AS923 Support

[Mandur]

Is your feature request related to a problem? Please describe.
Support of AS923 frequency range

Describe the solution you'd like
LoRa starter kit should support AS 923 freq range

Describe alternatives you've considered
N/A

Additional context
Requested by community

[jsaez868]

OK, so we figured we need to implement the new region in the RegionManager using https://lora-alliance.org/sites/default/files/2018-04/lorawantm_regional_parameters_v1.1rb_-_final.pdf as reference, correct?

[Mandur]

Hello! Thank you for the interest, yes you are Correct. I tried here below to list the changes needed to implement a new region. In case you have questions or you need additional help, I'd be happy to help you out.

• Add a region enum in LoraRegion
• Add correct mapping of downstream frequency in TryGetUpstreamChannelFrequency .
• most changes need to be done in RegionManager
  • We are using upstream frequency of first messages to detect current region. I would suggest changing max us frequencies to 915 and setting as range of 923-925 for the as region. TryResolveRegion
  • Create the region similarly to CreateEU868Region with adequate settings from the spec.
  • Add your new region to all the places where needed (like in TryTranslateToRegion

[jsaez868]

Hi @Mandur I've also sent you an invite to connect on Skype.

Here are my responses to your last post:

• Add a region enum in LoraRegion
  We've added new AS923 LoRaRegionType.

• Add correct mapping of downstream frequency in TryGetUpstreamChannelFrequency .
  We can't seem to find info about this on the specs. Does AS923 behave like EU868 region (respond on same frequency)?

• most changes need to be done in RegionManager

  • We are using upstream frequency of first messages to detect current region. I would suggest changing max us frequencies to 915 and setting as range of 923-925 for the as region. TryResolveRegion

  Should we set it to that range even if specs states the following?

  This section applies to regions where the frequencies [923…923.5MHz] are comprised...

  • Create the region similarly to CreateEU868Region with adequate settings from the spec.
    This is exactly what we did. For RX1DROffsetTable , did we do the following correctly:

        as923.RX1DROffsetTable = new int[1, 8]
        {
        { 0, 1, 2, 3, 4, 5, -1, -2 }
        };

• Add your new region to all the places where needed (like in TryTranslateToRegion
  We did this.

Based on our initial testing, C2D messages are still not making it downstream. On the log, I see the following being inferred/resolved by the kit incorrectly:

using device rx2: 0, datr: SF12BW125, region: AS923

Values used look incorrect - they should have been rx2dr = 2 and datr = SF10BW125.

Per specs => The RX2 receive window uses a fixed frequency and data rate. The default parameters are 923.2 MHz / DR2 (SF10/125KHz). which is what we've coded for the region:

new Region(
LoRaRegionType.AS923,
0x34,
ConversionHelper.StringToByteArray("C194C1"),
(frequency: 923.2, datr: 2),
1,
2,
5,
6,
16384,
64,
32,
(min: 1, max: 3));

How does the kit resolve the region to use for a downstream message? Using the last upstream message from the device (our device sends some sort of status/heartbeat message every hour)?

The log entry above seems to have come from the following lines of code in Region.cs:

            uint rx2Dr = (uint)rx2DrFromTwins;
            if (this.RegionLimits.IsCurrentDownstreamDRIndexWithinAcceptableValue(rx2Dr))
            {
                datr = this.DRtoConfiguration[rx2Dr].configuration;
                Logger.Log(devEUI, $"using device rx2: {rx2Dr}, datr: {datr}, region: {this.LoRaRegion}", LogLevel.Debug);
            }

RX2 value it's using seems incorrect. We've set the RX2DataRate property for the device twin to "2" - so it's in the desired properties but currently not in the reported properties. Our device is class C, ABP device.

These are the log entries from last hourly upstream message from the device:

2020-02-17 06:30:44.421 0000000000000007: device in cache
2020-02-17 06:30:44.421 0000000000000007: converted 16bit FCnt 99 to 32bit FCnt 99
2020-02-17 06:30:44.422 0000000000000007: ADR ack request received
2020-02-17 06:30:44.422 0000000000000007: calculated ADR: CanConfirmToDevice: True, TxPower: 7, DataRate: 5
2020-02-17 06:30:44.422 0000000000000007: device sent ADR ack request, computing an answer
2020-02-17 06:30:44.422 0000000000000007: down frame counter: 234
2020-02-17 06:30:44.422 0000000000000007: valid frame counter, msg: 99 server: 98
2020-02-17 06:30:44.422 0000000000000007: no decoder set in device twin. port: 9
2020-02-17 06:30:44.423 0000000000000007: sending message {"time":"2020-02-17T06:30:44.418394Z","tmms":0,"tmst":1511995188,"freq":923.2,"chan":0,"rfch":0,"stat":1,"modu":"LORA","datr":"SF8BW125","codr":"4/5","rssi":-57,"lsnr":11.5,"size":104,"data":{"value":"AQNAACoSAwsABBspAAAAAAAAAAjUAAATigAAAAAAAAEEAAAAAAAABtwAAAAAAIgBOC4YLhgAAAABAAAAAQAAAAEAAAABAAAAAQAAAAEAAAABAAAAAQAAAAEAig=="},"port":9,"fcnt":99,"rawdata":"AQNAACoSAwsABBspAAAAAAAAAAjUAAATigAAAAAAAAEEAAAAAAAABtwAAAAAAIgBOC4YLhgAAAABAAAAAQAAAAEAAAABAAAAAQAAAAEAAAABAAAAAQAAAAEAig==","eui":"0000000000000007","gatewayid":"loragw01","edgets":1581921044419} to hub
2020-02-17 06:30:44.461 0000000000000007: message '{"value":"AQNAACoSAwsABBspAAAAAAAAAAjUAAATigAAAAAAAAEEAAAAAAAABtwAAAAAAIgBOC4YLhgAAAABAAAAAQAAAAEAAAABAAAAAQAAAAEAAAABAAAAAQAAAAEAig=="}' sent to hub
2020-02-17 06:30:44.461 0000000000000007: checking cloud to device message for 00:00:00.5574438
2020-02-17 06:30:45.020 0000000000000007: done checking cloud to device message, found no message
2020-02-17 06:30:45.026 0000000000000007: error processing request: Index was outside the bounds of the array.
2020-02-17 06:30:45.027 0000000000000007: processing time: 00:00:00.6080537
2020-02-17 06:30:49.646 Physical dataUp {"rxpk":[{"tmst":1517220900,"time":"2020-02-17T06:30:49.644579Z","chan":0,"rfch":0,"freq":923.200000,"stat":1,"modu":"LORA","datr":"SF8BW125","codr":"4/5","lsnr":12.5,"rssi":-59,"size":104,"data":"gAMAABLAYwAJFrIut1ouqVkZc31G9zg+Qyj7wqT4Mw1gz7Smyu8iP4WIeVlASX117HCHi0AlWEjavxVYOB+046Tj4SX8FyxRwLfUeyLw0w2jMQoRKXWxkXF/C13BJEXEq6mhB46gKxI="}]}
2020-02-17 06:30:49.647 0000000000000007: device in cache
2020-02-17 06:30:49.647 0000000000000007: converted 16bit FCnt 99 to 32bit FCnt 99
2020-02-17 06:30:49.647 0000000000000007: resubmit from confirmed message detected, msg: 99 server: 99
2020-02-17 06:30:49.647 0000000000000007: ADR ack request received
2020-02-17 06:30:49.647 0000000000000007: calculated ADR: CanConfirmToDevice: True, TxPower: 7, DataRate: 5
2020-02-17 06:30:49.648 0000000000000007: device sent ADR ack request, computing an answer
2020-02-17 06:30:49.648 0000000000000007: down frame counter: 235
2020-02-17 06:30:49.648 0000000000000007: no decoder set in device twin. port: 9
2020-02-17 06:30:49.651 0000000000000007: checking cloud to device message for 00:00:00.5969923
2020-02-17 06:30:50.249 0000000000000007: done checking cloud to device message, found no message
2020-02-17 06:30:50.255 0000000000000007: processing time: 00:00:00.6105793
2020-02-17 06:30:50.255 0000000000000007: error processing request: Index was outside the bounds of the array.

The last downstream message we sent C2D logged the following entries, but it doesn't look like it reached the device since we didn't see expected result:

2020-02-17 06:47:32.340 0000000000000007: received cloud to device message from direct method: {"devEUI":"0000000000000007","fport":8,"rawPayload":"AQbfCgBkk/c=","confirmed":true}
2020-02-17 06:47:32.341 0000000000000007: [class-c] down frame counter: 236
2020-02-17 06:47:32.343 0000000000000007: using device rx2: 0, datr: SF12BW125, region: AS923
2020-02-17 06:47:32.344 0000000000000007: cloud to device message: 0106DF0A006493F7, id: undefined, fport: 8, confirmed: True, cidType: Zero
2020-02-17 06:47:32.345 0000000000000007: sending a downstream message with ID 09C9
2020-02-17 06:47:32.346 0000000000000007: ConfirmedDataDown {"txpk":{"imme":true,"data":"oAMAABIA7AAIPgfY4Sx+K9fOY0hM","tmst":0,"size":21,"freq":923.2,"rfch":0,"modu":"LORA","datr":"SF12BW125","codr":"4/5","powe":14,"ipol":true}}
2020-02-17 06:47:32.347 UDP: sending message with ID 5769, to 172.18.0.1:47169
2020-02-17 06:47:32.349 UDP: message sent with ID 5769

[jsaez868]

Here's the device twin info:

{
  "deviceId": "0000000000000007",
  "etag": "AAAAAAAAAAo=",
  "deviceEtag": "NjQ5MDEzMzYy",
  "status": "enabled",
  "statusUpdateTime": "0001-01-01T00:00:00Z",
  "connectionState": "Connected",
  "lastActivityTime": "2020-02-17T07:30:44.165017Z",
  "cloudToDeviceMessageCount": 0,
  "authenticationType": "sas",
  "x509Thumbprint": {
    "primaryThumbprint": null,
    "secondaryThumbprint": null
  },
  "version": 60,
  "properties": {
    "desired": {
      "AppSKey": "a8a6a0a7a6a9a8a8a0a1a0a8a8a8a0a0",
      "NwkSKey": "a8a6a0a7a6a9a8a8a0a1a0a8a8a8a0a0",
      "DevAddr": "12000003",
      "GatewayID": "loragw01",
      "SensorDecoder": "",
      "ClassType": "C",
      "RX1DROffset": 0,
      "FCntUpStart": 1,
      "FCntDownStart": 1,
      "FCntResetCounter": 1,
      "ABPRelaxMode": true,
      "RX2DataRate": 2,
      "$metadata": {
        "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
        "$lastUpdatedVersion": 10,
        "AppSKey": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "NwkSKey": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "DevAddr": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "GatewayID": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "SensorDecoder": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "ClassType": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "RX1DROffset": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "FCntUpStart": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "FCntDownStart": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "FCntResetCounter": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "ABPRelaxMode": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        },
        "RX2DataRate": {
          "$lastUpdated": "2020-02-15T20:17:55.0966586Z",
          "$lastUpdatedVersion": 10
        }
      },
      "$version": 10
    },
    "reported": {
      "PreferredGatewayID": "loragw01",
      "Region": "AS923",
      "FCntDown": 232,
      "FCntUp": 97,
      "FCntResetCounter": 1,
      "FCntUpStart": 1,
      "FCntDownStart": 1,
      "DataRate": 5,
      "NbRep": 1,
      "TxPower": 7,
      "$metadata": {
        "$lastUpdated": "2020-02-17T04:30:45.6044466Z",
        "PreferredGatewayID": {
          "$lastUpdated": "2020-02-07T04:04:38.7074891Z"
        },
        "Region": {
          "$lastUpdated": "2020-02-15T18:31:29.4094113Z"
        },
        "FCntDown": {
          "$lastUpdated": "2020-02-17T04:30:45.6044466Z"
        },
        "FCntUp": {
          "$lastUpdated": "2020-02-17T04:30:45.6044466Z"
        },
        "FCntResetCounter": {
          "$lastUpdated": "2020-02-07T05:14:39.4018464Z"
        },
        "FCntUpStart": {
          "$lastUpdated": "2020-02-07T18:04:38.1527326Z"
        },
        "FCntDownStart": {
          "$lastUpdated": "2020-02-07T18:04:38.1527326Z"
        },
        "DataRate": {
          "$lastUpdated": "2020-02-16T16:30:48.7563306Z"
        },
        "NbRep": {
          "$lastUpdated": "2020-02-15T21:30:55.1405018Z"
        },
        "TxPower": {
          "$lastUpdated": "2020-02-16T16:30:48.7563306Z"
        }
      },
      "$version": 50
    }
  },
  "capabilities": {
    "iotEdge": false
  }
}

[Mandur]

@jsaez868 Would you still be interrested in merging the AS923 frequency plan with upstream?