nanoFramework RAK811 LoRaWAN library Part4

Nasty OTAA connect

After getting basic connectivity for my RAK811 LPWAN Evaluation Board(EVB) and STM32F691DISCOVERY test rig sorted. I wanted to see if I could get the device connected to The Things Network(TTN) via the RAK7246G LPWAN Developer Gateway which was on my desk. I had got the EVB configuration sorted with an Arduino Uno R3 device so I was confident it should work.

STM32F691Discovery with EVB plugged into Arduino headers

My Over the Air Activation(OTAA) implementation is pretty “nasty” I assumed that there would be no timeouts or failures and I only send one BCD message “48656c6c6f204c6f526157414e” which is “hello LoRaWAN”

I configured the RAK811 module for LoRaWAN

// Set the Working mode to LoRaWAN
bytesWritten = outputDataWriter.WriteString("at+set_config=lora:work_mode:0\r\n");
Debug.WriteLine($"TX: work_mode {outputDataWriter.UnstoredBufferLength} bytes to output stream.");
txByteCount = outputDataWriter.Store();
Debug.WriteLine($"TX: {txByteCount} bytes via {serialDevice.PortName}");

// Read the response
bytesRead = inputDataReader.Load(128);
if (bytesRead > 0)
{
   string response = inputDataReader.ReadString(bytesRead);
   Debug.WriteLine($"RX sync:{response}");
}

Then just sequentially stepped through the necessary configuration to join the TTN network

// Set the Region to AS923
bytesWritten = outputDataWriter.WriteString("at+set_config=lora:region:AS923\r\n");
Debug.WriteLine($"TX: region {outputDataWriter.UnstoredBufferLength} bytes to output stream.");
txByteCount = outputDataWriter.Store();
Debug.WriteLine($"TX: {txByteCount} bytes via {serialDevice.PortName}");

// Read the response
bytesRead = inputDataReader.Load(128);
if (bytesRead > 0)
{
   String response = inputDataReader.ReadString(bytesRead);
   Debug.WriteLine($"RX sync:{response}");
}

// Set the JoinMode
bytesWritten = outputDataWriter.WriteString($"at+set_config=lora:join_mode:0\r\n");
Debug.WriteLine($"TX: join_mode {outputDataWriter.UnstoredBufferLength} bytes to output stream.");
txByteCount = outputDataWriter.Store();
Debug.WriteLine($"TX: {txByteCount} bytes via {serialDevice.PortName}");

// Read the response
bytesRead = inputDataReader.Load(128);
if (bytesRead > 0)
{
   String response = inputDataReader.ReadString(bytesRead);
   Debug.WriteLine($"RX sync:{response}");
}

// OTAA set the devEUI
bytesWritten = outputDataWriter.WriteString($"at+set_config=lora:dev_eui:{devEui}\r\n");
Debug.WriteLine($"TX: dev_eui {outputDataWriter.UnstoredBufferLength} bytes to output stream.");
txByteCount = outputDataWriter.Store();
Debug.WriteLine($"TX: {txByteCount} bytes via {serialDevice.PortName}");

// Read the response
bytesRead = inputDataReader.Load(128);
if (bytesRead > 0)
{
   String response = inputDataReader.ReadString(bytesRead);
   Debug.WriteLine($"RX sync:{response}");
}
...

The code is not suitable for production but it confirmed my software and hardware configuration worked.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.Rak811.NetworkJoinOTAA starting
COM5,COM6
TX: work_mode 32 bytes to output stream.
TX: 32 bytes via COM6
RX sync:UART1 work mode: RUI_UART_NORAMAL
Current work_mode:LoRaWAN, join_mode:OTAA, Class: A
Initialization OK 

TX: region 33 bytes to output stream.
TX: 33 bytes via COM6
RX sync:OK 

TX: join_mode 32 bytes to output stream.
TX: 32 bytes via COM6
RX sync:OK 

TX: dev_eui 45 bytes to output stream.
TX: 45 bytes via COM6
RX sync:OK 

TX: app_eui 45 bytes to output stream.
TX: 45 bytes via COM6
RX sync:OK 

TX: app_key 61 bytes to output stream.
TX: 61 bytes via COM6
RX sync:OK 

TX: confirm 30 bytes to output stream.
TX: 30 bytes via COM6
RX sync:OK 

TX: join 9 bytes to output stream.
TX: 9 bytes via COM6
RX sync:
RX sync:
RX sync:
RX sync:
RX sync:OK Join Success

TX: send 43 bytes to output stream.
TX: 43 bytes via COM6
TX: send 43 bytes to output stream.
TX: 43 bytes via COM6
RX sync:OK 
at+recv=0,-59,9,0

In the Visual Studio 2019 debug out put I could see messages getting sent and then after a short delay they were visible in the TTN console.

I then modified the confirmed flag and in the TTN console I could see how they were processed differently.

Confirmed messages
Unconfirmed messages

I could receive messages but as the RAK 811 module can be configured to be a Class C device there didn’t appear to be a way to receive a message without sending one which seemed a bit odd.

The next step is to get Authentication By Personalisation(ABP) working.

2 thoughts on “nanoFramework RAK811 LoRaWAN library Part4

  1. Pingback: nanoFramework RAK811 LoRaWAN library Part5 | devMobile's blog

  2. Pingback: TinyCLR OS V2 RC1 RAK811 LoRaWAN library Part2 | devMobile's blog

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.