Sharing my project : Wireless Room Temp Monitoring System

Hi Forum people,

So this year i started this little project of a room temperature (wireless) sensor system to monitor the temp in many locations in my place.

The idea here is to have Raspberry Pi with a RX 433Mhx Module that sniffs arround for data sent out by TX 433Mhz modules attached to an Arduino Pro Mini 5V connected to a DS18B20 module.

I just received my Arduino Pro Mini and started play around with basically programming it ... so far so good. Here is how i did it (not sure if it is even the right way) : i-build-stuff: [Wireless Room Temperature Monitoring System] Program the Arduino Pro Mini through USB Serial FT232RL Module

If you want to see the full story, please see my blog where i document everything. I already managed to test out the RX/TX 433Mhz modules using the Raspberry Pi as receiver and sender.
Check it out if you are interested :

Please let me know what you think of the whole approach or if you have any suggestion about this.

I will update you as soon as i manage to do some more !

Sounds good. It can be done. Personally, I use wireless where I can't get wires and 1-Wire (Maxim) like the DS18B20 for the others. I started with XBee Series 1 wireless (excellent support from Digi, plenty of examples) then quickly shifted to Series 2 for the total meshing capability. A lot to learn with API's and data frames, but this is the same system used in hospitals, smart metering and so on, in fact not a million miles from broadband routers. 2.4-GHz carries loads of data, but doesn't go far - 433-MHz has the range but not the data. Meshing is easier in the long run. The Digi X-CTU software is second to none. However, it took me nearly two years to get pulses from a gas meter to a display in the house. Think about it - first detect the pulses, condition and transmit the pulses, decode the data frames, add memory, logging, real time clocks and it's a whopping project. But... get it it right for one and the others are done and dusted. I love 1-Wire and all the 1-Wire IC's, plus the really long cable runs possible. Dabbled with RPi, but stuck with Arduino - Arduino has a solid industrial base in Atmel. If it's measurement, process, control, use an MCU. RPi??? Good luck - the only thing going for it is that it is an easier route to nicer displays and Internet access, does games and Scratch - then there's Digi Connect, Digi Cloud. There are loads of new SOC systems coming out almost daily. It makes my day looking at a string of 1-Wire sensors on Arduino and watching where the heat goes. Knowledge is power and one day houses will run with controls like vehicle engine management units. Now if someone could give me a hand with a DS2438??

Thanks for the suggestions tigger,

I first looked at those Xbee module, but it is way too expensive for what i am trying to do, i found those 433Mhz Chinese module for less then 5 euros for 5 pairs ...

Actually this is exactly why i chose the RPi, i am actually planning to have my temperature plotted and available on a website from anywhere. This way i will be able to have an eye on the temp in my house from anywhere in the world :slight_smile:

About DS2438, i will come back in to you in 6 month or so :stuck_out_tongue: right now i am too much of a noob to be of any value to you :slight_smile:

Me again !

Now i managed to have a RF 433 Mhz on an Arduino Pro Mini to send stuff and to sniff it : i-build-stuff: [Wireless Room Temperature Monitoring System] Sending a value through RF 433 Mhz Module from an Arduino Pro Mini 5V

Also i managed to connect a Temperature sensor DS18B20 to the Arduino Pro Mini and to measure temperature : i-build-stuff: [Wireless Room Temperature Monitoring System] Temperature sensing with DS18B20 sensor and Arduino Pro Mini

Now i need your help to combine somehow both codes into one that does 1) get the temperature from the DS18B20 store it in a variable, and then 2) send that one through the TX 433 Mhz in order to sniff it with the RX on the Raspberry Pi.

Any idea ?

Project update.

I completely changed the approach on the code to send between Arduino to Raspberry Pi. Thanks to smart people on the internet ...

The whole process described here : i-build-stuff: [Wireless Room Temperature Monitoring System] Labeling a temperature (DS18B20) from an Arduino Pro Mini to a Raspberry Pi :astonished: