FAQ: 7. Other Questions:
7.1. Q: How to update nRF (RAK, T114, Seed XIAO) companion, repeater and room server firmware over the air using the new simpler DFU app?
A: The steps below work on both Android and iOS as nRF has made both apps' user interface the same on both platforms:
- Download nRF's DFU app from iOS App Store or Android's Play Store, you can find the app by searching for
nrf dfu, the app's full name isnRF Device Firmware Update - On https://flasher.meshcore.io, download the ZIP version of the firmware for your nRF device (e.g. RAK or Heltec T114 or Seeed Studio's Xiao)
- From the MeshCore app, login remotely to the repeater you want to update with admin privilege
- Go to the Command Line tab, type
start otaand hit enter. - you should see
OKto confirm the repeater device is now in OTA mode - Run the DFU app,tab
Settingson the top right corner - Enable
Packets receipt notifications, and changeNumber of Packetsto 10 for RAK, 8 for T114. 8 also works for RAK. - Select the firmware zip file you downloaded
- Select the device you want to update. If the device you want to update is not on the list, try enabling
OTAon the device again - If the device is not found, enable
Force Scanningin the DFU app - Tab the
Uploadto begin OTA update - If it fails, try turning off and on Bluetooth on your phone. If that doesn't work, try rebooting your phone. If you keep getting failures at the "Enabling Bootloader" step, try forgetting the NRF board in your IOS or Andriod device's bluetooth settings and re-pair it through the DFU app.
- Wait for the update to complete. It can take a few minutes.
- It is strongly recommended that you install and use the OTAFIX bootloader at https://github.com/oltaco/Adafruit_nRF52_Bootloader_OTAFIX.
- To update a companion node over OTA, it must be running companion firmware v1.15 or greater.
- Please see the Meshcore Blog for additional information on OTA firmware flashing:
- https://blog.meshcore.io/2026/04/06/otafix-bootloader
- https://blog.meshcore.io/2026/04/02/nrf-ota-update
7.1.1 Q: Can I update Seeed Studio Wio Tracker L1 Pro using OTA?
A: You can flash this safer bootloader to the Wio Tracker L1 Pro
https://github.com/oltaco/Adafruit_nRF52_Bootloader_OTAFIX
After this bootloader is flashed onto the device, you can trigger over the air update using bluetooth by holding the button next to the D-Pad and then click the reset button. The follow the same OTA update instructions above. You can skip pass the start ota instruction and start the update using the DFU app.
7.2. Q: How to update ESP32-based devices over the air?
A: For ESP32-based devices (e.g. Heltec V3):
- On https://flasher.meshcore.io, download the non-merged version of the firmware for your ESP32 device (e.g.
Heltec_v3_repeater-v1.6.2-4449fd3.bin, no"merged"in the file name) - From the MeshCore app, login remotely to the repeater you want to update with admin privilege
- Go to the Command Line tab, type
start otaand hit enter. - you should see
OKto confirm the repeater device is now in OTA mode - The command
start otaon an ESP32-based device starts a wifi hotspot namedMeshCore OTA - From your phone or computer connect to the 'MeshCore OTA' hotspot
- From a browser, go to http://192.168.4.1/update and upload the non-merged bin from the flasher
7.3. Q: Is there a way to lower the chance of a failed OTA device firmware update (DFU)?
A: Yes, developer che aporeps has an enhanced OTA DFU bootloader for nRF52 based devices. With this bootloader, if it detects that the application firmware is invalid, it falls back to OTA DFU mode so you can attempt to flash again to recover. This bootloader has other changes to make the OTA DFU process more fault tolerant.
Refer to https://github.com/oltaco/Adafruit_nRF52_Bootloader_OTAFIX for the latest information.
Currently, the following boards are supported:
- Heltec Automation Mesh Node T114 / HT-nRF5262
- Nologo ProMicro NRF52840 (aka SuperMini NRF52840)
- Seeed Studio SenseCAP Card Tracker T1000-E
- Seeed Studio Wio Tracker L1
- Seeed Studio XIAO nRF52840 BLE
- Seeed Studio XIAO nRF52840 BLE SENSE
- RAK 4631
- RAK WisMesh Tag (new 28/11/2025)
7.4. Q: are the MeshCore logo and font available?
A: Yes, it is on the MeshCore github repo here:
https://github.com/meshcore-dev/MeshCore/tree/main/logo
7.5. Q: What is the format of a contact or channel QR code?
A:
Channel:
meshcore://channel/add?name=&secret=
Contact:
meshcore://contact/add?name=&public_key=&type=
where &type is:
chat = 1
repeater = 2
room = 3
sensor = 4
7.6. Q: How do I connect to the companion via WIFI, e.g. using a heltec v3?
A:
WiFi firmware requires you to compile it yourself, as you need to set the wifi ssid and password.
Edit WIFI_SSID and WIFI_PWD in ./variants/heltec_v3/platformio.ini and then flash it to your device.
7.7. Q: I have a Station G2, or a Heltec V4, or an Ikoka Stick, or a radio with a EByte E22-900M30S or a E22-900M33S module, what should their transmit power be set to?
A:
For companion radios, you can set these radios' transmit power in the smartphone app. For repeater and room server radios, you can set their transmit power using the command line command set tx. You can get their current value using command line comand get tx
⚠️ WARNING: Set these values at your own risk. Incorrect power settings can permanently damage your radio hardware.
| Device / Model | Region / Description | In-App Setting (dBm) | Target Radio Output | Notes |
|---|---|---|---|---|
| Station G2 Reference | US915 Max Output | 19 dBm | 36.5 dBm (4.46W) | |
| US915 Max at 1dB compression point | 16 dBm | 35 dBm (3.16W) | 1dB compression point | |
| EU868 Max at 1dB compression point | 15 dBm | 34.5 dBm (2.82W) | 1dB compression point | |
| US915 1W Output | 10 dBm | 1W | Refer to your local government's requirements | |
| EU868 1W Output | 9 dBm | 1W | Refer to your local government's requirements | |
| Ikoka Stick E22-900M30S | 1W Model | 19 dBm | 1W | DO NOT EXCEED (Risk of burn out) data sheet |
| Ikoka Stick E22-900M33S | 2W Model | 9 dBm | 2W | DO NOT EXCEED (Risk of burn out) data sheet Refer to your local government's requirements |
| Heltec V4 | Standard Output | 10 dBm | 22 dBm (~0.15W) | |
| High Output | 22 dBm | 28 dBm (~0.5W to 0.6W) |
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