Helios-P Pressure Sensor
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      Helios-P Pressure Sensor NFC and Downlink Description

      Are you looking for the Helios-P NFC and downlink description to configure the sensor?

      How does the configuration of the Sentinum sensors via downlink and NFC (provisioning) work?

      💡 This documentation can be used for all sensors in the Sentinum series that have the NFC and downlink functions. It serves as generic documentation. The individual descriptions of the fields can be found in the respective links.

      Downlinks

      Basics of downlinks with Sentinum sensors

      📢 All downlinks of the Sentiface and Senticom module are scheduled on port 4, all commands of the supervisor module, such as resets, are scheduled on port 5.

      Like the payload, the downlink commands are divided into modules. The sensor merely acts as a container that manages and implements the commands. The downlinks can be used to configure the sensor for the specific application. In addition to the configurations, executing downlinks, such as a reset, can also be carried out. All commands are protected by minimum and maximum values so that no incorrect settings can be made. The structure is hierarchical and consists of the following elements:

      • Module
      • Group
      • Property
      • Command

      A module has several groups, which in turn are made up of several properties. The following table shows how the structure is generally organized:

      Modules and groups of the sensor

      📢 All downlinks of the Sentiface and Senticom module are scheduled on port 4, all commands of the supervisor module, such as resets, are scheduled on port 5.

      💡 Sentinum guarantees backwards compatibility within different subversions. This means that a Sentiface module with the key 0x1121 also accepts downlink commands with the key 0x1111.

      Structure of the module key

      💡 The module key of the SENTIFACE module can be taken from the first 2 bytes of each uplink.

      Example uplink: 11 11 06 1B E1 92 02 00 00 06 86

      💡 1111 forms the module key.
      The module key explained here only refers to the SENTIFACE module. 0x2111 should always be used as the module key for SENTICOM.

      Structure of a downlink command

      📢 The reset command is an exception. This is shown on page 9.

      📢 An alarm variable is usually set in the first data packet (uplink), as the value is compared with an internal reference value.

      Reset command via downlink

      The reset command must be executed in 2 steps or in 2 downlinks on port 5: First, the reset must be executed with the command[TOKEN] 31 11 01 01 and can then be focused with [TOKEN] 31 11 00 be triggered.

      Command HEX Description
      [TOKEN] 31 11 01 01 Reset Arm
      [TOKEN] 31 11 00 Reset the sensor

       

       

      NFC

      Basics

      In addition to downlinks, the sensor can also be configured with a smartphone app via NFC. The different configurations of the sensor are transferred as .JSON. The app offers an initial configuration option when the sensor is activated. In addition to the sensor settings, the app also enables the configuration of network parameters such as APPEUI and APPKEY. As with the downlink, the structure is hierarchical.

      Both the modules (module names) and alias names for the individual properties are important for the NFC configuration. The following table describes the available modules.

      Structure of a .json object

      Each sensor profile is transferred as a JSON object. Each object begins with { and ends with }. Additional objects can be integrated into an object. In general, objects contain an ordered list of properties separated by commas. A property is a key-value pair consisting of a unique key (character string) and a value (any element). The key and the value are separated by a colon (:). Let's take a look at the following example, which has been formatted:

      Untitled (100)As in the previous JSON example, the object follows a specific structure. The first key-value pair. If the sensor is deactivated (power = off), you can activate the sensor with its basic settings by loading an empty JSON, for example, and activating the sensor with the app. It is also possible to set settings during activation.

      💡 "power": "OFF" or "power": "ON" is a state of the sensor. The sensor responds to a command with off or on. "off" or "on" therefore does not represent a command.

      To restart the sensor (cf. restarting a PC), the "REBOOT" command must be written in the "power" field:

      {"power":"REBOOT"}

      After a few seconds, the sensor writes the value "ON" to the "power" field, indicating that the boot process is complete.

      Checking the operation of the sensor

      The "REBOOT" command can be used to check the functionality of the sensor. Overwrites the sensor. If the sensor does not overwrite the field after 15 seconds at the latest and remains in the {"power": "REBOOT"} state, an error has occurred. state, an error has occurred. This usually indicates flat batteries or a hardware defect.

      Activation, deactivation and app

      Activation takes place via an NFC app. A smartphone is required for this. The app can be downloaded from the respective app stores. Simply search for "Sentinum LinQs" and download the app.

      Untitled (29)

      💡 Now locate the NFC tag on the sensor. Depending on the type of smartphone, the reader can be at the top, in the middle or further down.

      Untitled (14)

      💡 The position of the NFC tag on the sensor can be found in the respective operating instructions or in the Quickstart Guide.

      📢 If keys such as app_eui and app_key are changed and then a REBOOT is executed, the original keys are set.

      📢 The power key is not assigned to a module group.

      You can find instructions for the NFC app here:

      TBD

      Further information on the NFC APP

      💡 There are read only (r), write only (w) and read&wirte (rw) keys and values. For example, keys can be protected.

      💡 If a profile is created and transmitted incorrectly, the previous settings are retained. This can happen, for example, if the JSON was created in the wrong format.

      💡 When compiling the profile, several module groups can be accessed at once or only individual module groups. The same applies to the properties.

      💡 In the latest version of the app, profiles can be created and saved. There will also be a function for reading out the sensors. In addition, data such as the location can be sent to a defined end point.

      Storage of values via downlink and NFCNFC

      💡 Values that are written to the NFC are also saved in the event of a reset or battery change and are retrieved by the sensor.

      💡 Values that are set via downlink can be transferred to the NFC tag with an additional downlink command.

      Sensor-specific NFC and downlink configurations

      CSQ und Empfang

      Value RSSI dBm Condition
      2 -109 Marginal
      3 -107 Marginal
      4 -105 Marginal
      5 -103 Marginal
      6 -101 Marginal
      7 -99 Marginal
      8 -97 Marginal
      9 -95 Marginal
      10 -93 OK
      11 -91 OK
      12 -89 OK
      13 -87 OK
      14 -85 OK
      15 -83 Good
      16 -81 Good
      17 -79 Good
      18 -77 Good
      19 -75 Good
      20 -73 Excellent
      21 -71 Excellent
      22 -69 Excellent
      23 -67 Excellent
      24 -65 Excellent
      25 -63 Excellent
      26 -61 Excellent
      27 -59 Excellent
      28 -57 Excellent
      29 -55 Excellent
      30 -53 Excellent

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

      Documentation Links

      You can find the links for the other Helios-P documentation here: