| RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); /* I2C2 Periph clock enable */
 RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE);
 
 /* Configure I2C2 pins: SCL and SDA */
 GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_10 | GPIO_Pin_11;
 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
 GPIO_Init(GPIOB, &GPIO_InitStructure);
 
 I2C_Cmd(I2C2, ENABLE);
 
 /* Apply I2C configuration after enabling it */
 I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
 I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
 I2C_InitStructure.I2C_OwnAddress1 = 0xA0;
 I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
 I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
 I2C_InitStructure.I2C_ClockSpeed = 400000;  /* 100000也不行,PCLK1为18000000Hz */
 
 I2C_Init(I2C2, &I2C_InitStructure);
 
 这里设置断点,SR2的bit1为“1”
 
 
 |