RF control

pusink

i want to send data(byte) via RF using propelller...please help me..
thank you...

Ravenkallen

Those sort of modules are very easy to interface. I have a few similar ones i bought from sparkfun and they work moderately well...You should supply us with more information specifying the exact type of RF modules you have, That way we can help you out more....

pusink

tx and rx datasheet

Ravenkallen

Huh, those modules look a little different from the ones i usually work with...That code that you posted, Have you tried using it yet? If so what does the system act like it should? It appears to be from the code that you are trying to send data from the same circuit(Like you have the transmitter and receiver hooked up on the same propeller)... I am not sure what you are trying to accomplish, perhaps a little explanation would be in order...ALSO, on the modules i use, you have to ignore the first couple of bytes sent from the device(This is just noise that is emitted as the transmitter initializes)..

RobotWorkshop

If you can post a picture of how you have things wired or a description on how everything is connected that would help.

One thing to keep in mind is that those particular modules are just the raw RF link with NO error checking, etc. You are responsible to handle any higher level protocol that will check for valid data coming through. If you look at the documentation for the Parallax RF transceiver modules there is some example code that uses a CRC for error checking that you may be able to use in your code:

http://www.parallax.com/Store/Accessories/CommunicationRF/tabid/161/CategoryID/36/List/0/SortField/0/Level/a/ProductID/582/Default.aspx

If you use a more intelligent RF module like the XBee's or Bluetooth then they can do a lot of that for you.

Robert

Leon

You might also need to use NRZ or Manchester code.

kwinn

I took a look at the data sheets available at "http://www.laipac.com/rf-receivers.htm". Not exactly a wealth of information there but it looks like the modules use ASK modulation and have both an analog and digital demodulated signal out. The typical data rate of the digital output is 2400bps.

Looks like the hookup should be:

2400bps in >> pin6 TLP434 )))))) RLP434 pin2 >> 2400bps out

pusink

leon...

you have sample spin code for manchester code...

Leon

I don't think there is any Manchester code for the Propeller, but I could be wrong. There are simpler techniques that people have used, that work quite well.