How to capture data from a weather station

[nadabro]

Hi..

I have a wireless weather station, but it doesnt have a PC connection.. it has 3 modules:

-Wind module
-Rain module
-Display module

The communication between Wind/Rain module and the Display module is made by 434mhz..there a couple of people trying to decipher the RF codes, but it´s a long process..probably impossible.

I was thinking isn't simpler to access the data directly from the Display board and connect to PC through RS232?

Or even capture the data when it´s send to LED display?

Sorry for my ignorance:lol:

Image of the Display board
**broken link removed**

Weather station
**broken link removed**

 

[klystron]

Interface to the serial output of the base station receiver

 

[nadabro]

Interface to the serial output of the base station receiver

Thanks for the answer,

How can make the interface? Is there a pinout where to solder the wires in the board of the base station receiver to get the data?

If it helps i can get better resolution photos of the PCB..

 

[nadabro]

I´ve located the RF module in the Base station, it has 3 wires soldered to the PCB:

-DATA
-POWER
-GND

Can i connect the DATA and GND to a serial port? Will it receive the data received from the RF module?

(Data to pin 2; GND to pin 5 from the serial)

 

[betwixt]

Yes, but I don't think it will solve your problem. It seems the difficulty is decoding the data, not receiving it. If you connect to the data input to the transmitter you will get a wired version of the data sent out at 434MHz but still encoded ready for transmission. What you really need is a receiver connected to a logic analyzer, this will let you see the data as a graph and from there you can look for the pattern of bits and match them with the display to see how the protocol works.

Brian.

 

[nadabro]

Once i get the data into my computer, i will try first the many software/weather stations models that support 232..maybe i get some luck. I saw in a forum, a person trying to decode the data from a analyzer in weather station..but it´s a very long process..

Due to my null electronic knowledge, i have few questions.. in my head it was all very simple, but it will be a bit tricky..

1) I just need to solder/connect DATA/GND on the Base Station? (this one has a RF receiver, the other two modules have a RF transmiter)
2) How can i make a connection work on both sides at the same time? (to the Serial Port and to the PCB that has a LED display) Just strip down the plastic from the wire (RF-DATA-->RF PCB) and connect the wire directly from the serial port to it?
3) Do i need to connect always the GND from the serial? Can i make like 2) ?
4) Which software i use to read the DATA received from the serial port, Hyperterminal, or any 232 windows analyzer, just to confirm that i´m receiving data?


Thanks.

 

[betwixt]

You must connect two wires, ground and the data line. The voltage used on a standard computer serial port swings between +12V and -12V but your receiver (base station) probably only swings 0V to 5 or 3.3V so you need an interface circuit to change the voltage levels. If the receiver uses 5V levels I suggest you use a MAX232 device, if it uses 3.3V use a MAX3232, they are similar devices but are intended for different input voltages.
You can probably use Hyperterminal to monitor the data but it will almost certainly not be sent as text so you may see strange characters. A program that can display incoming data in hexadecimal or binary would be more suitable.

Brian.

 

[nadabro]

I have a Siemens Cable x25/x35 for mobile phones, i use this cable to connect a Fonera (Linux base wifi router) to a serial port, i suppose it´s a max232..

About the Weather Station voltage, i dont have here any multimeter, but i will try to get one. If helps, the station works on 3 batteries of 1.5v, the ac adaptor requires 6V..

 

[nadabro]

I tried my siemens cable on the station, using a 232 analyzer software i´m able to catch data every 30/40s..it´s very regular the communication, a bunch of 0000 received during 30seconds, than it receives data during 3/4seconds...the manual says the data is send every 30 seconds.

Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
Data received: 00 00 00 00 3F 3F FC 3F 3F FC 3F 3F FC 3F 3F 00 
Data received: 00 FE 3F 3F FE 3F 3F FC 3F 3F FC 3F 3F F6 3F 3F 
Data received: 00 F4 3F 3F FC 3F 3F F4 3F 3F F4 3F 3F F4 3F 3F 
Data received: 00 3F 01 00 3F 01 00 F4 3F 3F F4 3F 3F F4 3F 3F 
Data received: 00 F4 3F 3F F4 3F 00 F4 3F 3F F4 3F 3F F4 3F 3F 
Data received: 00 F4 3F 00 F4 3F 3F F4 3F 3F F4 3F 3F F4 3F 3F 
Data received: 00 F4 3F 00 F4 3F 00 F4 3F 3F F4 3F 3F F4 3F 3F 
Data received: 00 3F 03 00 F4 3F 00 F4 3F 00 F4 3F 00 F4 3F 3F
(...)
Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
(...)

This is a example of the hex data received using 2400, in 9600:

Data received: 00 00 00 00 3F 
Data received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
Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
Data received: 00 00 00 00 00 00 00 00 00 00 00 00 00 00

So it´s catching the data OK?

But i´ve encontered a problem, when i connect the cable in the station, the station doesnt receive any data from the other RF modules..looks like that i´m "stealing the data" from the RF module, and the base station is not receiving any. How can i connect it allowing to send data to my PC and to the Base Station?

Thanks for the help.

 

[betwixt]

Without seeing how it is connected and information on the module its difficult to see why the other transmitters are not getting through.
Before analyzing the data, you need to find out exactly what the Baud rate is, do not assume it is one of the standard speeds, as long as the transmitter and receiver run at the same sped, it could be anything. If you have an oscilloscope or logic analyzer, look at the width of the pulses and from that work out how many per second there would be (1/period), this will tell you the Baud rate to use.

Brian.

 

[nadabro]

Hi..

Someone on the internet decoded the RF signal...great job doing that! But from what i learned i cant receive the rf signal directly into max232..it makes sense, because i need something to process the data before it´s sent to max232.

Several people will use a arduino+RF receiver..but for me it´s just too costly and i really need an arduino just for this? Isn't there any cheaper alternatives (i´ve seen DIY boards using Atmel)? Something like **broken link removed**, or making my own board and program it?

I still have the idea of catching data through the PCB data wire, send it to the "arduino/clone/diy" and finally to the pc. Later i will had a RF receiver to the "arduino/clone/diy".

EDIT: I thik i´ll go for a arduino clone from China..and i close my case:-D

Thanks for the help.