Recently I got access to 37 In 1 Sensor Modules 37in1 Kit For Arduino Uno R3 Mega 2560 - Sensors - AliExpress
And I am trying to sort out how to wire DHT11 of it for a purpose of measuring humidity and temperature.
Could you advise to what three pins of the Xavier pins the sensor needs to be connected with its vcc, data and gnd pins, please?
External Media
image source
For ground wiring, it seems taht one of the pins listed below can be used:
6,9,14,20,25,30,34,39
If the data is ON/OFF only, it is GPIO.
In the case of an analog sensor, it reads in SPI using A/D Converter (MCP3008).
From the data sheet:
https://www.mouser.com/ds/2/758/DHT11-Technical-Data-Sheet-Translated-Version-1143054.pdf
The DHT-11 uses a custom digital timing data protocol on its data pin.
You will need to hook it up to a GPIO pin – any GPIO pin that can serve as input and interrupt source will work. I’d probably use pin 13. Remember to look up the actual GPIOxxx pin number for the pin you choose.
The DHT-11 should use 5V power so hook it to 5V and GND.
You will have to write code that generates interrupts on pin changes, and decode the signal by measuring the timing of those interrupts.
You also need a pull-up resistor from the data pin to the 3.3V pin because the output is open-collector. (Note: Don’t hook to 5V pin, because doing so will overvolt the GPIO inputs on the Xavier!)
Adafruit has some good general information about the DHT-11: Overview | DHT11, DHT22 and AM2302 Sensors | Adafruit Learning System
Note that you have to be able to translate the requirements of the sensor, into actual C++ or Python code on the Xavier; there is no code you can copy-and-paste to do exactly what you want, that I know of.
You can, for example, read the source code of the AdaFruit DHT-11 Arduino or Python library to learn how the sensor and code to interact with it works, and re-create the same on the Xavier.
GitHub - adafruit/Adafruit_Python_DHT: Python library to read the DHT series of humidity and temperature sensors on a Raspberry Pi or Beaglebone Black.
@snarky,
Do you mean that the data pin will need to be bot connected to 3.3V and pin 13? like in parallel and to 3.3v via the pull up resistor?
Yes, the datasheet for that sensor says the input needs a pull-up. Thus, you wire the sensor pin to the GPIO input pin, and also through a pull-up resistor to the 3.3V rail.
Thank you for your response.
It seems that my implementation of dht11 has a 10k resistor already onboard as it is more like the left depicted at thew attached image
source
External Media
I am connecting VCC to pin 1
Signal/Data to pin 13
and ground to pin 9
Now it flashed red LED
Next question that I will try to address is how to read from pin 13
There is some code at
But how to read with it from pin13?
Attempt 1:
git clone https://github.com/torvalds/linux/
More reference:
would anybody be able to add on how to read from attached sensor using the loaded kernel driver/module somehow?
is it likely that the module loaded adds a device to /dev/ ?
attached file is dht11.ko a pluggeable module renamed to txt format that can be loaded with reverse fileformat txt->ko conversion and further modprobe
Does the following location seem as correct for locating outputs of the device?
cat /sys/bus/iio/devices/iio\:deviceX
Is the jetson-gpio the way to go?
dht11.txt (309 KB)