语法格式：表达式？ 值1：值2如果表达式结果为真，则为值1，否则为值2.#define Read_IIC1_SDA() ((GPIOB->IDR&GPIO_Pin_9)!=0)?1:0就是说((GPIOB->IDR&GPIO_Pin_9)!=0)为真，则Read_IIC1_SDA() = 1 否则Read_IIC1_SDA()=0
