Setting GNSS Device Path to GPSd?

Milosh · October 31, 2024, 4:01pm

Wanting to connect an external Ublox GPS to my gateway.

I have GPSd installed and configured and am getting valid GPS readings when connecting xGPS.

The 4.4.3 Concentratord release announcement says that this works " If GPSd has been configured (e.g. gnss_dev_path="gpsd://localhost:2947")"

But where do you actually set this line? Tried setting it in the overall Concentratord UCI to no avail. Do you have to set the global model flag in a particular way?

Thank You

Jason_Reiss · November 2, 2024, 2:51am

It is under [gateway] in the config template.

github.com

chirpstack/chirpstack-concentratord/blob/cb0f00cf335aff1f3c5731048298827da868bc0e/chirpstack-concentratord-sx1302/src/cmd/configfile.rs#L95


      
          # GNSS fix, use the system-time for setting the 'time' field on RX.
          time_fallback_enabled={{ gateway.time_fallback_enabled }}
          
          # Device and pin configuration.
          #
          # Only set this configuration if you need to override the default
          # configuration provided by the model configuration and you know
          # the device and pin mapping. In any other case, leave this commented
          # out.
          # gnss_dev_path="/dev/ttyAMA0"
          # gnss_dev_path="gpsd://localhost:2947"
          # com_dev_path="/dev/spidev0.0"
          # i2c_dev_path="/dev/i2c-1"
          # sx1302_reset_chip="/dev/gpiochip0"
          # sx1302_reset_pin=17
          # sx1302_power_en_chip="/dev/gpiochip0"
          # sx1302_power_en_pin=18
          # sx1261_reset_chip="/dev/gpiochip0"
          # sx1261_reset_pin=19

brocaar · November 5, 2024, 3:59pm

Please note that this might not 100% work as expected as you also need to wire the PPS signal from the GNSS module to the SX1301/2/3 module.

Milosh · November 5, 2024, 7:06pm

Is this something you can set through UCI? That’s not a directory I have been able to reach.

This is how I have it set on my machine and it does not appear to be working.

brocaar · November 18, 2024, 12:44pm

The RAK7289v2 Gateway OS image used Gpsd, see this config:

github.com

chirpstack/chirpstack-openwrt-feed/blob/master/chirpstack/chirpstack-concentratord-target-rak7289v2/files/chirpstack-concentratord-slot1.config#L15


      
          config sx1302
              option model            'rak_5146'
              option region           'EU868'
              option channel_plan     'eu868'
              option gnss             '1'
              option usb              '1'
              option antenna_gain     '2'
              option event_bind       'ipc:///tmp/concentratord_slot1_event'
              option command_bind     'ipc:///tmp/concentratord_slot1_command'
              option com_dev_path     '/dev/ttyACM0'
              option gnss_dev_path    'gpsd://localhost:2947'
              option sx1302_reset_pin '11'
          
          config 2g4
              option model            'rak_5148'
              option region           'ISM2400'
              option channel_plan     'ism2400'
              option antenna_gain     '2'
              option event_bind       'ipc:///tmp/concentratord_slot1_event'
              option command_bind     'ipc:///tmp/concentratord_slot1_command'
              option com_dev_path     '/dev/ttyACM0'

Again, this might not work in your case as with an external GPS module the PPS signal won’t be wired to the SX130X PPS pin.

LouneCode · November 20, 2024, 9:49pm

I have developed a new highly cost and power efficient solution for a ChirpStack compatible Gateway. Bill of components is about 100€ (here in Finland, including VAT and customs duty). This gateway has build-in GPS module. And yes, the PPS signal is wired to SX1303 chip. Gateway is powered by using PoE.

Fine timestamping seems to work with ChirpStack OK (used by geolocation resolver).

The project is in a very early stage and this new gateway solution has been running on testbed about couple days.

There is still work to be done. Time will tell if this solution works. But as I mentioned earlier, this is a very promising solution.

I’ll share more about this project if no major issues arise during the test period.

The first diagram shows a general overview of the components used in the solution.

Juan_Gomez_CoATI · January 6, 2025, 8:08am

Could you share the way to set the HT1303 in the chirpstak concentratord ?

LouneCode · January 6, 2025, 1:34pm

Hi,

Yes, I’ll share the complete package information for this new gateway. I’ll publish a repository concerning the GLStation hardware and software solutions. However, give me a little time to finish and polish the repository and the solution to make it good enough for publication.

I can already tell you that the configuration works well and is stable. The configuration is based on customized Alpine Linux firmware, and this base station now has the following properties:

Ethernet + POE
WLAN
GPS
Experimental Bluetooth GATT server for configuration purposes of the device
Built-in ChirpStack concentrator (with fine timestamps) and MQTT-forwarder

And that’s not all. I also have an experimental solution for 3D geolocation tracking based on Fine Timestamp and TDoA. It is capable of tracing LoRa sensors without GPS (GLSensor tracker + GLSensor3D). I’ll publish information about these ideas later.

LouneCode · January 6, 2025, 2:44pm

I have also designed a simply adapter pcb board for connecting MCU and HAT board together.

Adapter_pic

And there is experimental Bluetooth utility which help you find GLStation server after the first boot if it configured to use dynamic DHCP IP addresses. Utility tell you how to get the very first SSH connection to the server.

A mock version of the BT browser utility:

SSH-connection for the setup and admin tasks:

Juan_Gomez_CoATI · January 8, 2025, 8:34pm

Hi,

Thank you for your answer. I’ll waiting your publish. Meanwhile i appreciate if you could guide me with the settings in concentratord to set the HT1303 (if this is possible). I couldn’t make this work.

LouneCode · January 8, 2025, 10:41pm

Hi Juan,

My intention is to publish this concept what I have done for all parties who are interested in this new idea. It is much easier at the begin to do one guide for all than to advise everyone individually. I kindly ask for a little patience with this matter.

But yes, of course I’ll help you to get started.

Can you be more specific about what issues are problematic? There is lot of small details to work out If you refer that hw/software stack on the simplified diagram above. In that case, please wait a little for the release of this solution.

If the configuration/setup of the Chirpstack concentratord is only problem then answer is a very simple. You can use a basic configuration to starting point. The following lines are essential If you are using HT1303 card with USB interface:

sx1303.toml

.
.
.
  # Gateway vendor / model.
  #
  # This configures various vendor and model specific settings.
  model="semtech_sx1302css868gw1"

  # Gateway vendor / model flags.
  #
  # Flag can be used to configure additional vendor / model features. The
  # following flags can be used:
  #
  #   Global flags:
  #     GNSS - Enable GNSS / GPS support
  #     USB  - Use USB for concentrator communication (default is SPI)
  model_flags=["USB","GNSS"]
  
  # Device and pin configuration.
  # !!! Need GNNS model flag to be enabled --> model_flags=["USB","GNSS"]
  gnss_dev_path="gpsd://localhost:2947"
  # com_dev_path="/dev/ttyACM0"

.
.
.

TIP: The GPS device has a serial port interface that needs to be connected to the serial port of the MCU. The MCU should be able to run the Linux GPSD process.

Stacked construction of the MCU + HAT.

LouneCode · January 13, 2025, 2:43am

Here is GitHub link to the first “mock” version of the GLStation guide and firmware images.

I have built five GLStation gateway test units and so far everything seems to work as expected…

–
Cheers