Advanced Firmware Options¶

EasySkyMesh: Power Saving Firmware¶

EasySkyMesh is a community project that provides optimized MeshCore firmware builds with power saving features, sensor integration, and experimental bug fixes ahead of the upstream MeshCore releases.

What It Offers¶

PowerSaving firmware: Reduces idle current draw significantly (as low as 15 mA on ESP32 BLE companions) while maintaining full mesh functionality
Sensor support: Attach environmental or infrastructure sensors to repeater nodes and transmit readings over the existing MeshCore network
Early features: Changes developed here are submitted upstream to the main MeshCore project

Flashing EasySkyMesh Firmware¶

Download the appropriate firmware binary from the EasySkyMesh Releases page
Follow the Flash custom firmware instructions for your specific board
If you want to add sensors to a repeater node, see the Add sensors to repeaters guide

Feature Suggestions

You can request specific features or ask for pre-built binaries for your board in the EasySkyMesh Discussions.

OTAFIX Bootloader (nRF52 Devices)¶

Adafruit_nRF52_Bootloader_OTAFIX is an enhanced bootloader for nRF52840-based MeshCore devices (RAK4631, Heltec T114, XIAO nRF52840, T1000-E, ProMicro NRF52840, and others). It fixes common OTA update issues and improves DFU reliability.

Supported Boards¶

Elecrow ThinkNode M1, M3, M6
Heltec Automation Mesh Node T114
LilyGO T-Echo
Nologo ProMicro NRF52840 (SuperMini NRF52840)
RAK 4631 / RAK WisMesh Tag
Seeed Studio T1000-E, SenseCAP Solar Node P1, Wio Tracker L1
Seeed Studio XIAO nRF52840 BLE / SENSE

Key Improvements Over Stock Bootloader¶

Defaults to OTA DFU mode when no valid application is present, preventing devices from getting stuck in UF2 mode after a failed OTA update
Maximum BLE TX power (+8 dBm on nRF52840) for improved OTA range and reliability
High-MTU BLE support for faster OTA transfers on Android and compatible hosts
Automatic reboot into the application after a successful OTA update over USB (no manual reset needed)
Board-specific BLE advertising names in DFU mode (e.g. RAK4631 advertises as 4631_DFU, ProMicro as PROM_DFU)

Installing the Bootloader¶

Erase required for MeshCore/Ripple firmware

If your device is currently running MeshCore companion firmware or Ripple firmware, you must run an erase after flashing the new bootloader. Use the MeshCore web flasher for this — it will guide you to the correct erase firmware. Other erase tools will not erase the ExtraFS area and will leave your device in a broken state.

Download the update-*.uf2 file for your board from the OTAFIX Releases page
Enter UF2 mode on your device by double-pressing the reset button within 0.5 seconds — your device should appear as a USB drive
Copy the UF2 file onto the mounted drive — the device will flash and reboot automatically

XIAO nRF52840 BLE variant check

Many XIAO boards ship with the Sense bootloader variant pre-installed. To check: enter UF2 mode, open INFO_UF2.TXT on the drive. If it shows Board-ID: nRF52840-SeeedXiaoSense-v1, install the SENSE variant of the OTAFIX bootloader, not the plain BLE variant.

Performing an OTA Update¶

Use the nRF Device Firmware Update app (Android / iOS) or nRF Connect (Android / iOS).

Recommended settings for OTAFIX 2.0+:

Setting	Value
Packet Receipt Notification (PRN)	ON
Number of packets	30
Reboot time	0 ms
Scan timeout	2000 ms
Request high MTU	ON for Android / not available on iOS
Disable resume	ON
Prepare object delay	0 ms
Force scanning	ON
Keep bond	OFF
External MCU DFU	OFF

OTA on a MeshCore repeater

Log into your repeater via the Remote Management CLI and run start ota first. Then open the nRF Device Firmware Update app, select the appropriate MeshCore firmware zip, and connect to your device (advertised as RAK4631_OTA, ProMicro_OTA, etc.).

OTA fails with 'Error: Operation Failed'

If the transfer fails early, try disabling Request High MTU and experiment with different PRN values (12, 8, 1, or off). Some Android BLE stacks don't handle high MTU well.

Device Not Appearing as USB Drive or Serial Port¶

After flashing OTAFIX 2.0+, if your device doesn't show up as a drive or serial port, it is likely waiting in OTA DFU mode (the default when no application is present). No UF2 drive or serial port is exposed in this state.

To exit OTA DFU mode and enter UF2/serial mode: double-press the reset button.