STM32 Peripheral driver--dht11 temperature and humidity sensor

has been tested on the STM32. This example uses the PC0 pin to connect the DHT11 data pins.

The Dth11_test function in the following code is invoked in the main function.

Data definition:     //----The following variables are global variables--------    //----temperature is high 8 bit = = u8t_data_h------    //----temperature low 8 bit = = u8t_data_l------    //----Humidity High 8-bit = = u8rh_data_h-----    //---- Humidity low 8 bit = = u8rh_data_l-----    //----Check 8-bit = = U8checkdata-----u8  u8t_data_h,u8t_data_l,u8rh_data_h
, U8rh_data_l,u8checkdata;

u8  u8t_data_h_temp,u8t_data_l_temp,u8rh_data_h_temp,u8rh_data_l_temp,u8checkdata_temp; #define BOOL unsigned char #ifndef true #define TRUE 1 #endif #ifndef false #define FALSE 0 #endif static void Dht11_da Tapin_configure_output (void) {     GPIO_InitTypeDef  gpio_initstructure;   
      //rcc_apb2periphclockcmd (Rcc_apb2periph_afio, DISABLE);     rcc_apb2periphclockcmd (RCC_APB2PERIPH_GPIOC, enable);    //enable PC Port clock                       gpio_initstrucTure. Gpio_pin = gpio_pin_0;                //pc.0 port configuration  & nbsp;   gpio_initstructure.gpio_mode = gpio_mode_out_pp;         //push-pull output      gpio_initstructure.gpio_speed = Gpio_speed_
50MHz;
     gpio_init (GPIOC, &gpio_initstructure); } static void Dht11_datapin_configure_input (void) {       GPIO_InitTypeDef  datapin;& nbsp;              datapin.gpio_pin = gpio_pin_0;                       datapin.gpio_mode = Gpio_mode_in_ floating;         //Hanging           datapin.gpio_speed = Gpio_
Speed_50mhz;
    gpio_init (GPIOC, &datapin); BOOL dht11_get_databit (void) {    uint8_t val;           val = Gpio_readinputdatabit (GPIOC, gpio_pin_0);     if (val = = bit_reset) {        return FALSE;     }else{&
nbsp;       return TRUE;    &nbsp} void Dht11_set_databit (BOOL level) {    if (level = = TRUE) {    &nbs
p;   gpio_setbits (GPIOC, gpio_pin_0);     }else{        gpio_resetbits (GPIOC, gpio_pin_0);    &NBSP}} void Mdelay (u16 ms)   {    if (MS!= 0) {        delay_ms (ms)
;    &nbsp} void Udelay (u16 us)   {    if (US!= 0) {       &nbsp
;d Elay_us (US);    &nbsp} static uint8_t dht11_read_byte (void) {          uint8_t i; &nbs
P     uint8_t data = 0;            &NBsp;                    for (i = 0; i < 8; i+ +)             {             data & lt;<= 1;                    while (!
Dht11_get_databit ()));
        udelay (10);
        udelay (10);

        udelay (10);         if (Dht11_get_databit ())     {      
     data |= 0x1;
            while (Dht11_get_databit ());         } else{                & 

nbsp;}     }                               return data; }   static uint8_t dht11_start_sampling (void) {    dht11_datapin_configure_output ();   
  //Host pull down 18ms        dht11_set_databit (FALSE);
    mdelay (18);
    dht11_set_databit (TRUE);
    //Bus-pull high host delay 20US     Udelay (10);
    udelay (10);
    udelay (10);
    udelay (10);

    //host set to input to judge the response signal     dht11_set_databit (TRUE);

    dht11_datapin_configure_input ();     //Determine if there is a low level response signal from the machine if not responding to jump out, the response is running down            if (! Dht11_get_databit ())         //t!           { & nbsp  //Determine whether the 80US low level response signal from the machine is terminated             while (!
Dht11_get_databit ()));     //printf ("DHT11 answers.\r\n");
    //judge whether the 80us high level is emitted from the machine, such as incoming data receiving status        while (Dht11_get_databit ());
       return 1;    &nbsp     return 0;               } void Dht11_get_data (void) {          U8 temp;     if (dht11_st Art_sampling ()) {       //printf ("DHT11 is ready to transmit data\r\n");         //Data Reception status               
   u8rh_data_h_temp = Dht11_read_byte ();
        u8rh_data_l_temp = Dht11_read_byte ();
        u8t_data_h_temp     = dht11_read_byte ();
        u8t_data_l_temp     = dht11_read_byte ();        u8checkdata_temp = Dht11_read_byte ();        /* Data transmission finishes, pull the bus is high * *     & nbsp;   dht11_datapin_configure_output ();            dht11_
Set_databit (TRUE);        //data validation         temp= (u8t_data_h_
TEMP+U8T_DATA_L_TEMP+U8RH_DATA_H_TEMP+U8RH_DATA_L_TEMP);         if (temp==u8checkdata_temp)         { 
           u8rh_data_h=u8rh_data_h_temp;
            u8rh_data_l=u8rh_data_l_temp;
            u8t_data_h=u8t_data_h_temp;
            u8t_data_l=u8t_data_l_temp;             u8checkdata=u8checkdata_temp;             printf ("DHT11 tempature%d.%d  humidity%d. %d \ r \ n ",                 u8t_data_h,                  u8t_data_l,                  U8rh_data_h,    

             u8t_data_l);       }else{            printf ("checksum
Failure \ r \ n ");       }     }else{        printf ("DHT11 Didn ' t answer. Sampling failed.
\ r \ n ");    &nbsp} void Dth11_test () {    while (1)    &nbsp {        dht11_get_data ();         delay_ms (1000);




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