STM32L152 DHT12 i2c读取死循环

只看该作者 · 2018-12-18 20:05

现在选用的STM32L52  去读取DHT12  通过I2C1  PB6 PB7 去读取，老是进入死循环，读取不了数据
原代码如下：

void I2C_IO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;
I2C_InitTypeDef I2C_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;

RCC_AHBPeriphClockCmd( RCC_AHBPeriph_GPIOB, ENABLE);
RCC_APB1PeriphClockCmd( RCC_APB1Periph_I2C1, ENABLE);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_I2C1);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_I2C1);
// GPIOB->AFR[0] = 0x04;
// GPIOB->AFR[0] = 0x04;

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz;
GPIO_Init( GPIOB, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

I2C_DeInit(I2C1);
I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;//I2C_Mode_SMBusHost;//I2C_Mode_I2C; //I2C¶¨Òå
I2C_InitStructure.I2C_DutyCycle =  I2C_DutyCycle_2;
I2C_InitStructure.I2C_OwnAddress1 = 0xa0; //Éè±¸×Ô¼ºµÄµØÖ· ----  ×÷Îª´ÓÉè±¸Ê±ÓÐÓÃ
I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_InitStructure.I2C_ClockSpeed = 300000;
I2C_Init(I2C1, &I2C_InitStructure);
      I2C_Cmd(I2C1,ENABLE);

I2C_AcknowledgeConfig(I2C1, ENABLE);
}

//*********  ¶ÁÈ¡Ò»¸öÊý¾Ý  ***************
void I2C1_ReadByte( uchar ReadAddr, uchar *buf, uchar len)
{
uchar i;

I2C_AcknowledgeConfig( I2C1, ENABLE); //Ê¹ÄÜÓ¦´ð  -----  ÔÀ´Ã»ÓÐ
while( I2C_GetFlagStatus( I2C1, I2C_FLAG_BUSY)); //µÈ´ýI2C²»Ã¦ wait i2c bus is not busy  µÈ´ý×ÜÏß¸´Î»

I2C_GenerateSTART( I2C1, ENABLE); //²úÉúÆðÊ¼ÐÅºÅ  send start condition  ·¢ËÍÒ»¸ö¿ªÊ¼Î»
while( !I2C_CheckEvent( I2C1, I2C_EVENT_MASTER_MODE_SELECT)) ; //EV5  test on EV5 and clear it  µÈ´ýEV5

I2C_Send7bitAddress( I2C1, ReadAddr, I2C_Direction_Transmitter); //·¢ËÍµØÖ·  send ADXL address for write ·¢ËÍÒ»¸öÎ±Ð´Ö¸Áî
while( !I2C_CheckEvent( I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)) ; //EV6  test on EV6 and clear it µÈ´ýEV6

I2C_SendData( I2C1, 0);//ReadAddr); //·¢ËÍ¶ÁµØÖ· REG_HUMIDITY_HIGH
//while( I2C_GetFlagStatus( I2C1, I2C_FLAG_BTF) == RESET) ;
while( !I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_TRANSMITTED)) ; //ÁíÍâÒ»ÖÖÐ´·¨

I2C_Send7bitAddress( I2C1, ReadAddr+1, I2C_Direction_Receiver); //send ADXL address for read ·¢ËÍÒ»¸öÎ±Ð´Ö¸Áî
while( I2C_GetFlagStatus(I2C1, I2C_FLAG_ADDR) == RESET) ;
//while( !I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED)) ; //ÁíÍâÒ»ÖÖÐ´·¨

for( i = 0 ; i < len; i++)
{
while( !I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED)) ;
*buf = I2C_ReceiveData(I2C1);
buf++;
}

I2C_AcknowledgeConfig( I2C1, DISABLE); //disable acknowledgement
I2C_GenerateSTOP( I2C1, ENABLE); //·¢ËÍÍ£Ö¹Î»
I2C_AcknowledgeConfig(I2C1, ENABLE);
}

读取程序：
void ReadEnvirTempAndHump()
{
GPIO_InitTypeDef GPIO_InitStructure;

RCC_AHBPeriphClockCmd( RCC_AHBPeriph_GPIOB, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
  GPIO_Init( GPIOB, &GPIO_InitStructure);

SET_POWER();
SET_NOINVASSENSOR();

GPIO_SetBits( GPIOB, GPIO_Pin_6);
Delay(10000);
I2C_IO_Init();
Delay(5000);

I2C1_ReadByte( DHT12_I2C_ADDRESS, SendData, 5);

｝