DHT11.zip_DHT11_DHT11温湿度stm32_STM32 DHT11_dht11 stm32

/** ****************************************************************************** * @file DHT11.c * @author Eshen Wang * @version V1.0.0 * @date 1-May-2015 * @brief DHT11 temperature and humidity sensor driver. ****************************************************************************** * @attention * * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDATAG CUSTOMERS * WITH CODATAG INFORMATION REGARDATAG THEIR PRODUCTS IN ORDER FOR THEM TO SAVE * TIME. AS A RESULT, MXCHIP Inc. SHALL NOT BE HELD LIABLE FOR ANY * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE * CODATAG INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS. * * <h2><center>&copy; COPYRIGHT 2014 MXCHIP Inc.</center></h2> ****************************************************************************** */ #include "mico.h" #include "DHT11.h" /*------------------------------ delay function ------------------------------*/ void Delay_us(uint32_t nus) { MicoNanosendDelay( 1000*nus ); } void Delay_ms(uint16_t nms) { mico_thread_msleep(nms); } /*--------------------------------- DHT11 Operations -------------------------*/ //Reset DHT11 void DHT11_Rst(void) { DHT11_IO_OUT(); //SET OUTPUT DHT11_DATA_Clr(); //GPIOA.0=0 Delay_ms(25); //Pull down Least 18ms DHT11_DATA_Set(); //GPIOA.0=1 Delay_us(30); //Pull up 20~40us } /*return 1错误，0正确*/ uint8_t DHT11_Check(void) { uint8_t retry=0; DHT11_IO_IN(); //SET INPUT while (DHT11_DQ_IN&&retry<100) //DHT11 Pull down 40~80us { retry++; Delay_us(1); } if(retry>=100) return 1; else retry=0; while (!DHT11_DQ_IN&&retry<100) //DHT11 Pull up 40~80us { retry++; Delay_us(1); } if(retry>=100) return 1; //chack error return 0; } uint8_t DHT11_Read_Bit(void) { uint8_t retry=0; while(DHT11_DQ_IN&&retry<100) //wait become Low level { retry++; Delay_us(1); } retry=0; while(!DHT11_DQ_IN&&retry<100) //wait become High level { retry++; Delay_us(1); } Delay_us(40);//wait 40us if(DHT11_DQ_IN) return 1; else return 0; } uint8_t DHT11_Read_Byte(void) { uint8_t i,dat; dat=0; for (i=0;i<8;i++) { dat<<=1; dat|=DHT11_Read_Bit(); } return dat; } /*return 0正确，-1传感器检测错误，1数据错误*/ uint8_t DHT11_Read_Data(uint8_t *temperature,uint8_t *humidity) { uint8_t buf[5]; uint8_t i; DHT11_Rst(); if(DHT11_Check()==0) { for(i=0;i<5;i++) { buf[i]=DHT11_Read_Byte(); } if((buf[0]+buf[1]+buf[2]+buf[3])==buf[4]) { *humidity=buf[0]; *temperature=buf[2]; return 0; } } else { return -1; } return 1; } uint8_t DHT11_Init(void) { DHT11_IO_OUT(); DHT11_Rst(); return DHT11_Check(); }