendingBit(EXTI_Line0);
key1_pressed = 1;
}
}
void EXTI1_IRQHandler(void) {
if (EXTI_GetITStatus(EXTI_Line1) != RESET) {
EXTI_ClearITPendingBit(EXTI_Line1);
key2_pressed = 1;
}
}
void init_gpio(void) {
GPIO_InitTypeDef GPIO_InitStruct;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
GPIO_InitStruct.GPIO_Pin = KEY1_PIN | KEY2_PIN;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_InitStruct.GPIO_Pin = LED1_PIN | LED2_PIN | LED3_PIN | LED4_PIN;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOD, &GPIO_InitStruct);
}
int main(void) {
init_gpio();
EXTI_InitTypeDef EXTI_InitStruct;
NVIC_InitTypeDef NVIC_InitStruct;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource0);
EXTI_InitStruct.EXTI_Line = EXTI_Line0;
EXTI_InitStruct.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStruct.EXTI_Trigger = EXTI_Trigger_Falling;
EXTI_InitStruct.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStruct);
NVIC_InitStruct.NVIC_IRQChannel = EXTI0_IRQn;
NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0x00;
NVIC_InitStruct.NVIC_IRQChannelSubPriority = 0x00;
NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStruct);
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource1);
EXTI_InitStruct.EXTI_Line = EXTI_Line1;
EXTI_InitStruct.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStruct.EXTI_Trigger = EXTI_Trigger_Falling;
EXTI_InitStruct.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStruct);
NVIC_InitStruct.NVIC_IRQChannel = EXTI1_IRQn;
NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0x00;
NVIC_InitStruct.NVIC_IRQChannelSubPriority = 0x00;
NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStruct);
while (1) {
if (key1_pressed) {
key1_pressed = 0;
switch (state) {
case STATE_IDLE:
state = STATE_LED1_ON;
GPIO_SetBits(LED1_GPIO_PORT, LED1_PIN);
break;
case STATE_LED1_ON:
state = STATE_LED1_OFF;
GPIO_ResetBits(LED1_GPIO_PORT, LED1_PIN);
break;
case STATE_LED1_OFF:
state = STATE_LED2_ON;
GPIO_SetBits(LED2_GPIO_PORT, LED2_PIN);
break;
case STATE_LED2_ON:
state = STATE_LED2_OFF;
GPIO_ResetBits(LED2_GPIO_PORT, LED2_PIN);
break;
case STATE_LED2_OFF:
state = STATE_LED3_ON;
GPIO_SetBits(LED3_GPIO_PORT, LED3_PIN);
break;
case STATE_LED3_ON:
state = STATE_LED3_OFF;
GPIO_ResetBits(LED3_GPIO_PORT, LED3_PIN);
break;
case STATE_LED3_OFF:
state = STATE_LED4_ON;
GPIO_SetBits(LED4_GPIO_PORT, LED4_PIN);
break;
case STATE_LED4_ON:
state = STATE_LED4_OFF;
GPIO_ResetBits(LED4_GPIO_PORT, LED4_PIN);
break;
case STATE_LED4_OFF:
state = STATE_IDLE;
break;
}
}
if (key2_pressed) {
key2_pressed = 0;
switch (state) {
case STATE_IDLE:
state = STATE_LED1_OFF;
GPIO_ResetBits(LED1_GPIO_PORT, LED1_PIN);
break;
case STATE_LED1_ON:
state = STATE_IDLE;
break;
case STATE_LED1_OFF:
state = STATE_LED2_OFF;
GPIO_ResetBits(LED2_GPIO_PORT, LED2_PIN);
break;
case STATE_LED2_ON:
state = STATE_LED1_OFF;
GPIO_ResetBits(LED1_GPIO_PORT, LED1_PIN);
break;
case STATE_LED2_OFF:
state = STATE_LED3_OFF;
GPIO_ResetBits(LED3_GPIO_PORT, LED3_PIN);
break;
case STATE_LED3_ON:
state = STATE_LED2_OFF;
GPIO_ResetBits(LED2_GPIO_PORT, LED2_PIN);
break;
case STATE_LED3_OFF:
state = STATE_LED4_OFF;
GPIO_ResetBits(LED4_GPIO_PORT, LED4_PIN);
break;
case STATE_LED4_ON:
state = STATE_LED3_OFF;
GPIO_ResetBits(LED3_GPIO_PORT, LED3_PIN);
break;
case STATE_LED4_OFF:
state = STATE_IDLE;
break;
}
}
}
}
```
在本例中,有两个按键(KEY1和KEY2)和四个LED灯(LED1,LED2,LED3和LED4)。按下KEY1按键将循环切换LED1-LED4灯的状态,按下KEY2按键将反向切换LED1-LED4灯的状态。