Failure is an option
After getting basic connectivity for my Seeedstudio LoRa-E5 Development Kit and Fezduino test rig working I started to build a general purpose library for GHI Electronics TinyCLR powered devices.
The code currently isn’t very robust so when I accidentally used an invalid region, then AppEUI the responses weren’t consistent. When the region configuration failed the response was +DR: ERROR(-1) which maps to “Parameters is invalid” and when the Join failed the response was “+JOIN: Join failed”.
// Set the Region to AS923
txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes("AT+DR=AS924\r\n"));
Debug.WriteLine($"TX: DR {txByteCount} bytes");
Thread.Sleep(500);
//Read the response
rxByteCount = serialDevice.BytesToRead;
if (rxByteCount > 0)
{
byte[] rxBuffer = new byte[rxByteCount];
serialDevice.Read(rxBuffer);
Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
}
In the Visual Studio 2019 Debug output window
The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.SeeedE5.NetworkJoinOTAA starting
TX: DR 13 bytes
RX :+DR: ERROR(-1)
When I tried an invalid AppEui and the AT+JOIN failed the error message was “+JOIN: Join failed”
In the Visual Studio 2019 Debug output window
devMobile.IoT.SeeedE5.NetworkJoinOTAA starting
TX: DR 13 bytes
RX :+DR: AS923
TX: MODE 16 bytes
RX :+MODE: LWOTAA
TX: ID=AppEui 40 bytes
RX :+ID: AppEui, 00:00:00:00:00:00:00:00
TX: KEY=APPKEY 48 bytes
RX :+KEY: APPKEY 01234567890123456789012345678901
TX: PORT 11 bytes
RX :+PORT: 1
TX: JOIN 9 bytes
RX :+JOIN: Start
+JOIN: NORMAL
+JOIN: Join failed
+JOIN: Done
I had to add some code to the SerialDevice_DataReceived method for handling the “+JOIN: Join failed” case. It would be good if the Seeedstudio LoRa-E5 reported errors in a consistent way for all commands, without the ERROR(..) marker.
