No connection between two RFM12B

Added by firlefranz about 4 years ago


some time ago I bought this nice six pack of RFM12B modules (433MHz) from the JeeLabs Shop. I’d like to use two of the modules for a Arduino based thermometer. The outside sensor uses the TinyTX PCB from Nathan Chandrell including a Attiny84 and a DS18B20 temperature sensor. At the receiver side I’m using a Atmega328 and the common connection to the RFM12B as specified in this picture:

The antennas are 165mm long silver wire.

I could burn the bootloader on the Attiny using the Arduino Uno without a problem and also the upload of the code works fine as specified on the TinyTX page. For the first test I’m using the DS18B20 test sketch from the TinyTX page (\_DS18B20/TinyTX\_DS18B20.ino). Since it’
s been an old script and the TinyTX has become popular I’m not expecting any error here. On the receiver side I’m using a simple receiving example from the same website (\_RX\_Simple/TinyTX\_RX\_Simple.ino). But the problem is that I don’
t get any temperature values submitted.
The first thing I tested was the DS18B20 but it works they way it should. Also the power for the TinyTX board is stable at 3.3V. The receiver shows in the console just the Serial.println commads specified in the setup() part of the program, but it’s not receiving any data.

At the transmitter side I used another TinyTX board with another RFM12B (since I bought 6 of them), but nothing worked. I really need some help.


Replies (79)

RE: No connection between two RFM12B - Added by JohnO almost 4 years ago

I’ll have a go if you like.

RE: No connection between two RFM12B - Added by JohnO almost 4 years ago

I think you are up and running now Cornelius, perhaps you will post a video of your great project going through its paces.

RE: No connection between two RFM12B - Added by firlefranz almost 4 years ago

I’ll do so, as soon as I’ve finished another PCB. Some parts are missing at the moment and for a better description I need a front plate in English language. My own thermometer is in German of course.

But as a short preview I can show at least one picture. As you can see there is a matrix of letters which show up the temperature like the Qlocktwo by B&F. It’s written “It is twenty one degrees celsius”. This is just my prototype with a cable connected DS18B20 going through the window frame to the outside. Within the new design of the PCB a RFM12B can be connected to get a wireless connection to a outside temperature sensor. If somebody is interested in the PCB, I have some of them in stock and can also provide CNC machined housings and front plates.

RE: No connection between two RFM12B - Added by martynj almost 4 years ago


Very attractive - worth the effort indeed !