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davewanna
- 16th May 2008, 03:59
Hi all..

I have had an idea for a while to convert one of my projects to have a wireless display/controller.. In a recent order, I grabbed a couple of RFM12B RF modules found at http://www.futurlec.com/Radio.shtml (down the bottom)..

Now that I have them, I've started reading up about them, and haven't been able to find a lot of information on where to start. The included programming guide has an example of use written in C.. But I don't know C. I have been doing a lot of research of all kinds of RF devices, but haven't been able to work out exactly how much of it all is relevant to this particular device.

I have a basic understanding of simple uni-directional RF transmission, but I feel I may have gone in over my head getting this device for my first attempt.


Has anyone here used these modules? Or does anyone know where I can find some working (picbasic) code that uses them, or can be used for them? I'm even struggling to grasp the idea of how many registers to I have to set, which pins of the module do what. (Does it send and receive data on the same pin? etc) I have to do some more reading up on FSK as I don't understand at this stage.

I have several 16F877A'a around that I will be using, also the project I want to fit this to is using a 16F877A. The datasheet and programming guide for the module is also on the link above.



I guess my question is can someone point me in the right direction, or should I have bought something simpler?

Regards,

Dave

mackrackit
- 16th May 2008, 12:56
I am pretty sure the modules you have are like the TWS/RWS ones here.
http://www.rentron.com/remote_control/remote1.htm

Once they are hooked up you will just use one of the serial commands in PIC BASIC to send data.

Go from PIC to PIC with wires first. Then replace the wires with RF.

davewanna
- 16th May 2008, 14:36
I have read up about that Ruf-bot project amongst other things.. However where the modules I have are different to others I have read about, is that they are a transceiver. Can transmit and receive with the one module. They also had the TWS/RWS modules, however I wanted 2-way data, so for the price of 2 transmit, and 2 receive modules, I could get just 2 transceivers and save my pennies.

If I ditch this idea, and go for 2 transmitter, and 2 receivers, can one of each be connected to each 16f877 in order to give me bi-direction data? If so how does that work? both connected to the same serial pin, and either module 'selected' as it is needed?

I've hit a wall with the datasheet, it's got many many pages of registers that it looks like I need to set before I even think about sending data.

Regards,

Dave

mackrackit
- 16th May 2008, 14:54
OOPS,I was looking at the wrong part. Have not used them, but looks like data is shifted into them like a shift register and data out is by serial?

If you use a separate transmitter and receiver you would use two pins on the PIC, one for TX and one for RX. (you could use one pin if serial is software) When sending or receiving you will need to turn the opposite module off.