Where is a simple program that demonstrates unidirectional data transmission over a pair of nRF24L01+ radios? It should have adequate output so that a beginner can determine that the transmission is working properly.
3 Answers
I found this site to have pretty strait forward instructions:
https://maniacbug.wordpress.com/2011/11/02/getting-started-rf24/
Main Library: https://github.com/maniacbug/RF24/
Example Sketch: https://github.com/maniacbug/RF24/blob/master/examples/pingpair/pingpair.pde
Here are several "getting started" articles that contain simple programs.
https://groups.google.com/forum/#!topic/nrf24-arduino/VaC2U5D1o_s
http://arduino-for-beginners.blogspot.com/2013/02/setup-nordic-nrf24l01-rf-modules-to.html
TMRh20 RF24 library examples work well.
Install TMRh20 RF24 library in the Arduino IDE Library Manager (“Sketch/Include Library/Manage Libraries...” and search for “RF24”). Then open the Getting Started example (“File/Examples/RF24/GettingStarted”).
You’ll need to change the “radioNumber” variable to 0
or 1
on the sending and receiving Arduino (line 13 of the code).
For the hardware I prefer to use pins 9 and 10 instead of 7 and 8 (line 16 of the code), so that all pins are connected to port B.
The nRF24 is supposed to be 5V tolerant on the data lines, but not for the power supply, so you need to connect VCC to 3.3 V. In my experience, it works best if you use it with a full 3.3 V board (ESP8266 or Arduino Pro Mini).
You absolutely need to add a strong capacitor between VCC and ground. I use a 2200 µF capacitor, but 10 µF may be enough (http://arduino-info.wikispaces.com/Nrf24L01-2.4GHz-HowTo).