我们一般见的结构体初始化有两种： ~~~ typedef struct { uint32_t I2C_ClockSpeed; /*!< Specifies the clock frequency. This parameter must be set to a value lower than 400kHz */ uint16_t I2C_Mode; /*!< Specifies the I2C mode. This parameter can be a value of @ref I2C_mode */ uint16_t I2C_DutyCycle; /*!< Specifies the I2C fast mode duty cycle. This parameter can be a value of @ref I2C_duty_cycle_in_fast_mode */ uint16_t I2C_OwnAddress1; /*!< Specifies the first device own address. This parameter can be a 7-bit or 10-bit address. */ uint16_t I2C_Ack; /*!< Enables or disables the acknowledgement. This parameter can be a value of @ref I2C_acknowledgement */ uint16_t I2C_AcknowledgedAddress; /*!< Specifies if 7-bit or 10-bit address is acknowledged. This parameter can be a value of @ref I2C_acknowledged_address */ }I2C_InitTypeDef; ~~~ 比如这个结构体，我们一般这样初始化： ~~~ I2C_InitTypeDef i2c; i2c.I2C_Ack = I2C_Ack_Enable; i2c.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; i2c.I2C_ClockSpeed = clock*1000; i2c.I2C_DutyCycle = I2C_DutyCycle_2; i2c.I2C_Mode = I2C_Mode_I2C; i2c.I2C_OwnAddress1 = addr; ~~~ ~~~ I2C_InitTypeDef i2c = { I2C_Ack_Enable, I2C_AcknowledgedAddress_7bit, clock*1000, I2C_DutyCycle_2, I2C_Mode_I2C, addr}; ~~~ 希望大家不要纠结我这个结构体变量的顺序，肯定错了，我只是说下有这种方法！ 但是在linux内核里面有这样一种初始化方法： ~~~ I2C_InitTypeDef i2c = { .I2C_Ack = I2C_Ack_Enable , .I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit, .I2C_ClockSpeed = 40000, .I2C_DutyCycle = I2C_DutyCycle_2, .I2C_Mode = I2C_Mode_I2C , .I2C_OwnAddress1 = 0x0a }; ~~~ 但是在keil里面默认是不可以用这种方法初始化的，他属于C99的标准，但是keil默认是C90的标准！ 如果需要这样用的话，或者你拿到的工程代码里面有这样定义的，我们可以这样设置就可以了！  蓝桥杯-嵌入式交流群 147520657