nRF Asset Tracker through Coiote flow

Module and data flow of the nRF Asset Tracker by its integration with Coiote from AVSystem

Modules

Links

• LwM2M
• Thingy:91 (firmware)
• Coiote Azure
• LwM2M converter lib
• nRF Asset Tracker

DATA

When data go through the module flow its change its form although refers to the same LwM2M definition.

In LwM2M the object 3 refers to Device and its resource 2 to the serial number. The firmware module uses the serial number of the device, which is the last value mentioned, but call it LWM2M_OBJECT_DEVICE_ID, 0, DEVICE_SERIAL_NUMBER_ID. Similar in the Coiote module, there this same value refers to 3.0.2 and in the LwM2M converter library it is 3.2. The most drastical change is in nRF Asset Tracker, where the variable name to refers to this value as imei.

Same situation happens for the rest of values of the nRF Asset Tracker input data. In order to provide clarity in this data transition, the following JSON was created; where keys represent the variable name in the nRF Asset Tracker module, values are the name in the firmware module and comments are how the object looks like in the LwM2M definition.

There are some values that were not able to find in this flow transition. Those are documented here:

missing values in json format

Data transicion

const dataTransicion = {
  cfg: {
    act: "CONFIGURATION_OBJECT_ID, 0, PASSIVE_MODE_RID", // 50009.0
    actwt: "CONFIGURATION_OBJECT_ID, 0, ACTIVE_WAIT_TIMEOUT_RID", // 50009.2
    mvres: "CONFIGURATION_OBJECT_ID, 0, MOVEMENT_RESOLUTION_RID", // 50009.3
    mvt: "CONFIGURATION_OBJECT_ID, 0, MOVEMENT_TIMEOUT_RID", // 50009.4
    loct: "CONFIGURATION_OBJECT_ID, 0, LOCATION_TIMEOUT_RID", // 50009.1
    accath: "CONFIGURATION_OBJECT_ID, 0, ACCELEROMETER_ACT_THRESHOLD_RID", // "50009.5"
    accith: "CONFIGURATION_OBJECT_ID, 0, ACCELEROMETER_INACT_THRESHOLD_RID", // 50009.8
    accito: "CONFIGURATION_OBJECT_ID, 0, ACCELEROMETER_INACT_TIMEOUT_RID", // 50009.9
    nod: [] // @see https://github.com/MLopezJ/nRF-Asset-Tracker-through-Coiote-flow/issues/2#issuecomment-1440102847
  },
  bat: {
    v: "LWM2M_OBJECT_DEVICE_ID, 0, POWER_SOURCE_VOLTAGE_RID", // 3.7
    ts: 1645072000000
  },
  env: {
    v: {
      temp: "IPSO_OBJECT_TEMP_SENSOR_ID, 0, SENSOR_VALUE_RID", // 3303.5700
      hum: "IPSO_OBJECT_HUMIDITY_SENSOR_ID, 0, SENSOR_VALUE_RID", // 3304.5700
      atmp: "IPSO_OBJECT_PRESSURE_ID, 0, SENSOR_VALUE_RID", //3323.5700 or 3315.5700 
      // @see https://github.com/MLopezJ/asset-tracker-cloud-coiote-azure-converter-js/issues/24
    },
    ts: 1645072000000,
  },
  gnss: {
    v: {
      lng: "LWM2M_OBJECT_LOCATION_ID, 0, LONGITUDE_RID", // 6.1
      lat: "LWM2M_OBJECT_LOCATION_ID, 0, LATITUDE_RID", // 6.0
      acc: "LWM2M_OBJECT_LOCATION_ID, 0, RADIUS_RID", // 6.3
      alt: "LWM2M_OBJECT_LOCATION_ID, 0, ALTITUDE_RID   ", // 6.2
      spd: "LWM2M_OBJECT_LOCATION_ID, 0, SPEED_RID", // 6.6
      hdg: "???????", // ***** Value is required in nRF Asset Tracker *****
    },
    ts: 1645072000000,
  },
  dev: {
    v: {
      imei: "LWM2M_OBJECT_DEVICE_ID, 0, DEVICE_SERIAL_NUMBER_ID", // 3.2
      iccid: "??????????, MODEM_ICCID", // ***** Value is required in nRF Asset Tracker *****
      modV: "LWM2M_OBJECT_DEVICE_ID, MODEM_FIRMWARE_VERSION", // 3.3
      brdV: LWM2M_OBJECT_DEVICE_ID, 0, MANUFACTURER_RID // 3.0
    },
    ts: 1645072000000,
  },
  roam: {
    v: {
      band: "???????", // ***** Value is required in nRF Asset Tracker *****
      nw: LWM2M_OBJECT_CONNECTIVITY_MONITORING_ID, 0, NETWORK_BEARER_ID, // 4.0
      rsrp: "LWM2M_OBJECT_CONNECTIVITY_MONITORING_ID,0,RSS", // 4.2
      area: "LWM2M_OBJECT_CONNECTIVITY_MONITORING_ID,0,LAC  ", // 4.12
      mccmnc:
        "LWM2M_OBJECT_CONNECTIVITY_MONITORING_ID,0,SMCC & LWM2M_OBJECT_CONNECTIVITY_MONITORING_ID,0,SMNC", //4.10 & 4.9
      cell: "LWM2M_OBJECT_CONNECTIVITY_MONITORING_ID,0,RSS", // 4.8
      ip: "LWM2M_OBJECT_CONNECTIVITY_MONITORING_ID,0,LAC    ", // 4.4
      eest: "???????", // ***** Value is required in nRF Asset Tracker *****
    },
    ts: 1645072000000,
  },
};

Process

1. Thingy:91 send data to Coiote Dashboard
2. Coiote transform data to coiote dialect
3. Azure receives the data
4. Data is transformed to LwM2M equivalent
5. Result of step 4 is checked against LwM2M types lib
6. If result of check is positive, the data is transformed to nRF Asset Tracker dialect. (to be implemented)
7. Result is send to web app.