DHT Family of Humidity and Temperature Sensors

Device driver for the DHT Family of humidity and temperature sensors. More...

Detailed Description

Device driver for the DHT Family of humidity and temperature sensors.

Files

file  dht.h
 Device driver interface for the DHT family of humidity and temperature sensors.
 

Data Structures

struct  dht_data_t
 Data type for storing DHT sensor readings. More...
 
struct  dht_t
 Device descriptor for DHT sensor devices. More...
 

Typedefs

typedef dht_t dht_params_t
 Configuration parameters for DHT devices.
 

Enumerations

enum  { DHT_OK = 0, DHT_NOCSUM = -1, DHT_NODEV = -2 }
 Possible return codes. More...
 
enum  dht_type_t { DHT11, DHT22, DHT21 = DHT22 }
 Device type of the DHT device. More...
 

Functions

int dht_init (dht_t *dev, const dht_params_t *params)
 Initialize a new DHT device. More...
 
int dht_read (const dht_t *dev, int16_t *temp, int16_t *hum)
 get a new temperature and humidity value from the device More...
 

Enumeration Type Documentation

◆ anonymous enum

anonymous enum

Possible return codes.

Enumerator
DHT_OK 

all good

DHT_NOCSUM 

checksum error

DHT_NODEV 

device type not defined

Definition at line 42 of file dht.h.

◆ dht_type_t

enum dht_type_t

Device type of the DHT device.

Enumerator
DHT11 

DHT11 device identifier.

DHT22 

DHT22 device identifier.

DHT21 

DHT21 device identifier.

Definition at line 59 of file dht.h.

Function Documentation

◆ dht_init()

int dht_init ( dht_t dev,
const dht_params_t params 
)

Initialize a new DHT device.

Parameters
[out]devdevice descriptor of a DHT device
[in]paramsconfiguration parameters
Returns
0 on success
-1 on error

◆ dht_read()

int dht_read ( const dht_t dev,
int16_t *  temp,
int16_t *  hum 
)

get a new temperature and humidity value from the device

Note
if reading fails or checksum is invalid, no new values will be written into the result values
Parameters
[in]devdevice descriptor of a DHT device
[out]temptemperature value [in °C * 10^-1]
[out]humrelative humidity value [in percent * 10^-1]
Returns
0 on success
-1 on checksum error
-2 on parsing error