After getting SPI connectivity going my next step porting the techfooninja nRF24L01P library to a Wilderness Labs Meadow was rewriting the SPI port initialisation, plus GetStatus and Execute methods.
I added a digital output port for the Chip Select and because I can specify the interrupt trigger edge I removed the test from the interrupt handler.
public void Initialize(IIODevice device, ISpiBus spiBus, IPin chipEnablePin, IPin chipSelectLine, IPin interruptPin)
{
_SpiBus = spiBus;
_cePin = device.CreateDigitalOutputPort(chipEnablePin, false);
_csPin = device.CreateDigitalOutputPort(chipSelectLine, false);
_irqPin = device.CreateDigitalInputPort(interruptPin, InterruptMode.EdgeFalling, resistorMode: ResistorMode.PullUp);
_irqPin.Changed += InterruptGpioPin_ValueChanged;
// Module reset time
Task.Delay(100).GetAwaiter().GetResult();
IsInitialized = true;
// Set reasonable default values
Address = Encoding.UTF8.GetBytes("NRF1");
DataRate = DataRate.DR2Mbps;
IsDynamicPayload = true;
IsAutoAcknowledge = true;
FlushReceiveBuffer();
FlushTransferBuffer();
ClearIrqMasks();
SetRetries(5, 60);
// Setup, CRC enabled, Power Up, PRX
SetReceiveMode();
}
The core of the Initialise method was moved to the Meadow application startup.
public MeadowApp()
{
try
{
var config = new Meadow.Hardware.SpiClockConfiguration(
2000,
SpiClockConfiguration.Mode.Mode0);
ISpiBus spiBus = Device.CreateSpiBus(
Device.Pins.SCK,
Device.Pins.MOSI,
Device.Pins.MISO,config);
Radio.OnDataReceived += Radio_OnDataReceived;
Radio.OnTransmitFailed += Radio_OnTransmitFailed;
Radio.OnTransmitSuccess += Radio_OnTransmitSuccess;
Radio.Initialize(Device, spiBus, Device.Pins.D09, Device.Pins.D10, Device.Pins.D11);
Radio.Address = Encoding.UTF8.GetBytes(DeviceAddress);
Radio.Channel = nRF24Channel;
Radio.PowerLevel = PowerLevel.High;
Radio.DataRate = DataRate.DR250Kbps;
Radio.IsEnabled = true;
Radio.IsAutoAcknowledge = true;
Radio.IsDyanmicAcknowledge = false;
Radio.IsDynamicPayload = true;
Console.WriteLine($"Address: {Encoding.UTF8.GetString(Radio.Address)}");
Console.WriteLine($"PA: {Radio.PowerLevel}");
Console.WriteLine($"IsAutoAcknowledge: {Radio.IsAutoAcknowledge}");
Console.WriteLine($"Channel: {Radio.Channel}");
Console.WriteLine($"DataRate: {Radio.DataRate}");
Console.WriteLine($"Power: {Radio.PowerLevel}");
Console.WriteLine($"IsDynamicAcknowledge: {Radio.IsDyanmicAcknowledge}");
Console.WriteLine($"IsDynamicPayload: {Radio.IsDynamicPayload}");
Console.WriteLine($"IsEnabled: {Radio.IsEnabled}");
Console.WriteLine($"Frequency: {Radio.Frequency}");
Console.WriteLine($"IsInitialized: {Radio.IsInitialized}");
Console.WriteLine($"IsPowered: {Radio.IsPowered}");
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
return;
}
I modified the GetStatus and ExecuteMethods to use the ExchangeData method
/// <summary>
/// Executes a command in NRF24L01+ (for details see module datasheet)
/// </summary>
/// <param name = "command">Command</param>
/// <param name = "addres">Register to write to or read from</param>
/// <param name = "data">Data to write or buffer to read to</param>
/// <returns>Response byte array. First byte is the status register</returns>
public byte[] Execute(byte command, byte addres, byte[] data)
{
CheckIsInitialized();
// This command requires module to be in power down or standby mode
if (command == Commands.W_REGISTER)
IsEnabled = false;
// Create SPI Buffers with Size of Data + 1 (For Command)
var writeBuffer = new byte[data.Length + 1];
var readBuffer = new byte[data.Length + 1];
// Add command and address to SPI buffer
writeBuffer[0] = (byte)(command | addres);
// Add data to SPI buffer
Array.Copy(data, 0, writeBuffer, 1, data.Length);
// Do SPI Read/Write
_SpiBus.ExchangeData(_csPin, ChipSelectMode.ActiveLow, writeBuffer, readBuffer);
// Enable module back if it was disabled
if (command == Commands.W_REGISTER && _enabled)
IsEnabled = true;
// Return ReadBuffer
return readBuffer;
}
/// <summary>
/// Gets module basic status information
/// </summary>
/// <returns>Status object representing the current status of the radio</returns>
public Status GetStatus()
{
CheckIsInitialized();
var readBuffer = new byte[1];
_SpiBus.ExchangeData(_csPin, ChipSelectMode.ActiveLow, new[] { Commands.NOP }, readBuffer);
return new Status(readBuffer[0]);
}
After these modifications I can send and receive messages but the PowerLevel doesn’t look right.
The program '[16720] App.exe' has exited with code 0 (0x0).
IsPowered: True
Address: Dev01
PA: 15
IsAutoAcknowledge: True
Channel: 15
DataRate: DR250Kbps
Power: 15
IsDynamicAcknowledge: False
IsDynamicPayload: True
IsEnabled: False
Frequency: 2415
IsInitialized: True
IsPowered: True
00:00:18-TX 8 byte message hello 17
Data Sent!
00:00:18-TX Succeeded!
00:00:48-TX 8 byte message hello 48
Data Sent!
Time to dig into the nRF24L01P datasheet.
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