DHT22 temperature sensor library that uses the standard Linux kernel GPIO interface.
It is a header only library so all you need to do is include the dht22.c file in your project.
To use it you first need to initialize the gpiod structures.
#include <gpiod.h>
int main(){
struct gpiod_chip *chip;
struct gpiod_line *line;
/* Use gpiodetect to get your GPIO chip dev file */
chip = gpiod_chip_open("/dev/gpiochip0");
if (!chip){
printf("Error opening chip\n");
return -1;
}
/* The second parameter is the GPIO pin number */
line = gpiod_chip_get_line(chip, 4);
if (!line) {
gpiod_chip_close(chip);
return -1;
}
}As the sensor is very simple, it only contains a single function. Usage example:
/* Continuously get the temperature and humidity */
float temp;
float hum;
while(1){
/* All you need to read the sensor */
DHT22_RC rc = dht22_read(line, &temp, &hum);
if(rc != DHT22_SUCCESS){
printf("RC: %d\n", rc);
}
printf("Temp: %f Humi: %f\n", temp, hum);
sleep(3);
}