Tutorial for RF communication?

OK I’ve done the Xbee thing, now I want to have a go at a cheaper alternative and get RF communication going.

The requirements are to have a transmitter transmit 2 different button presses to a receiver, which will for this example turn a motor on in one direction or the other based on the button.

The transmission must go up to 10 meters ideally, and will be in almost complete line of site anyway.

Can someone provide me with a good tutorial and/or BOM of items I will need to achieve this? I have looked at the rfPIC12F675 and the accompanied receiver, but for one I cannot find them on RS or any store I can purchase from, and second, they are QTPN packages or similar, so no good for my prototying boards. And thirdly, after they stated they were easy to setup with minimal external components, I opened up the receiver datasheet and got scared by the 32 pins!!

I was hoping for a transmitter and receiver chip for each, that you setup using crystals or the likes (presumably) that operate on a certain frequency, and then I could just wire this into an ADC or comparator (PWM) of a PIC and away I go. Are my hopes going to be shattered now and am told it is far from that simple?

PS. Also, I would like to have say 5-6 of these transmitter/receiver sets in my house eventually, so would need a way to make sure they dont interfere with each other.

Use the nRF24L01+. SFE sells modules.

Leon

This the same item http://uk.rs-online.com/web/search/sear … guageId=en ?

If so, any nice tutorials on setting them up to send/receive?

That’s probably the chip.

SFE has sample code for their modules. I have a circuit and some C18 code for the PIC18F4520:

http://www.leonheller.com/MiRF%20V2/

Leon

One issue with the really cheap wireless data chips/modules (meaning much cheaper than the 802.15.4 modules) is that there’s no standard and thus all these are sole source and proprietary. If that vendor drops the product/EOL, or the vendor is acquired or goes kaput, you are hosed.

Even a student/hobbyiest cares - as you might not be able to duplicate the thing a year from now. But there are some lesser-risk vendors/chips, e.g., nRF24L01. But it’s getting long in the tooth.

The nRF24L01 and nRF24L01+ aren’t exactly “long in the tooth”. Most wireless keyboards and mice on the market use them.

Leon

I’m just looking at cost as the sole reason I was thinking of a cheaper wireless option was purely for that reason.

However, the rf24L01 is £14, and the Xbee is £19… not much in it, and the Xbee is a completely plug and play with AT architecture. Its a shame as was expecting the nordic one to be much cheaper. Do I have any alternatives, or a better source for getting the nRF24L01 cheaper than that?

The Nordic chips are very cheap in quantity.

Leon