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Encoding a downlink message

The encoder takes the JSON format string and converts it into the downlink hexadecimal payload. Each downlink message must contain the following fields:

  • DownMessageType : Type of downlink messages (string format). Acceptable values are:

    • POS_ON_DEMAND : Request a position
    • SET_MODE : Change the operation mode of a tracker
    • START_SOS : Start the SOS mode
    • STOP_SOS : Stop the SOS mode
    • DEBUG_COMMAND : Send debug commands
    • SET_PARAM : Modify the tracker’s parameter or parameters
    • REQUEST_CONFIG : Read the tracker configuration
    • REQUEST_TEMPERATURE_STATUS : Request a temperature status

  • AckToken : Random integer ranging from 0 to 15 and used by the tracker to acknowledge the downlink message. For more information about setting and processing this field, see Asset Tracker Driver User Guide.

Notes

  • Each field name must be coded as a string.

  • Extra fields must be provided according to the downlink message type.

  • All types of messages are supported since Asset Tracker V1.7. However, some parameters are new since v1.8 or v1.9 in SET_PARAM, REQUEST_CONFIG, and DEBUG_COMMAND messages.

Example - Request a position​

  1. This message requests a position to the tracker, where "message" is the downlink request in JSON.


------------------------------ Snippet begin ------------------------------
curl -X POST \
  http://localhost:8095/iot-flow-driver/v1/encode \
  -H 'Content-Type: application/json' \
  -d '{
    "direction": "downlink",
    "meta": {},
    "thing": {
      "application": {
        "producerId": "abeeway",
        "moduleId": "asset-tracker",
        "version": "2"
      }
    },
    "message": {
      "downMessageType": "POS_ON_DEMAND",
      "ackToken": 10
  }
}'
------------------------------ Snippet End ------------------------------
  1. Here is the output of the driver results in the binary payload "010a" that can be sent to Abeeway tracker on LoRaWAN® downlink port number 2.
------------------------------ Snippet begin ------------------------------
{
  "direction": "downlink",
  "sourceTime": "2019-06-07T14:28:52.016Z",
  "meta": {
    "driverId": "abeeway:asset-tracker:2"
  },
  "raw": {
    "binary": "010a"
  },
  "message": {
    "DownMessageType": "POS_ON_DEMAND",
    "AckToken": 10
  },
  "thing": {
    "application": {
      "producerId": "abeeway",
      "moduleId": "asset-tracker",
      "version": "2"
    }
  }
}
------------------------------ Snippet end ------------------------------
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