Topic: Wireless Protocol Reverse Engineered

[burko007]

Hi all,

I have just spent the last few days reverse engineering the wireless protocol from a Jaycar XC0348 wireless weather station (made by Fine Offset i believe). While there is plenty of information out there on the USB/Serial protocol i could not find anyone who has determined the wireless protocol for this type of weather station (there has been some work on the Oregon Scientific stations). At this stage i have a basic 433Mhz receiver module connected to a microcontroller and i can decode temperature, humidity, wind speed, direction, and have identified the rainfall byte but still making sense of its value.

What i am wondering is if this is of interest to this community? What i essentially aim to do is have a simple dongle that can plug into a computer and log the weather station information directly from the transmitter without having to be connected to the base station. Or even have something that plugs into a router so you can access the weather information from a laptop/ipad etc. Once my software is a little more mature i intend on open sourcing it for all to access and may build a small number of dongles if anyone is interested?

Cheers,

Leon

[Stetson1]

I'd certainly be interested in a dongle that bypasses the console. Looks like that model is similar to the WH-1080 and clones.

Todd

[burko007]

What do you think would be a preferred option:

1. A USB dongle for the computer (downside of this is the computer has to be on any time you want to view the data)

2. A Ethernet based device that would plug into a home router. The idea of this being you can access the information from any other computer device in the house (iPad, smartphone etc). (This would be a more expensive option than the first)

Or another option possibly?

[Stetson1]

Interesting options. I would think either is good, for me my PC is on all the time updating my website and other services so the dongle is best. That said, the device that could be accessed from any PC had some possibilities.

Todd

[davew]

Leon,

very interested! How are you progressing?

I've been working on the same for several weeks (on and off). Using an Arduino and code from Practical Arduino "Weather Station Receiver".

From what I've discovered the rainfall is 'number of bucket tips' which are 0.3 mm of rainfall, but not sure over what period that accumulates.

Dave

[Charlie]

The rain counter counts bucket tips until either the remote unit battery is removed, or the counter rolls over. Each tip is ~0.3 mm.

Just curious - since you are planning to "open source" this information, could you post what you've recovered as the bit stream so far?
My unit runs at 915 MHz, so receivers are a bit harder to find, but I likely can help with the decoding.

[burko007]

There didn't seem to be a great deal of interest so I have put this project on the backburner. I can send you my decoding source code if you like but it is not polished enough yet for public release. (I have passed my source code onto other members who have sent private messages)

I found a cheap embedded Ethernet board I intend on using to host the weather data so that a PC does not have to be on to serve the data. Was actually working on it this evening. Will post my progress as I go.

[Stetson1]

Still interested in your findings, also the remote Ethernet board so I don't need to run my PC continuously, although the webcam requires it so it may be a moot point.

Todd

[DerekK19]

Hi Leon

I'm interested in your library, no matter how unpolished it is. I've seen lots of cheap deals on WS1093 and WS 2083 weather stations and cracking the protocol would mean I can link one up to an Arduino and then to Ethernet. I've already got the Arduino, RF receiver and Ethernet working, plus a Windows web service that records data to a SQL server. I have written an iPhone app that can get the SQL data from the web service and display today's temperature graph. At the moment I'm getting my temp readings from a second Arduino with a temperature sensor, but getting the extra infor from a weather station would be great.

Cheers
Derek at GordonKnight dot co dot uk

[burko007]

I have received a bit more interest from PMs. Attached is the code i was using to decode the weather data. (Note that this is just the software module to decode the weather station data and not register setup etc on the microcontroller). This was written for a Microchip dsPIC and compiled using MPLAB C30 compiler. Note the device ID that the station transmits is randomly generated when reset is pressed on the transmitter, you will have to adjust the code to suit your station. I have not sorted out the CRC yet.

If you make some more progress, please post your results.

Cheers,

Leon

[MrFollies]

I'm keen to pick this up.

But the included source files are missing some header files (main.h, UART.h and system.h).
Are there more files available?

[aweatherguy]

have your written anything down about the RF message format?

would be interested in that...