[Jason Reiss]

Yes, curl is available on mLinux.

[Jason Reiss]

Are you able to ssh to the device or login from the USB device port on the back?

[Jason Reiss]

The network server will not send a downlink unless you have ACK’s enabled. recv() is not necessary but can be used if you are expecting downlink data from the network server.

The rssi value is a property of the packet received by the dot. There will be no value until after a downlink.

[Jason Reiss]

You can check the currently installed version with:

> opkg list | grep lora

If the version is not at 1.4.1 r9, upgrade with the mLinux package.

AEP 1.1.2 should have that version installed by default.

[Jason Reiss]

Are you receiving a packet from the gateway?
What are the values being returned?

[Jason Reiss]

An application would monitor the join status.

getNetworkJoinStatus()

This will be set to false if the threshold is met.

[Jason Reiss]

The two interfaces are provided by the USB. One appears as a USB drive for the user to load new firmware (program), the other is the Virtual COM Port for serial debug messages (debug).

J6 mbed USB Connector , attaches to the ST Micro controller. This provides access to two interfaces, one used to program the mDot and the other for debug messages.

For example programs the baud rate of the serial port is not being configured by libmDot. libmDot holds a configuration baud rate for use by the AT Command firmware, it does not setup the serial for an application.

The default mbed baud rate 9600 is being used.

• This reply was modified 8 years, 10 months ago by Jason Reiss.

[Jason Reiss]

You will want to update the lora-network-server to 1.0.8
See the downloads page. This will also fix the init script that was modified for TTN.

[Jason Reiss]

Can you share your configuration?

On mDot
AT&V

On Conduit
Contents of /var/config/lora/lora-network-server.conf

Also you could try these commands to run the network server manually and see if there are errors in starting

> /etc/init.d/lora-network-server stop
> cd /opt/lora/
> ./lora-network-server -c /var/config/lora/lora-network-server.conf

[Jason Reiss]

That worked for me Bryan, thanks.

Just do not copy and paste from the post as the quotes are not “quotes”.

[Jason Reiss]

If you edit /etc/resolv.conf and add your dns servers there

nameserver 8.8.8.8

The resolv.conf file will be reset on reboot so you will have to change the file again.

It seems the dns-nameservers line in /etc/network/interfaces is not being applied on startup.

[Jason Reiss]

OK so you have the US version.

I was thrown by the typo in your post
AUS version

Please open a ticket at support.multitech.com to discuss AU/NZ options.

Also, I am not aware of an open source LoRaWAN library with NZ support.

[Jason Reiss]

Those are the correct instructions.

[Jason Reiss]

Is there an issue with the frequencies/settings used by your mDot/Conduit setup as you have them now?

[Jason Reiss]

You can perform the upgrade to mLinux 3.1.0.

Downloads

To use our LoRa Software update the network server, packet forwarder and lora-query found on the same page after the upgrade.

[Jason Reiss]

Guillermo,

I have done similar testing in order to investigate your RSSI results. We noticed a similar periodic drop in RSSI although the period was different. I then conducted the same test inside an anechoic/shielded chamber with filtered AC power and the period drop in RSSI disappeared. This leads me to believe there may be an environmental cause. I also note the SNR value reported by the gateway did not seem affected in these time periods.

If you have SNR data can you compare as well?

Thanks,

Jason

[Jason Reiss]

In EU868 LoRaWAN a full-duplex single gateway may not be possible as the gateway will respond on the same frequency in the first rx window and limited amount of spectrum does not allow sufficient frequency separation for RX2. So the downlink TX may still affect the reception of uplink packets as the TX antenna could overwhelm the RX antenna.

A half-duplex card where the rx/tx path is switched is desired in the EU868 because of this.

[Jason Reiss]

Guillermo,

Thank you for the detailed analysis.

The mCard has a spi interface to the SX1301 so the software interfacing with the concentrator chip is running on the main CPU. I will forward your results to the hardware team. The observed 14 hour cycle is most interesting.

As I have mentioned before we have noticed a decrease in PER when SF12 is used near the gateway. I suspect the increased redundancy is causing interference by multi-path effect and echos. The PER is less affected when run in an anechoic chamber.

mCard firmware and calibration firmware is loaded by the library.
Our default software is built from the Semtech gateway and packet forwarder with a few added tweaks. I would be interested in seeing your test scenarios run against the default Multitech software as well.
http://git.multitech.net/cgi-bin/cgit.cgi/lora_gateway.git/
https://github.com/Lora-net/packet_forwarder

Would you be able to also post your results to the open lora forum? It is run by the loriot team and they may be able to provide insight regarding their software functionality.
http://openlora.com

Please open a support ticket at support.multitech.com to further discuss your issues.

Sincerely,

Jason

[Jason Reiss]

Have you analyzed the PER when ACK is off?
Perhaps try SF10 instead of SF12 for another datapoint.

Thanks,

Jason

[Jason Reiss]

What version of AEP do you have installed?

The latest version of AEP and components can be found here:

Downloads

[Jason Reiss]

The things network poly-packet-forwarder can send packets to both. There is not a filter mechanism to direct certain packets either which way.

Packets from locally provisioned units would only be accessible with the keys shared with the Conduit and vice versa with packets destined for TTN.

[Jason Reiss]

Please feel free to open a support ticket at support.multitech.com. This will get better attention than the forum posts. The forum is meant to be a community where users help each other not an extension of our support portal. We try to help out here as much as we can.

[Jason Reiss]

Different SF settings should not interfere with each other.
How near the gateway is the SF7 node?
How near the gateway is the SF12 node? Distance < 20m can has impact on SF12 reception. Are there any downlink transmission from the gateway? ACK or otherwise. The mCard is a half-duplex design, any TX will toss an RX in progress. A single mCard is able to receive 8 packets simultaneously. Firmware are available in downloads. http://www.multitech.net/developer/downloads/ Check currently installed versions with: > opkg list
> opkg list | grep lora

[Jason Reiss]

The specification in use is today LoRaWAN 1.0.

LoRaMAC was a predecessor with specification versions up to v3.1. It appears you are looking at an old spec.

The LoRaWAN protocol exclusively uses duty-cycle to manage access to the medium.

From LoRaWAN 1.0

7 7.1.2 EU863-870 ISM Band channel frequencies 
... 
14 In order to access the physical medium the ETSI regulations impose some restrictions such 
15 maximum time the transmitter can be on or the maximum time a transmitter can transmit per 
16 hour. The ETSI regulations allow the choice of using either a duty-cycle limitation or a so- 
17 called Listen Before Talk Adaptive Frequency Agility (LBT AFA) transmissions 
18 management. The current LoRaWAN specification exclusively uses duty-cycled limited 
19 transmissions to comply with the ETSI regulations.

[Jason Reiss]

        /** Set network link check count to perform automatic link checks every count packets
         * only applicable if ACKs are disabled
         * @param count must be between 0 - 255
         * @returns MDOT_OK if success
         */
        int32_t setLinkCheckCount(const uint8_t& count);

        /** Get network link check count
         * @returns count (0 - 255)
         */
        uint8_t getLinkCheckCount();

        /** Set network link check threshold, number of link check failures or missed acks to tolerate
         * before considering network connection lost
         * @pararm count must be between 0 - 255
         * @returns MDOT_OK if success
         */
        int32_t setLinkCheckThreshold(const uint8_t& count);

[Jason Reiss]

Change your frequency sub band setting to 1 to match the frequencies setup on Conduit.

static uint8_t config_frequency_sub_band = 1;

Or modify conduit to use frequency sub band 4 to match mdot
Use 907400000 and 908200000 for radio_0 and radio_1 settings.

[Jason Reiss]

How is the end-point configured?

AT+FREQ?
FB_915

From the frequencies and synch word you would need these set.
AT+FSB=1
AT+PN=1

Can you enable logging and upload some debug output?
AT+LOG=6

Another option would be to use the things network poly-packet-forwarder.

[Jason Reiss]

There have been issues with mbed-rtos 117.
Rollback to a previous version. This should fix the join issue too.

[Jason Reiss]

I have seen it as well occasionally after flashing the unit with new firmware. A power cycle rather than reset will allow the RTC to be initialized.

[Jason Reiss]

There is no software available to support this. It would be a custom application running on the conduit.

Node-red could be used to listen for UDP packets from the forwarder and send them back to the forwarder with the key { “imme”: true } added to the packet.

For more details on downlink packet format see:
https://github.com/Lora-net/packet_forwarder/blob/master/PROTOCOL.TXT

[Author]

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