Flash the latest Azimuth firmware to your Heltec WiFi LoRa 32 V4 directly from your browser using Web Serial. No Arduino IDE required.
USB JTAG/serial debug unit or CP210x port. On Windows it appears as a COM port.If you've modified the firmware source code, you'll need to compile and upload your own binaries. Here's how to build and release them for use with this flasher.
Step 1 — Set up Arduino IDE
Install Arduino IDE 2.x. Add the Heltec ESP32 board package via File → Preferences → Additional Board Manager URLs: https://github.com/Heltec-Aaron-Lee/WiFi_Kit_series/releases/download/0.0.9/package_heltec_esp32_index.json
Step 2 — Configure board settings
| Setting | Value |
|---|---|
| Board | WiFi LoRa 32(V4) |
| USB CDC On Boot | Enabled |
| Partition Scheme | 16M Flash (3MB APP/9.9MB FATFS) |
| Flash Mode | DIO 80MHz |
| Flash Size | 16MB |
| Upload Speed | 921600 |
Step 3 — Export compiled binary
In Arduino IDE go to Sketch → Export Compiled Binary. This creates three files in the sketch folder:
| File | Flash address | Description |
|---|---|---|
| bootloader.bin | 0x0000 | ESP32 bootloader |
| partitions.bin | 0x8000 | Partition table |
| firmware.bin | 0x10000 | Azimuth application |
Step 4 — Create a GitHub Release
Push your changes to the main branch on GitHub. Then go to Releases → Create a new release. Tag it as v3.x.x following semantic versioning. Upload the three .bin files as release assets. Mark it as Latest release when it's ready.
Step 5 — Test before publishing
Flash a device using the pre-release tag first. Only mark a release as Latest once you've confirmed it boots correctly, connects over BLE and the GPS initialises.
A note on licensing: The Azimuth firmware is released under the MIT License. This means anyone can use, modify and distribute it — including commercially — as long as the original copyright notice is retained. If you distribute a modified version, you must keep the LICENSE file in your repository. You do not have to open-source your changes, but you're encouraged to contribute them back.