This tutorial by user Alex Samorukov shows us how to get the DHT-11 temperature sensor readings configured on a Raspberry Pi running FreeBSD. Follow the link provided below for the full set of instructions.


Connecting sensor to the RPi

DHT-11 is a very cheap temperature/humidity sensor which is commonly used in the IoT devices. It is not very accurate, so for the accurate measurement i would recommend to use DHT21 instead. Anyway, i had DHT-11 in my tool box, so decided to start with it. DHT-11 using very simple 1 wire protocol – host is turning on chip by sending 18ms low signal to the data output and then reading 40 bytes of data. Details about the protocol could be found in the specification. To read data from the chip it should be connected to the power (5v) and gpio pin. I used pin 2 as VCC, 6 as GND and 11 as GPIO (it is GPIO17, see pinout):

Full tutorial:

Reading DHT11 temperature sensor on Raspberry Pi under FreeBSD