LilyGo T3 S3 (SX1262)

⚠️ Check that radio.rxgain(on) and flood.advert.base (0.308) are set correctly after flashing! ⚠️

This build is based on official MeshCore 1.15.0 dev branch (as of 25-May-2026 and additionally includes the following unmerged upstream PRs/changes:

• PR2553: Limit flood advert packet forwarding --> set flood.advert.base 0...1 (0: no flood adv. forwarding, 0.308: default, 1: all flood adv. forwarding)
• PR1810: Allow direct message paths when denyf * is set
• :new: PR1727: Use hardware channel activity detection for checking interference --> Use set int.thresh 1 to activate hw based channel activity detection.
• :new: PR2377: Disable NRF52 undervoltage bootlock feature

Additional changes:

• Flood adverts are disabled (flood.advert.interval set to 0) by default
• :new: modified PR1810 to not block flood adverts but only PAYLOADTYPEGRPTXT and PAYLOADTYPEGRPDATA so that some limited flood advert distribution can be managed via PR2553 to support e.g. observer maps.

Changelog:

• Based on dev v1.15.0 as of 25-May-2026

Full Changelog: https://github.com/mattzzw/MeshCore-Evo/compare/v1.15.0-evo0.1.20...v1.15.0-evo0.1.21

Built for long off-road adventures and harsh winter conditions

• Based on MeshCore 1.17.1 mainline.
• Developed by IoTThinks and tested by our supportive MeshCore friends.
• Contribution to MeshCore: By IoTThinks%20is%3Apr%20author%3A%40IoTThinks).
• Source code: https://github.com/IoTThinks/MeshCore/tree/PowerSaving-v17
• With contributions from Dom4n and MeshCore friends

Notices:

16 Sep 2026: PowerSaving 17.1.5

• Disabled automatic light sleep for USB Companion on ESP32 for better serial connectivity.

15 Sep 2026: PowerSaving 17.1.4

• Imported a fix for RAK 3401 battery variant from MeshCore dev. If there is no GPS module, 5V power to the LoRa 1W will be floating and unable to provide maximum TX power as expected. Thanks Mr. Martenumberto for your discovery and persistence.
• Added BSEC for BME680 on RAK 3401

13 Sep 2026: PowerSaving 17.1.3

• (Repeater) RXPSv2: Better power consumption for "set radio.rxps balanced". You can now use "set radio.rxps max". All CLIs are at RXPS CLIs
• (Companion) RXPSv2 is enabled by default with powersaving on.
• (Repeater) Added support of button press for ESP32 repeaters with powersaving on
• (Repeater) Fixed crash if doing "gps" on ESP32 repeaters without GPS module
• (Companion) Moved uptime to below battery icon. Shifted dots left.
• (Repeaters and sensors) Added "If GPS on after powersaving on", telemetry request will trigger GPS update"
• (Sensors) Added MCU temperature
• (Sensor) Added PowerSaving for sensor firmware
• Added Tracker v2 and T-Deck
• Added heltec

trackerv2companionradiousbfemoff and heltectrackerv2companionradiousb_femon

Added board MKE-S3 (Vietnam)

10 Sep 2026: In case you can not see the "uptime" clearly in companions, please upgrade to PowerSaving 17.1.3 05 Sep 2026: You are advised to reboot repeaters / room servers after on/off or changing RXPS settings. Thanks Mr. Gordon for extensive testing.

Custom Development and Partnership

If you want custom development for your projects, Contact Us Looking for Partnership? Discuss Partnership

Support PowerSaving?

Support the development via  or . Buy boards with a coupon and help support ongoing development.

Instruction:

• Flash Custom Firmware as in INSTRUCTION. 👈
• Scroll down to bottom to download uf2 / upgrade.bin to upgrade or freshInstall-merged.bin for new devices. 👈
• Heltec v4 bin files is for both Heltec v4.2 and v4.3. Heltec v4.3 bin files is for Heltec v4.3 only
• Heltec v4.3 and T096 have two options FEM RXgain on and FEM Rxgain off.
• If for board build or support, please ask us at GITHUB or Discord

Quick Usage

Repeaters / Room servers

All PowerSaving features are disabled by default and persisted across reboots. PowerSaving: powersaving on, powersaving off and powersaving GPS PowerSaving: powersaving on then gps on and gps. RX PowerSaving: set radio.rxps balanced and get radio.rxps. Repeaters with RXPS enabled are less affected by noises from cell towers. It may due to LoRa RX only wakes up periodically. Added Battery voltage and PowerSaving status to repeater OLED Set dark theme for Heltec T096. For Heltec v4.3, 4.3R8, T096 and Tracker v2, you may set FEM off to save 10mA: set radio.fem.rxgain off

BLE / USB Companions

All PowerSaving features are enabled by default. GPS PowerSaving is enabled when you enable Position in MeshCore app. Added uptime for all companions. Set dark theme for Heltec T096.

• For Heltec v4.3, 4.3R8, T096 and Tracker v2, you may use femoff version to save 10mA.

Complete Guides in Wiki

Check the PowerSaving Wiki for more details:

• All the features
• All CLI commands
• How it works
• Test results

Enjoy MeshCore with PowerSaving. 👍

Based on MeshCore v1.14.1 plus the below features:

16 April 2026 -v14.1.1: Disabled NRF52POWERMANAGEMENT for RAK4631, RAK3401, Heltec T114, Xiao NRF52, Senscap Solar and Ga56230s meshkit and Ga56230s mesh tracker pro. 10 Arpril 2026 - v14.1.1: [BETA] Added Power saving for Heltec v3, v4.2 and v4.3 companion BLE. Reduced from 120mA down to 32mA for Heltec v3 and 39mA for Heltec v4. LNA and FEM LNA use default settings (E.g On). 09 April 2026 - v14.1.1: Fixed reset issue in high traffic locations for ESP32-based repeaters and room servers.

NEW FEATURES:

Added Heltec v4.3 support: https://github.com/meshcore-dev/MeshCore/pull/1867. The PR will automatically detect Heltec v4.2 and v4.3. Added CLI control to LoRa's FEM LNA: https://github.com/meshcore-dev/MeshCore/pull/2140. Heltec T090 is not included. The details are below. Added CLI "powerlog" to list the last reset reason, last shutdown reason (NRF52 only) and last boot voltage (NRF52 only). This is to help debugging why the boards were reset due to software fault or low voltage (brownout).

FEM LNA vs. Chip LNA:
FEM LNA is external LNA from the 1W boards (such as Heltec v4.3). You can on / off this FEM LNA: set/get radio.fem.rxgain on/off. This will impact the RX gain and power consumption (up to 7.8mA). When this is off, Heltec v4.3 can reach 5.8mA. For Heltec v4.2, this CLI will return "Not supported" as it does not support FEM control.
Chip LNA inside SX1262: This is available to all boards including 1W boards. You can on/off this LNA : set/get radio.rxgain on/off. This will impact the RX gain and power consumption (up to 0.5mA)

Repeaters and Room Servers:

Included latest PowerSaving and PowerSaving CLI (powersaving, powersaving on and powersaving off): 5.0mA for NRF52, 10mA for Heltec v3, 13mA for Heltec v4.2 and 5.5 mA for Heltec v4.3 (with FEM off). https://github.com/meshcore-dev/MeshCore/pull/1687

#### Companions:

[NRF52] PowerSaving by default. Reduced from 9mA down to 5.8mA. https://github.com/meshcore-dev/MeshCore/pull/2286
[BETA] [ESP32] PowerSaving by default for Heltec v3 and v4. Reduced from 120mA down to 32mA for Heltec v3 and 39mA for Heltec v4.2 and 4.3.

Common features

Included sensor CLI to list I2C and UART GPIOs: sensor Kept date after crash/watchdog/brownout reset on ESP32: https://github.com/meshcore-dev/MeshCore/pull/1896 Automatically selected I2C address 0x76 and 0x77 for BME280/BME680/BMP280 Added i2c probe for sensors to start only in-use sensors: https://github.com/meshcore-dev/MeshCore/pull/1282 Added variant Xiao S3 (non-Wio) and Wio SX1262 (Initial support): SDA=D6, SCL=D7

Instruction:

Please upgrade your easy to access devices first. Download: Download upgrade.bin to upgrade existing devices or freshInstall-merged.bin for new devices. Instruction to Flash Custom Firmware. Please read the instruction in Add sensors to repeaters Source code for PowerSaving 14

Demo

Power Saving

Enter powersaving mode (CLI > powersaving on), 5.5mA for Heltec v4.3 with FEM and rxgain off, 5.8mA if FEM off and rxgain on. Thanks Wireless Rocks for your testing, . 13mA for Heltec v4.2 or Heltec V4.3 with FEM and rxgain on. 5.0mA for RAK4631

<img height="384" alt="image" src="https://github.com/user-attachments/assets/be6e298d-4931-4e83-8220-0d072f8aeefd" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/924aa3a5-64d0-4112-aa66-6ff72178d3ac" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/903d899d-66c4-4d88-bf61-e9601797009f" />

Default PowerSaving for Heltec v3, v4.2 and v4.3 companion BLE. Reduced from 120mA down to 32mA for Heltec v3 and 39mA for Heltec v4.
<img height="384" alt="image" src="https://github.com/user-attachments/assets/73689821-61cc-4c3e-833f-1511632b71df" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/f9161bf7-8a95-4e7d-b26a-7a6cbe88a615" />

PowerLog CLI

Enter CLI "powerlog" to see last reset/shutdown reason and the battery voltage during last boot. <img height="384" alt="image" src="https://github.com/user-attachments/assets/79a31bf6-a0c2-46d3-bf7e-d63ca27e3014" /> <img height="384" alt="image" src="https://github.com/user-attachments/assets/1870c4e7-5942-466e-af0c-66e7567c7aae" />

Sensor CLI

Enter CLI "sensor" to check I2C and GPS Serial pins <img height="384" alt="image" src="https://github.com/user-attachments/assets/060dd847-5984-4dc2-a5fe-cfe81180dc6c" /> <img height="384" alt="image" src="https://github.com/user-attachments/assets/49f25de7-a122-480f-a54a-a7176ec25f26" />

Support and Discussion

If you want us to compile for your boards or have question, please comment in GITHUB or DISCORD

Love the build?

• You may buy us a cofee ☕ for good work via Paypal  or Github .

We can buy more test boards and test sensors for development. Enjoy MeshCore. 👯‍♂️

Full Changelog: https://github.com/MichTronics/MeshCoreNG/compare/bridge-tcp-v1.0.5...repeater-v1.0.1

Full Changelog: https://github.com/MichTronics/MeshCoreNG/compare/bridge-tcp-v1.0.5...companion-v1.0.1

Full Changelog: https://github.com/MichTronics/MeshCoreNG/compare/bridge-tcp-v1.0.5...companion-v1.0.1

Full Changelog: https://github.com/MichTronics/MeshCoreNG/compare/bridge-tcp-v1.0.5...room-server-v1.0.1