Bluetooth tag setup and principles of work
1 Tag activation
Tags are always shipped with batteries(3V CR2032) but the batteries can be already installed or they need to be installed.
When you receive tags they are usually in special energy-saving mode. In this mode, check-in functionality is disabled. If you click on the tag button, it will blink 3 times without any sound. To activate a device you need to click on the button and hold on until the tag will blink additional 3 times (approximately 5 seconds). After that, the tag will be activated. Activation is finished within about 40s and there is a siren-like sound indicating it.
2 Correct sensor firmware (Parking Sensor G3)
Sensors must have appropriate firmware to support tag check-in functionality. Firmware name has “full check-in” in it (for example, “PS full check-in UK B1”). You can check current firmware and update sensors using Nwave Device Management App. Appropriate firmware for the EU and the US may be found here. You can check which band/frequency your base station uses via Nwave Console Base Stations.
3 Correct sensor firmware (Parking Sensor G4)
Sensors must have appropriate firmware to support tag check-in functionality. Firmware name has “full check-in” in it (for example, “PS full check-in EU B1”). You can check current firmware and update sensors using Nwave Device Management App. Appropriate firmware for the EU and the US may be found here. You can check which band/frequency your base station uses via Nwave Console Base Stations.
3 Properties of Parking Sensor firmware with BLE-tag support
Sensors with BLE-tag support have slightly increased power consumption to enable fast registration.
4 Check-in modes
There are 2 ways by which check-in request can be initiated:
automatically when a tag detects a vehicle stop;
manually by pressing the button.
4.1 Automatic check-in
To automatically initiate a check-in request a tag must initially detect that a vehicle is moving. In order to emulate vehicle movement just hold on it in your hand with a little shaking or rotation. In about 20 seconds there will be a short LED blink without any sound indicating that the tag has detected vehicle movement and now awaits for the vehicle to stop.
To emulate successful check-in put a mobile phone (as a replacement for a car) on top of the sensor’s center. The sensor must have good calibration so if it was moved it is necessary to calibrate it firstly using Nwave Device Management app.
After that, leave the tag close to the sensor. In approximately 15-20 seconds the tag will blink and beep (long sound about 1 second) indicating that there was successful check-in. If there are some sensors nearby but none of them is available for check-in the tag will blink and beep twice (short sound) in approximately 1 minute indicating failure. The indication will be only if there were some Nwave sensors with BLE tag check-in support nearby. If there are no sensors at all there will be no indication. It helps avoid disturbing users outside BLE tag check-in area.
A short YouTube video demonstrating automatic check-in operation: https://youtu.be/Wvv7OoQBwm8
4.2 Manual check-in
A user can also initiate check-in by click on the button on the tag. The tag acknowledges the user’s pressing by short blink and beep. Indication of success or failure will come a few seconds afterwards.
The main difference between the 2 ways to initiate check-in is that in case of failure of manual check-in the notification sound will be played even if there are no sensors nearby.
5 How to observe BLE tag registration messages using the Raw Messages page
5.1 UNB message format
When a tag successfully checks-in on a sensor, the sensor sends a special message with the tag ID to the cloud. To recognize these registration messages you need to find messages with the second byte of payload equal to FE as on the picture below. Bytes 4..7 contain big-endian 32-bit tag ID, so here the ID is AB000150.
5.2 LoRaWAN message format
When a tag successfully checks-in on a sensor, the sensor sends a special message with the tag ID to the cloud. To recognize these registration messages you need to find messages with the first byte of payload equal to 0A(first byte shows from which LoRaWAN port the message was received, so if you want to see this message in your LoRaWAN network it is port 10 and 5 bytes of data, the last 4 bytes are tag ID) as on the picture below. Bytes 3..6 contain big-endian 32-bit tag ID, so here the ID is AB00012C.
6 API Integration
https://nwaveio.atlassian.net/wiki/spaces/ND/pages/1976696950 is a great tool to test SDI APIs - they allow developers emulate tag registration events without using a physical hardware.
RabbitMQ: https://nwaveio.atlassian.net/wiki/spaces/ND/pages/1876918434 (auth_ble_tag)
7 Troubleshooting
Possible reasons for failure
The most common reasons for failure are:
there are no sensors with appropriate firmware nearby - check sensor’s firmware;
there are no recently (generally with occupation time less than 10 minutes) occupied sensors nearby.
Special cases
If there is a new check-in request (automatic or manual) from the same tag while the sensor nearby which was used to check-in previously and was not released (vacated) the tag will indicate successful check-in without the sensor sending an actual registration message as the tag assumes that the request was just a retry. So if you get successful tag check-in indication all the time without any registration messages in the cloud, try to look at all nearby sensors with tag support firmware and calibrate them (in order to vacate).