Why Flash the OTA Bootloader on a MeshCore Repeater?

When a MeshCore repeater is installed on a tower, roof, or other hard-to-reach location, updating the firmware the traditional way via USB cable can be difficult as you have to take the device down, update, and redeploy it. Luckily, there's an easy way to update using the Over-The-Air (OTA) update method. For NRF52 based devices like the Seeed Studio SenseCAP Solar Node P1‑Pro, this is done via the Bluetooth connection.

Installing the OTA Bootloader greatly reduces this risk. With it installed:

• Failed Bluetooth firmware updates result in a soft failure, not a device lockup.
• The repeater remains accessible so you can retry the update remotely.
• You can maintain deployed MeshCore nodes without climbing towers or rooftops.

For anyone deploying MeshCore repeaters in permanent or elevated locations, flashing the OTA Bootloader is highly recommended.

Now that you understand its purpose, follow the steps below to flash the OTA Bootloader and enable safer OTA firmware updates.

Step 1: Download the OTA Bootloader

The OTA Bootloader for the Seeed Studio SenseCAP Solar Node P1‑Pro can be found at the link below. Download it and take note of where it saves to.

Download OTA Bootloader (.uf2)

Step 2: Put the Repeater into DFU Mode and Flash the Bootloader

Hook up the repeater to a computer and put it into DFU mode by double-pressing the RST button (twice within half a second). The device will appear as a flash drive on your computer named XIAO-BOOT and will likely pop up a window with three files:

• CURRENT.UF2
• INDEX.HTM
• INFO_UF2.TXT

Keep this window open and open the folder where the OTA bootloader downloaded in another window. Find the file named update-xiao_nrf52840_ble_bootloader-0.9.2-OTAFIX2.1-BP1.2_nosd.uf2, right-click it, and select Copy. Go back to the XIAO-BOOT window, right-click on an empty area, and select Paste.

This will load the new bootloader onto the device and reboot it. The device will exit DFU mode and will no longer appear as a flash drive.

Step 3: Confirm that the OTA Bootloader was flashed

Put the device back into DFU mode by double-pressing the RST button again. The XIAO-BOOT flash drive should appear with the same three files:

• CURRENT.UF2
• INDEX.HTM
• INFO_UF2.TXT

Open the file named INFO_UF2.TXT and check if it has OTAFIX anywhere in the first line like the example below:

UF2 Bootloader 0.9.2-OTAFIX2.1-BP1.2 

Then the flashing process was a success and you now have a safe way to update your repeater's firmware over Bluetooth without having to climb!