HAL_GPIO_WritePin(GPIOB,GPIO_PIN_3,1);HAL_GPIO_WritePin(GPIOB,GPIO_PIN_0,0);if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_4)==0){HAL_Delay(20);KeyValue=0;while(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_4)==0);HAL_Delay(20);}else if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_5)==0){HAL_Delay(20);KeyValue=1;while(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_5)==0);HAL_Delay(20);}else if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_6)==0){HAL_Delay(20);KeyValue=2;while(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_6)==0);HAL_Delay(20);}else if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_7)==0){HAL_Delay(20);KeyValue=3;while(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_7)==0);HAL_Delay(20);}这是扫描第()行
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