DHT11

Connects over

GPIO pins

Made by

Aosong

Datasheet

mouser.com

Use it

hardware {
    device dht: DHT11(pin: 16)
}

every 1s {
    let value: float = dht.humidity()
    log("dht", "humidity={value}")
}

The DHT11 is wired to ordinary GPIOs: give each of its pins (pin) as a named argument. The compiler checks every pin can do its job.

Methods

• dht.humidity() -> float

  Humidity %

• dht.temperature() -> float

  Temperature in °C

Wiring

Specifications

Current

0.3 mA measuring, 60 μA standby

Humidity

20 – 80% RH ±5%

Sample rate

Once per second (max)

Temp

0°C to +50°C ±2°C

Voltage

3.3V – 5.5V

Tips

• DHT11 is the cheap variant — wide tolerance, integer resolution.
• Single-wire protocol is timing-critical; can be unreliable on FreeRTOS without disabling interrupts during read.
• If you need accuracy, use DHT22 instead.

Alternatives worth knowing:

• DHT22: Same sensor family, ±0.5°C / ±2% RH — usually worth the small price difference.
• AHT20: I²C, smaller, more accurate, cheaper — recommended for new designs.