STM32L152 i2c操作SDA和SCL始终为低 BUSY

只看该作者 · 2014-6-11 14:40

初始化代码：
GPIO_InitTypeDef  GPIO_InitStruct;
I2C_InitTypeDef I2C_InitStructure;

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB,ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2,ENABLE);

//GPIO PART
GPIO_InitStruct.GPIO_Pin    = GPIO_Pin_10 | GPIO_Pin_11;
GPIO_InitStruct.GPIO_Mode    = GPIO_Mode_AF;
GPIO_InitStruct.GPIO_OType    = GPIO_OType_OD;
GPIO_InitStruct.GPIO_Speed    = GPIO_Speed_40MHz;
GPIO_Init(GPIOB, &GPIO_InitStruct);

//I2C PART
I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
I2C_InitStructure.I2C_OwnAddress1 = I2C1_OwnAddress1;//define by myself
I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_InitStructure.I2C_ClockSpeed = I2C_SPEED_100K;

I2C_Cmd(I2C2,ENABLE);
I2C_Init(I2C2,&I2C_InitStructure);
I2C_AcknowledgeConfig(I2C1, ENABLE);

外部接一个MEMS器件，I2C线上上拉电阻10K，电平3.5V
初始化跑完GPIO_INIT之后管脚上就从高电平变成低电平了，在后面做完I2C_INIT也没回变回来，导致I2C.SR第一位始终是1，做SWRST也没用，I2C通信不上，求助啊！！！