RFM9X.IoTCore Adafruit LoRa Radio Bonnet support

The RFM9X chip select line on the Adafruit LoRa Radio Bonnet 868 or 915MHz with OLED RFM95W is connected to pin 26(CS1), the reset line to pin 22(GPIO25) and the interrupt line to pin 15(GPIO22).

When I ran the RFM9XLoRaDeviceClient from my RFM9X.IoTCore library with the following configuration

#if ADAFRUIT_RADIO_BONNET
	private const byte ResetLine = 25;
	private const byte InterruptLine = 22;
	private Rfm9XDevice rfm9XDevice = new Rfm9XDevice(ChipSelectPin.CS1, ResetLine, InterruptLine);
#endif

public void Run(IBackgroundTaskInstance taskInstance)
{
	rfm9XDevice.Initialise(Frequency, paBoost: true, rxPayloadCrcOn : true);
#if DEBUG
	rfm9XDevice.RegisterDump();
#endif
	rfm9XDevice.OnReceive += Rfm9XDevice_OnReceive;
#if ADDRESSED_MESSAGES_PAYLOAD
	rfm9XDevice.Receive(UTF8Encoding.UTF8.GetBytes(Environment.MachineName));
#else
	rfm9XDevice.Receive();
#endif
	rfm9XDevice.OnTransmit += Rfm9XDevice_OnTransmit;

	Task.Delay(10000).Wait();

	while (true)
	{
		string messageText = string.Format("Hello from {0} ! {1}", Environment.MachineName, MessageCount);
		MessageCount -= 1;

		byte[] messageBytes = UTF8Encoding.UTF8.GetBytes(messageText);
		Debug.WriteLine("{0:HH:mm:ss}-TX {1} byte message {2}", DateTime.Now, messageBytes.Length, messageText);
#if ADDRESSED_MESSAGES_PAYLOAD
		this.rfm9XDevice.Send(UTF8Encoding.UTF8.GetBytes("AddressHere"), messageBytes);
#else
		this.rfm9XDevice.Send(messageBytes);
#endif
		Task.Delay(10000).Wait();
	}
}
#endif

I could see messages being sent and received in the debug output

Register 0x3e - Value 0X00 - Bits 00000000
Register 0x3f - Value 0X00 - Bits 00000000
Register 0x40 - Value 0X00 - Bits 00000000
Register 0x41 - Value 0X00 - Bits 00000000
Register 0x42 - Value 0X12 - Bits 00010010
...
The thread 0xec4 has exited with code 0 (0x0).
The thread 0x868 has exited with code 0 (0x0).
22:21:47-RX PacketSnr 9.8 Packet RSSI -80dBm RSSI -122dBm = 59 byte message "�LoRaIoT1Maduino2at 62.8,ah 77,wsa 1,wsg 3,wd 34.88,r 0.00,"
22:21:52-TX 31 byte message Hello from AdaFruitIOLoRa ! 255
22:21:52-TX Done
The thread 0xbf8 has exited with code 0 (0x0).
The program '[3380] backgroundTaskHost.exe' has exited with code -1 (0xffffffff).

Next step modify my Adafruit IO and Azure IoT Hub/Central field gateways.

Adafruit LoRa Radio Bonnet with OLED – RadioFruit

Today a package arrived from Adafruit which contained an Adafruit LoRa Radio Bonnet 868 or 915MHz with OLED RFM95W.

The shield has a small OLED screen and 3 buttons connected to General Purpose Input Output(GPIO) pins.

The first step was to check the pin assignments of the 3 buttons.

/*
    Copyright ® 2019 Feb devMobile Software, All Rights Reserved
 
    MIT License

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all
    copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    SOFTWARE

	 Adafruit documentation page
	 https://learn.adafruit.com/adafruit-radio-bonnets/pinouts

    Button 1: GPIO 5 
    Button 2: GPIO 6
    Button 3: GPIO 12 

 */
namespace devMobile.IoT.Rfm9x.AdafruitButtons
{
	using System;
	using System.Diagnostics;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Gpio;

	public sealed class StartupTask : IBackgroundTask
    {
		private BackgroundTaskDeferral backgroundTaskDeferral = null;
		private GpioPin InterruptGpioPin1 = null;
		private GpioPin InterruptGpioPin2 = null;
		private GpioPin InterruptGpioPin3 = null;
		private const int InterruptPinNumber1 = 5;
		private const int InterruptPinNumber2 = 6;
		private const int InterruptPinNumber3 = 12;
		private readonly TimeSpan debounceTimeout = new TimeSpan(0, 0, 15);


		public void Run(IBackgroundTaskInstance taskInstance)
        {
			Debug.WriteLine("Application startup");

			try
			{
				GpioController gpioController = GpioController.GetDefault();

				InterruptGpioPin1 = gpioController.OpenPin(InterruptPinNumber1);
				InterruptGpioPin1.SetDriveMode(GpioPinDriveMode.InputPullUp);
				InterruptGpioPin1.ValueChanged += InterruptGpioPin_ValueChanged; ;

				InterruptGpioPin2 = gpioController.OpenPin(InterruptPinNumber2);
				InterruptGpioPin2.SetDriveMode(GpioPinDriveMode.InputPullUp);
				InterruptGpioPin2.ValueChanged += InterruptGpioPin_ValueChanged; ;

				InterruptGpioPin3 = gpioController.OpenPin(InterruptPinNumber3);
				InterruptGpioPin3.SetDriveMode(GpioPinDriveMode.InputPullUp);
				InterruptGpioPin3.ValueChanged += InterruptGpioPin_ValueChanged; ;

				Debug.WriteLine("Digital Input Interrupt configuration success");
			}
			catch (Exception ex)
			{
				Debug.WriteLine($"Digital Input Interrupt configuration failed " + ex.Message);
				return;
			}

			//enable task to continue running in background
			backgroundTaskDeferral = taskInstance.GetDeferral();
		}

		private void InterruptGpioPin_ValueChanged(GpioPin sender, GpioPinValueChangedEventArgs args)
		{
			Debug.WriteLine($"Digital Input Interrupt {sender.PinNumber} triggered {args.Edge}");
		}
	}
}

When I ran the application it produced the following output when I pressed the three buttons (left->right) which confirmed I had the correct GPIO pins configuration.

Application startup
'backgroundTaskHost.exe' (CoreCLR: CoreCLR_UWP_Domain): Loaded 'C:\Data\Programs\WindowsApps\Microsoft.NET.CoreFramework.Debug.2.2_2.2.27129.1_arm__8wekyb3d8bbwe\System.Runtime.WindowsRuntime.dll'. Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
Digital Input Interrupt configuration success
Digital Input Interrupt 5 triggered FallingEdge
Digital Input Interrupt 5 triggered RisingEdge
Digital Input Interrupt 6 triggered FallingEdge
Digital Input Interrupt 6 triggered RisingEdge
Digital Input Interrupt 12 triggered FallingEdge
Digital Input Interrupt 12 triggered RisingEdge

The next step was to get the Serial Peripheral Interface (SPI) interface for the module working.

/*
    Copyright ® 2019 Feb devMobile Software, All Rights Reserved
 
    MIT License

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all
    copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    SOFTWARE

	 Adafruit documentation page
	 https://learn.adafruit.com/adafruit-radio-bonnets/pinouts

	 CS : CE1
	 RST : GPIO25
	 IRQ : GPIO22 (DIO0)
	 Unused : GPIO23 (DIO1)
	 Unused : GPIO24 (DIO2)
 */
namespace devMobile.IoT.Rfm9x.AdafruitSPI
{
	using System;
	using System.Diagnostics;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Spi;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
			SpiController spiController = SpiController.GetDefaultAsync().AsTask().GetAwaiter().GetResult();
			var settings = new SpiConnectionSettings(1)
			{
				ClockFrequency = 500000,
				Mode = SpiMode.Mode0,   // From SemTech docs pg 80 CPOL=0, CPHA=0
			};

			SpiDevice Device = spiController.GetDevice(settings);

			while (true)
			{
				byte[] writeBuffer = new byte[] { 0x42 }; // RegVersion
				byte[] readBuffer = new byte[1];

				Device.TransferSequential(writeBuffer, readBuffer);

				byte registerValue = readBuffer[0];
				Debug.WriteLine("Register 0x{0:x2} - Value 0X{1:x2} - Bits {2}", 0x42, registerValue, Convert.ToString(registerValue, 2).PadLeft(8, '0'));

				Thread.Sleep(10000);
			}
		}
	}
}

The output confirm the code worked

'backgroundTaskHost.exe' (CoreCLR: CoreCLR_UWP_Domain): Loaded 'C:\Data\Programs\WindowsApps\Microsoft.NET.CoreFramework.Debug.2.2_2.2.27129.1_arm__8wekyb3d8bbwe\System.Threading.Thread.dll'. Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010

The next step is to build support for this shield into my RFM9X.IoTCore library and get the OLED working.

Uputronics Raspberry Pi+ LoRa(TM) Expansion Board

The second package to arrive was a Raspberry Pi+ LoRa(TM) Expansion Board populated with HopeRF 434MHz & 915MHz modules. It was in a small cardboard box with bolts+spacers and had a small set of printed instructions.

The shield has four user controlable Light Emitting Diodes(LED) connected to General Purpose Input Output(GPIO) pins which will be useful  for providing feedback when trying to debug faults etc..

uputronicsPiPlusHelp

Some of the pin numbers are also printed on the shield silk screen.UputronicsRPIPlusShield
This time the first step was to check the pin assignments of the 4 LEDs

//---------------------------------------------------------------------------------
// Copyright (c) September 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.UputronicsRPIPlusLed
{
	using System;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Gpio;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
			GpioController gpioController = GpioController.GetDefault();

			GpioPin ce01LedPin = gpioController.OpenPin(5);
			ce01LedPin.SetDriveMode(GpioPinDriveMode.Output);
			ce01LedPin.Write(GpioPinValue.Low);

			GpioPin ceo2LedPin = gpioController.OpenPin(21);
			ceo2LedPin.SetDriveMode(GpioPinDriveMode.Output);
			ceo2LedPin.Write(GpioPinValue.High);

			GpioPin lanLedPin = gpioController.OpenPin(6);
			lanLedPin.SetDriveMode(GpioPinDriveMode.Output);
			lanLedPin.Write(GpioPinValue.Low);

			GpioPin internetLedPin = gpioController.OpenPin(13);
			internetLedPin.SetDriveMode(GpioPinDriveMode.Output);
			internetLedPin.Write(GpioPinValue.High);

			while (true)
			{
				if (ce01LedPin.Read() == GpioPinValue.High)
				{
					ce01LedPin.Write(GpioPinValue.Low);
				}
				else
				{
					ce01LedPin.Write(GpioPinValue.High);
				}

				if (ceo2LedPin.Read() == GpioPinValue.High)
				{
					ceo2LedPin.Write(GpioPinValue.Low);
				}
				else
				{
					ceo2LedPin.Write(GpioPinValue.High);
				}

				if (lanLedPin.Read() == GpioPinValue.High)
				{
					lanLedPin.Write(GpioPinValue.Low);
				}
				else
				{
					lanLedPin.Write(GpioPinValue.High);
				}

				if (internetLedPin.Read() == GpioPinValue.High)
				{
					internetLedPin.Write(GpioPinValue.Low);
				}
				else
				{
					internetLedPin.Write(GpioPinValue.High);
				}

				Thread.Sleep(500);
			}
		}
	}
}

I think there is a small issue with the internet LED it should be GPIO13 (which matches the pin number)

The next step was to get the Serial Peripheral Interface (SPI) interface for both modules working.

//---------------------------------------------------------------------------------
// Copyright (c) September 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.UputronicsRPIPlusSPI
{
	using System;
	using System.Diagnostics;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Spi;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
#if CS0
			const int chipSelectPinNumber = 0;
#endif
#if CS1
			const int chipSelectPinNumber = 1;
#endif
			SpiController spiController = SpiController.GetDefaultAsync().AsTask().GetAwaiter().GetResult();
			var settings = new SpiConnectionSettings(chipSelectPinNumber)
			{
				ClockFrequency = 500000,
				Mode = SpiMode.Mode0,   // From SemTech docs pg 80 CPOL=0, CPHA=0
			};
			SpiDevice Device = spiController.GetDevice(settings);

			while (true)
			{
				byte[] writeBuffer = new byte[] { 0x42 }; // RegVersion
				byte[] readBuffer = new byte[1];

				// Read the RegVersion silicon ID to check SPI works
				Device.TransferSequential(writeBuffer, readBuffer);

#if CS0
				Debug.WriteLine("CS0 Register RegVer 0x{0:x2} - Value 0X{1:x2} - Bits {2}", writeBuffer[0], readBuffer[0], Convert.ToString(readBuffer[0], 2).PadLeft(8, '0'));
#endif
#if CS1
				Debug.WriteLine("CS1 Register RegVer 0x{0:x2} - Value 0X{1:x2} - Bits {2}", writeBuffer[0], readBuffer[0], Convert.ToString(readBuffer[0], 2).PadLeft(8, '0'));
#endif
				Thread.Sleep(10000);
			}
		}
	}
}

Like the other uputronics shield I have tested this appears not to have the reset line of the RFM9X connected.

The output confirmed the code worked with both CS0 and CS1 defined

CS0 Register RegVer 0x42 - Value 0X12 - Bits 00010010
CS0 Register RegVer 0x42 - Value 0X12 - Bits 00010010
CS0 Register RegVer 0x42 - Value 0X12 - Bits 00010010
CS0 Register RegVer 0x42 - Value 0X12 - Bits 00010010

 

CS1 Register RegVer 0x42 - Value 0X12 - Bits 00010010
CS1 Register RegVer 0x42 - Value 0X12 - Bits 00010010
CS1 Register RegVer 0x42 - Value 0X12 - Bits 00010010

Would have been more useful to read RegFrMsb = 0x06, RegFrMid = 0x7, and RegFrLsb = 0x08 so I could see the different default frequencies of the two HopeRF modules. The next step is to build support for this shield into my RFM9X.IoTCore library.

Uputronics Raspberry PiZero LoRa(TM) Expansion Board

During the week another couple of Raspberry PI2/3/Zero shields arrived from uputronics. The two Raspberry PiZero LoRa(TM) Expansion Boards had arrived earlier so I unpacked them first. They were in small cardboard boxes with bolts+spacers and had a small set of printed instructions which was quite professional.uputronicsPiZeroLoRaHelp.png
These shields also have a switch for configuring the chip select line which is quite a neat feature and means they can be stacked. Unlike the other shields I have tested these appear not to have the reset line of the RFM9X connected.

UputronicsRPIZeroShield

The first step was to get the SPI connectivity sorted

//---------------------------------------------------------------------------------
// Copyright (c) August 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.UputronicsRPZeroSPI
{
	using System;
	using System.Diagnostics;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Spi;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
#if CS0
			const int chipSelectPinNumber = 0;
#endif
#if CS1
			const int chipSelectPinNumber = 1;
#endif
			SpiController spiController = SpiController.GetDefaultAsync().AsTask().GetAwaiter().GetResult();
			var settings = new SpiConnectionSettings(chipSelectPinNumber)
			{
				ClockFrequency = 500000,
				Mode = SpiMode.Mode0,   // From SemTech docs pg 80 CPOL=0, CPHA=0
			};
			SpiDevice Device = spiController.GetDevice(settings);

			while (true)
			{
				byte[] writeBuffer = new byte[] { 0x42 }; // RegVersion
				byte[] readBuffer = new byte[1];

				// Read the RegVersion silicon ID to check SPI works
				Device.TransferSequential(writeBuffer, readBuffer);

				Debug.WriteLine("Register RegVer 0x{0:x2} - Value 0X{1:x2} - Bits {2}", writeBuffer[0], readBuffer[0], Convert.ToString(readBuffer[0], 2).PadLeft(8, '0'));

				Thread.Sleep(10000);
			}
		}
	}
}

The output confirmed the code worked with both CS0 and CS1 defined

Register RegVer 0x42 - Value 0X12 - Bits 00010010
Register RegVer 0x42 - Value 0X12 - Bits 00010010
Register RegVer 0x42 - Value 0X12 - Bits 00010010
The program '[2144] backgroundTaskHost.exe' has exited with code -1 (0xffffffff).

The shield has two onboard Light Emitting Diodes (LEDs) so I wrote a simple test application to flash them alternately.

//---------------------------------------------------------------------------------
// Copyright (c) July 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.UputronicsRPZeroLed
{
	using System;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Gpio;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
			GpioController gpioController = GpioController.GetDefault();
			GpioPin dataLedPin = gpioController.OpenPin(13);
			dataLedPin.SetDriveMode(GpioPinDriveMode.Output);
			dataLedPin.Write(GpioPinValue.Low);
			GpioPin linkLedPin = gpioController.OpenPin(6);
			linkLedPin.SetDriveMode(GpioPinDriveMode.Output);
			linkLedPin.Write(GpioPinValue.High);

			while (true)
			{

				if (dataLedPin.Read() == GpioPinValue.High)
				{
					dataLedPin.Write(GpioPinValue.Low);
				}
				else
				{
					dataLedPin.Write(GpioPinValue.High);
				}

				if (linkLedPin.Read() == GpioPinValue.High)
				{
					linkLedPin.Write(GpioPinValue.Low);
				}
				else
				{
					linkLedPin.Write(GpioPinValue.High);
				}

				Thread.Sleep(500);
			}
		}
	}
}

The two LEDs are labelled Data and Link but the pin numbers in the documentation were for an RPI Zero so didn’t match the ones I had to configure in code for my RPI3.

Overall the shield was professionally packaged and appears well engineered.

M2M LoRaWan Gateway Shield for Raspberry Pi

This morning a 1 Channel LoRaWan Gateway Shield for Raspberry Pi arrived from M2M along with a Low power LoRaWan Node Model A328 and Low power oRaWan Node Model B1284.

First setup to get the LoRaWan Gateway Shield up and running on my Raspberry PI 3.

M2MLoRaShield

No schematics were available so I had to reverse engineer the configuration for the Single Channel LoRaWAN Gateway for my Windows 10 IoT Core setup.

pins configuration in global_conf.json

“pin_nss”: 6,

“pin_dio0”: 7,

“pin_rst”: 0

If you use RPI0, edit single_chan_pkt_fwd.cpp and change eth0 to wlan0.

First step was to confirm I had the chip select line and SPI configuration sorted by reading the RegVersion register.

//---------------------------------------------------------------------------------
// Copyright (c) August 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.M2MSPI
{
	using System;
	using System.Diagnostics;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Gpio;
	using Windows.Devices.Spi;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
			GpioPin ChipSelectGpioPin = null;
			const int chipSelectPinNumber = 25;

			SpiController spiController = SpiController.GetDefaultAsync().AsTask().GetAwaiter().GetResult();
			var settings = new SpiConnectionSettings(1)
			{
				ClockFrequency = 500000,
				Mode = SpiMode.Mode0,   // From SemTech docs pg 80 CPOL=0, CPHA=0
			};

			// Chip select pin configuration
			GpioController gpioController = GpioController.GetDefault();
		   ChipSelectGpioPin = gpioController.OpenPin(chipSelectPinNumber);
			ChipSelectGpioPin.SetDriveMode(GpioPinDriveMode.Output);
			ChipSelectGpioPin.Write(GpioPinValue.High);

			SpiDevice Device = spiController.GetDevice(settings);

			while (true)
			{
				byte[] writeBuffer = new byte[] { 0x42 }; // RegVersion
				byte[] readBuffer = new byte[1];

				// Read the RegVersion silicon ID to check SPI works
				ChipSelectGpioPin.Write(GpioPinValue.Low);
				Device.TransferSequential(writeBuffer, readBuffer);
				ChipSelectGpioPin.Write(GpioPinValue.High);
				Debug.WriteLine("Register RegVer 0x{0:x2} - Value 0X{1:x2} - Bits {2}", writeBuffer[0], readBuffer[0], Convert.ToString(readBuffer[0], 2).PadLeft(8, '0'));

				Thread.Sleep(10000);
			}
		}
	}
}

The output confirmed I could read the register

‘backgroundTaskHost.exe’ (CoreCLR: CoreCLR_UWP_Domain): Loaded ‘C:\Data\Users\DefaultAccount\AppData\Local\DevelopmentFiles\M2MSPI-uwpVS.Debug_ARM.Bryn.Lewis\System.Threading.Thread.dll’. Skipped loading symbols. Module is optimized and the debugger option ‘Just My Code’ is enabled.
Register RegVer 0x42 – Value 0X12 – Bits 00010010
Register RegVer 0x42 – Value 0X12 – Bits 00010010

So far the M2M shield looks like a well priced option for my DIY LoRa Gateway deployments.

It arrived promptly and the vendor followed up with sample Arduino code a couple of days after the package shipped.

 

Electronic Tricks Lora/LoraWan shield for Raspberry Pi Zero and PI3

For the example code so far I had been using the Dragino LoRa GPS HAT for Raspberry PI which, after looking at the schematic (to figure out how the chip select line was connected) worked pretty well.

I had also purchased a Lora/LoRaWAN shield for Raspberry PI Zero and PI3 from Tindie (plus some unpopulated printed circuit boards so I can try building a RFM69HCW based shield).

The board didn’t fit on my Raspberry PI 2 & 3 devices so I used a Dexter industries Grove PI0 Shield as a temporary spacer to lift the antenna connector above the USB sockets.

The RFM95 chip select line is connected to pin 24 (GPIO8), the reset line to pin 29(GPIO5) and the interrupt line (RFM95 DIO0) to pin 22(GPIO25).

ElectronicTricksRFM95

My board doesn’t have any Light Emitting Diodes (LEDs) so it was straight into reading register values

//---------------------------------------------------------------------------------
// Copyright (c) July 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.ElectronicTricksSPI
{
	using System;
	using System.Diagnostics;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Spi;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
			SpiController spiController = SpiController.GetDefaultAsync().AsTask().GetAwaiter().GetResult();
			var settings = new SpiConnectionSettings(0) // GPIO8 Electronic Tricks
			{
				ClockFrequency = 500000,
				Mode = SpiMode.Mode0,   // From SemTech docs pg 80 CPOL=0, CPHA=0
			};

			SpiDevice Device = spiController.GetDevice(settings);

			while (true)
			{
				byte[] writeBuffer = new byte[] { 0x42 }; // RegVersion
				byte[] readBuffer = new byte[1];

				Device.TransferSequential(writeBuffer, readBuffer);

				byte registerValue = readBuffer[0];
				Debug.WriteLine("Register 0x{0:x2} - Value 0X{1:x2} - Bits {2}", 0x42, registerValue, Convert.ToString(registerValue, 2).PadLeft(8, '0'));

				Thread.Sleep(10000);
			}
		}
	}
}

The debug output confirmed I was reading the right value from the RegVer register

Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010

The antenna connector not clearing the USB socket is an issue which I’ll solve with a socket like the one on the GrovePI which has longer leads and acts as a spacer.
ElectronicTricksLoraShield

Elecrow Lora RFM95 IOT Board for RPI

For the example code so far I had been using the Dragino LoRa GPS HAT for Raspberry PI which after looking at the schematic (to figure out how the chip select line was connected) worked pretty well.

I had also purchased a Lora RFM95 IOT Board for RPI from Elecrow and was keen to get that working for applications which don’t require Global Positioning System (GPS) support.

The RFM95 chip select line is connected to pin 26 (GPIO7), the reset line to pin 15(GPIO22) and the interrupt line (RFM96 DIO0) to pin 22(GPIO25).

Lora RFM95 IOT Board for RPI V1.0

The shield had a Light Emitting Diode (LED) connected to General Purpose Input Output (GPIO) 23 so the first step was to get that to flash.

//---------------------------------------------------------------------------------
// Copyright (c) July 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.ElecrowLed
{
	using System;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Gpio;

	public sealed class StartupTask : IBackgroundTask
	{
		public void Run(IBackgroundTaskInstance taskInstance)
		{
			GpioController gpioController = GpioController.GetDefault();
			GpioPin yellowLedPin = gpioController.OpenPin(23);
			yellowLedPin.SetDriveMode(GpioPinDriveMode.Output);

			while (true)
			{
				if (yellowLedPin.Read() == GpioPinValue.High)
				{
					yellowLedPin.Write(GpioPinValue.Low);
				}
				else
				{
					yellowLedPin.Write(GpioPinValue.High);
				}
				Thread.Sleep(500);
			}
		}
	}
}

To confirm I could access the RMF95 registers over the Serial Peripheral Interface (SPI) I read the RegVersion register.

//---------------------------------------------------------------------------------
// Copyright (c) July 2018, devMobile Software
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.ElecrowSPI
{
	using System;
	using System.Diagnostics;
	using System.Threading;
	using Windows.ApplicationModel.Background;
	using Windows.Devices.Spi;

	public sealed class StartupTask : IBackgroundTask
    {
		public void Run(IBackgroundTaskInstance taskInstance)
		{
			SpiController spiController = SpiController.GetDefaultAsync().AsTask().GetAwaiter().GetResult();
			var settings = new SpiConnectionSettings(1)	// GPIO7 Elecrow shield
			{
				ClockFrequency = 500000,
				Mode = SpiMode.Mode0,	// From SemTech docs pg 80 CPOL=0, CPHA=0
			};

			SpiDevice Device = spiController.GetDevice(settings);

			while (true)
			{
				byte[] writeBuffer = new byte[] { 0x42 }; // RegVersion
				byte[] readBuffer = new byte[1];

				Device.TransferSequential(writeBuffer, readBuffer);

				byte registerValue = readBuffer[0];
				Debug.WriteLine("Register 0x{0:x2} - Value 0X{1:x2} - Bits {2}", 0x42, registerValue, Convert.ToString(registerValue, 2).PadLeft(8, '0'));

				Thread.Sleep(10000);
			}
		}
	}
}

The debug output confirmed I was reading the right value from the RegVer register

Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010
Register 0x42 - Value 0X12 - Bits 00010010

I’m going to unsolder the coil antenna and replace it with a short SMA Extension drop cable so I can connect an external antenna.

ElecrowLoRaShield