Downlink Messages and SF Changes for Elvaco CMI 4160

[pmillart]

Thank you all for taking time to help me.
As indicated by @stevencellist I will try to move the gateway near the end device in the coming weeks to check if the issue is related to the antenna.
I will try to send a reboot command.
From the documentation I have to send 0x0022029E75 on FPort 2.
If it doesn’t work I will have to manually reboot the device.

If the device doesn’t handle well downlink. I’d like to understand if I can ask the netwok to completely disable ADR

@descartes thanks for your proposal for an endpoint. I might accept. I will keep your informed.

[pmillart]

Bonjour,

I wanted to provide an update on the issue I previously reported.

Due to lack of physical access to my device, I was unable to reboot it immediately. However, without any modifications on my end, the device eventually accepted one of the downlink commands and adjusted the Spreading Factor (SF) to 7. Since then, the device has been functioning perfectly.

The network continues to send downlink messages, which I suspect may be related to adjusting the TX power, although I couldn’t find detailed information on these events.

I can consider this issue resolved, though the exact cause of the resolution remains unclear. My key takeaways from this experience are:

• Let the Network Decide: Even if manual configuration seems possible, allowing the network to manage settings like ADR can be beneficial, as it may reduce unnecessary downlink messages.
• Patience and Rebooting: In cases where multiple downlink messages go unanswered, waiting a few days and then rebooting the device to force a new join can be an effective solution.

Thank you for your support throughout this process. I hope these insights might help others facing similar issues.

Patrick

[pmillart]

Just to add that I received a new adr request (in verbose mode on the console):
From this message I can see that the network asked for Data rate Index 5 => SF7
and Tx power 1 => decrease the transmission power

{
  "name": "ns.mac.link_adr.request",
  "time": "2024-08-12T09:37:19.534413521Z",
  "identifiers": [
    {
      "device_ids": {
        "device_id": "eui-94193a0103003e6b",
        "application_ids": {
          "application_id": "wil-sharky-775"
        },
        "dev_eui": "94193A0103003E6B",
        "join_eui": "94193A0303000001",
        "dev_addr": "260BC455"
      }
    }
  ],
  "data": {
    "@type": "type.googleapis.com/ttn.lorawan.v3.MACCommand.LinkADRReq",
    "data_rate_index": 5,
    "tx_power_index": 1,
    "channel_mask": [
      true,
      true,
      true,
      true,
      true,
      true,
      true,
      true,
      false,
      false,
      false,
      false,
      false,
      false,
      false,
      false
    ],
    "nb_trans": 1
  }

The message has been accepted on the next uplink

{
  "name": "ns.mac.link_adr.answer.accept",
  "time": "2024-08-12T10:07:19.054623543Z",
  "identifiers": [
    {
      "device_ids": {
        "device_id": "eui-94193a0103003e6b",
        "application_ids": {
          "application_id": "wil-sharky-775"
        },
        "dev_eui": "94193A0103003E6B",
        "join_eui": "94193A0303000001",
        "dev_addr": "260BC455"
      }
    }
  ],
  "data": {
    "@type": "type.googleapis.com/ttn.lorawan.v3.MACCommand.LinkADRAns",
    "channel_mask_ack": true,
    "data_rate_index_ack": true,
    "tx_power_index_ack": true
  }