技能梳理37@stm32+按键+光耦+锁存+串行转并行+继电器

技能梳理37@stm32+按键+光耦+锁存+串行转并行+继电器

1、项目简介

2、实现逻辑

3、应用场景

#主从机有线控制
#开关操作

4、核心代码梳理

//根据按下的按键执行相应的操作
void handle_key_press(int key) 
{
  char buf[20];
  sprintf(buf, "Key %d pressed", key);
	oled_print(0, 4, buf);
  CAN_TX(buf);
}

void control_relay(uint8_t position, GPIO_PinState state) {
    // 检查位置是否有效
    if (position < 1 || position > 14) {
        //printf("Invalid relay position: %d\n", position);
        return;
    }
    
    // 定义GPIO结构体
		GPIO_TypeDef* port = GPIOC;
		uint16_t pin;
    
    // 根据位置设置对应的GPIO端口和引脚
    switch (position) {
        case 1:
            port = GPIOC;
            pin = GPIO_PIN_14;
            break;
        case 2:
            port = GPIOC;
            pin = GPIO_PIN_15;
            break;
        case 3:
            port = GPIOA;
            pin = GPIO_PIN_0;
            break;
        case 4:
            port = GPIOA;
            pin = GPIO_PIN_1;
            break;
        case 5:
            port = GPIOA;
            pin = GPIO_PIN_2;
            break;
        case 6:
            port = GPIOA;
            pin = GPIO_PIN_3;
            break;
        case 7:
            port = GPIOA;
            pin = GPIO_PIN_4;
            break;
        case 8:
            port = GPIOA;
            pin = GPIO_PIN_5;
            break;
        case 9:
            port = GPIOA;
            pin = GPIO_PIN_6;
            break;
        case 10:
            port = GPIOA;
            pin = GPIO_PIN_7;
            break;
        case 11:
            port = GPIOB;
            pin = GPIO_PIN_0;
            break;
        case 12:
            port = GPIOB;
            pin = GPIO_PIN_1;
            break;
        case 13:
            port = GPIOB;
            pin = GPIO_PIN_10;
            break;
        case 14:
            port = GPIOB;
            pin = GPIO_PIN_11;
            break;    
        default:
            //printf("Invalid relay position: %d\n", position);
            return;
    }
    
    // 执行操作
    HAL_GPIO_WritePin(port, pin, state);
}

int keypad_to_num(int keypad_val) {
    // 实际按键号和按键序号之间的映射关系
    int switch_key[16] = {13, 9, 5, 1, 14, 10, 6, 2, 15, 11, 7, 3, 16, 12, 8, 4};
  
    // 查找按键号对应的序号
    for (int i = 0; i < 16; i++) {
        if (keypad_val == switch_key[i]) {
            return i+1; // 返回对应的按键号
        }
    }
  
    // 没有找到匹配的按键号，返回-1表示错误
    return -1;
}


//返回当前哪个按键被按下㿂如果没有按键被按下，则返回0
int scan_keypad(void) {
    int row, col;
    int all_unused = 1; // Assume all keys are unused

    for (col = 0; col < 4; col++) {
        /* Output a low signal to the current column */
        switch(col){
            case 0:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_RESET);
                break;
            case 1:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_11, GPIO_PIN_RESET);
                break;
            case 2:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_12, GPIO_PIN_RESET);
                break;
            case 3:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_15, GPIO_PIN_RESET);
                break;
            default:
                break;
        }

        /* Check the rows for a key press */
        for (row = 0; row < 4; row++) {
            if (!HAL_GPIO_ReadPin(GPIOB, 1 << (row + 12))) {
							HAL_Delay(100); //消抖
							if (!HAL_GPIO_ReadPin(GPIOB, 1 << (row + 12))) {
								/* Key is pressed, handle the key press */
								int key_pressed = row*4 + col + 1;
								key_pressed = keypad_to_num(key_pressed);
								if(key_pressed > 14)
									return 0;
							
								/* Check if all other keys are unused */
								for(int i = 0; i < 16; i++) {
										if(i != key_pressed - 1 && key_table[i] == 1) {
												/* Other key is already pressed, print error message and return 0 */
												//printf("Error: Another key %d is already pressed\n", i+1);
												return -1;
										}
								}

								/* Set flag to 1 if is 0 */
								if(key_table[key_pressed-1] == 0)
								{
									key_table[key_pressed-1] = 1;
									return key_pressed;
								}
								else
								{
									key_table[key_pressed-1] = 0;
									return key_pressed + 100;
								}
							}
							
            }
        }

        /* Wait a short delay before scanning the next column */
        Delay(1000);

        /* Output a high signal to the current column */
        switch(col){
            case 0:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_SET);
                break;
            case 1:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_11, GPIO_PIN_SET);
                break;
            case 2:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_12, GPIO_PIN_SET);
                break;
            case 3:
                HAL_GPIO_WritePin(GPIOA, GPIO_PIN_15, GPIO_PIN_SET);
                break;
            default:
                break;
        }
    }

    /* No key is pressed */
    return 0;
}

5、部分参考资料

6、注意事项

#使用的不是单个的按键，是矩阵键盘
#按键消抖比较简单，按的时候需要暂停1秒
#主从机程序写到一个工程文件了，通过宏定义可以进行选择
#资料中的参考硬件是之前自己的项目文件
#硬件和软件不是一一对应的，硬件更为复杂

完整可运行项目地址

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