Energy Monitor Shield nRF24L01+

The nRF24L01 functionality looked like a good place to start so I had a look at the documentation. The interface for connecting the nRF24L01+ module was specified as

D11 – MOSI
D12 – MISO
D13 – SCK
D8 – RF_CE

I have used the Nordic nRF240L1+ .Net Micro Framework Driver on a couple of other projects but initially struggled to get it working with this configuration. After looking at the pin outs of the nRF24L01+ and the Energy Monitor Shield schematic I think the CSN & CE are reversed.(as at March 2014).

This code works and was adapted from the sample application provided with the driver on codeplex

public class nRF240l1Module
private const byte channel = 10;
private readonly OutputPort _led = new OutputPort(Pins.ONBOARD_LED, false);
private readonly NRF24L01Plus _module;
private Timer _timer;
private byte _token;

private readonly byte[] _myAddress = Encoding.UTF8.GetBytes(“NetP1”);
//private readonly byte[] _myAddress = Encoding.UTF8.GetBytes(“NetP2”);
private readonly byte[] _otherBoard = Encoding.UTF8.GetBytes(“NetP2”);
//private readonly byte[] _otherBoard = Encoding.UTF8.GetBytes(“NetP1”);

public nRF240l1Module()
_module = new NRF24L01Plus();

public void Run()
_module.OnDataReceived += OnReceive;
_module.OnTransmitFailed += OnSendFailure;
_module.OnTransmitSuccess += OnSendSuccess;

_module.Initialize(SPI.SPI_module.SPI1, Pins.GPIO_PIN_D8, Pins.GPIO_PIN_D7, Pins.GPIO_PIN_D2);
_module.Configure(_myAddress, channel, NRFDataRate.DR250kbps);

_timer = new Timer(SendMessage, null, new TimeSpan(0, 0, 0, 1), new TimeSpan(0, 0, 0, 1));

private void OnSendSuccess()

private void OnSendFailure()
Debug.Print(“Send failed!”);

private void OnReceive(byte[] data)
Debug.Print(“Token <- ” + data[0]);

private void SendMessage(object state)
_module.SendTo(_otherBoard, new[] { _token });
Debug.Print(“Token -> ” + _token);


Energy Shield with nRF24L01Plus

Energy Shield with nRF24L01Plus

One thought on “Energy Monitor Shield nRF24L01+

  1. Pingback: Azure Event Hub Service Gateway V0.1 | devMobile's blog

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