DHT11 Driver

DHT11 Driver for STM32XXX Microcontrollers to retrieve data(Temperature, Humidity) from DHT11. This library also supports error handling and temperature conversion between Celcius and Fahrenheit.

Important

Specify the HAL include files in "DHT11.h"

• STM32XXXX_HAL_HEADER_FILE
• STM32XXXX_HAL_TIM_HEAEDER_FILE for your Microcontroller.

Important

Intialize a Timer to count "1us".

Reference

Types

• DHT11_StatusTypeDef

  • DHT11_OK
  • DHT11_TIMEOUT
  • DHT11_ERROR
  • DHT11_CHECKSUM_MISMATCH

• DHT11_InitTypeDef

  • Temperature
  • Humidity
  • Status

Functions

• HAL_DHT11_Init
• HAL_DHT11_DeInit
• HAL_DHT11_GetErrorMsg
• HAL_DHT11_ReadData
• HAL_DHT11_ReadTemperatureC
• HAL_DHT11_ReadTemperatureF
• HAL_DHT11_ReadHumidity

Installation

Copy the "/Inc" & "/Src" directory into your STM32 project.

Documentation

Initialization and Deinitialization

Use function HAL_DHT11_Init & HAL_DHT11_DeInit to handle Initalization and DeInitialization.

HAL_DHT11_Init

Intitalizes the DHT11 Driver.

• Arguments:

  • DHT11 instance of a DHT11 driver.
  • GPIOx where x can be (A..G) to select the GPIO peripheral for STM32xxxx family.
  • GPIO_Pin specifies the pin DHT11 is connected.
  • TIM handler for timer with frequency to count 1us.

• Returns:

  • None

HAL_DHT11_DeInit

De-initializes the DHT11 Driver.

• Arguments:

  • DHT11 instance of a DHT11 driver.

• Returns:

  • None

Reading data from the DHT11

To Read data from the DHT11, this driver provides function like HAL_DHT11_ReadData, HAL_DHT11_ReadTemperatureC, HAL_DHT11_ReadTemperatureF & HAL_DHT11_ReadHumidity

HAL_DHT11_ReadData

Reads data(Temperature, Humidity) from the DHT11 Driver.

• Arguments:

  • DHT11 instance of a DHT11 driver.

• Returns:

  • Status of the command.

HAL_DHT11_ReadTemperatureC

Reads Temperature value in Celcius from the DHT11 Driver. Status of the command is stored in DHT11_InitTypeDef->Status.

• Arguments:

  • DHT11 instance of a DHT11 driver.

• Returns:

  • Temperature in Celcius.

HAL_DHT11_ReadTemperatureF

Reads Temperature value in Fahrenheit from the DHT11 Driver. Status of the command is stored in DHT11_InitTypeDef->Status.

• Arguments:

  • DHT11 instance of a DHT11 driver.

• Returns:

  • Temperature in Fahrenheit.

HAL_DHT11_Humidity

Reads Humidity value from the DHT11 Driver. Status of the command is stored in DHT11_InitTypeDef->Status.

• Arguments:

  • DHT11 instance of a DHT11 driver.

• Returns:

  • Humidity

Error Handling

To get the messgaes related to Status of DHT11 driver have HAL_DHT11_GetErrorMsg function. After every command, DHT11 driver stores the Status code in Status instance member of the DHT11_InitTypeDef struct.

• Arguments:

  • Status status code.

• Returns:

  • Message status message.

Version

v1.0.1