++ed by:
SREZIC CREDO BINJOY

3 PAUSE users
1 non-PAUSE user.

Author image Gligan Calin Horea
and 1 contributors

NAME

RPi::PIGPIO::Device::DHT22 - Read temperature and humidity from a DHT22 sensor

DESCRIPTION

Uses the pigpiod to read temperature and humidity from a local or remote DHT22 sensor

SYNOPSIS

    use RPi::PIGPIO;
    use RPi::PIGPIO::Device::DHT22;

    my $pi = RPi::PIGPIO->connect('192.168.1.10');

    my $dht22 = RPi::PIGPIO::Device::DHT22->new($pi,4);

    $dht22->trigger(); #trigger a read

    print "Temperature : ".$dht22->temperature."\n";
    print "Humidity : ".$dht22->humidity."\n";

METHODS

new

Create a new object

Usage:

    my $dht22 = RPi::PIGPIO::Device::DHT22->new($pi,$gpio);

Arguments:

  • $pi - an instance of RPi::PIGPIO

  • $gpio - GPIO number to which the sensor is connected

temperature

Return the last read temperature

humidity

Return the last read humidity

last_read

When was the last read done (unix timestamp)

trigger

Trigger a new read from the sensor.

Note: The read is not imediate, it's done asyncronyous. After calling trigger you shoud sleep for a second and than you should get the values received by calling temperature() and humidity() .

You should always chek the timestamp of the last read to make sure we were actually able to read the data after you called trigger()

DHT22 can freeze if you call trigger too often. Don't call it more than every 3 seconds and you should be fine

PRIVATE METHODS

receive_data

Callback method used to read and put together the data received from the sensor

reset_readings

Reset internal counters that help us put together data received from the sensor