DHT22 with 1-wire protocol

Projects Networking, Protocols, and Devices
1

Is it possible to use some digital sensors like DHT22 on 1-wire bus?
Maybe with some adapters or so?

I working on smart home architecture and would like to use some Arduino sensors in it.

2

vichaz:
Is it possible to use some digital sensors like DHT22 on 1-wire bus?

No

vichaz:
Maybe with some adapters or so?

It will be difficult because DHT22 use a private protocol.
Recognition of "0" or "1" bit is based on to distinguish the "1" lengh. --> see attached pic.
For more information see DHT22 datasheet or have a look inside the DHT22 arduino library.

vichaz:
I working on smart home architecture and would like to use some Arduino sensors in it.

They are no "Arduino sensors" they are only "sensors".
You can use sensors with any micro-controller : so for sensor read the datasheet is very important.

forum_dht22.jpeg

3

What about to use [DHT22 together with Atmega328 (or other) in order to read data from sensor] AS SLAVE.
SLAVE will convert data to other format (maybe JSON) and send it somehow (I dont know if this is possible) to master via 1-wire bus?

4

Sorry, I don't understand, I am not english.

5

I'm too (Ukraine)
but translate.google.com?

6

on the 1-wire bus every device has an address. The DHT22 doesn't has such address although the protocol to fetch data from it has similarities with 1-wire.

If you want to use the DHT22, please try my library - Arduino Playground - DHTLib -

7

I want to use 1-wire protocol for my smart home system
But as I understand it means that I have to use only Dallas Semiconductor's sensors which supports 1-wire protocol

So, I would like to clarify if I can use any other sensors which return digital signal (for example DHT22)

I know that DHT22 not compatible with 1-wire protocol but I thought about some "adapter" between digital sensor and 1-wire protocol.

MY THEORETICAL IDEA:
I want to use DS2408 or DS2413 as SLAVE on 1-wire bus which support this protocol. DS2408 should get data from DHT22 and send it to 1-wire MASTER (DS9490R - http://sigma.octopart.com/17606294/image/Maxim-Integrated-DS9490R.jpg). So, I would like to clarify if this is possible or not.

DS2408 has address of 1-wire protocol, so we can ask data of this SLAVE. But how to implement data transfer from DHT22 to DS2408 and then to DS9490R and in which format I don't know for the moment.

DHT22 can be connected to some Arduino controller (for example Atmega328) which have library to work with this (and any other Arduino compatible) digital senson. Then Atmega328 can convert received data from DHT22 to some other format (for example JSON) which will be understandable by 1-wire slave controller (DS2408).

I know that this is very complicated and probably not optimal price solution but I don't want to be limited only by sensors proposed by Dallas Semiconductor Corp.

8

There is a thread about a 1 wire slave here on the forum and you should combine that with a DHT22 library on an Arduino UNO or a selfmade board.

Perfectly possible, I would set it up this way.

void loop()
{
  if (time_for_new_measurement)
  {
    temp = DHT22.getTemperature();
    hum = DHT22.getTemperature();
  }

  if (oneWireSlave.requestPending)
  {
    send(temp);
    send hum);
  }
}
9

Thank you, I will look to it