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OpenFAN Micro firmware upgrade

OpenFAN Micro has an online firmware updater that is based on ESPHome Web.

You can use this tool from your browser to update any OpenFAN Micro to the latest firmware version.

Device Configuration

Due to how firmware upgrade works, currently it will not preserve any configuration data (ie. WiFi settings, Fans settings, device name etc).
After upgrading firmware, you will have to configure your device.

1. Preparing the hardware

In order to update firmware on your OpenFAN Micro you will need to put the device in the bootloader mode first.
To do this you will need to:

  1. Disconnect any FANs if connected to the board
  2. Press and hold BOOT button on your OpenFAN Micro
  3. Connect USB-C cable to OpenFAN Micro
  4. Note that only the power (RED) LED should be on.
  5. At this point your PC should register new Serial COM port

2. Loading new firmware

There are multiple ways to compile and load new firmware for OpenFAN Micro.
In order to make this process more convenient, latest version of the firmware can be loaded through web flasher tool.

To access the web flasher, you will need Google Chrome (or any other web browser that supports Web Serial API).

  1. Place OpenFAN Micro in bootloader mode (see step #1.)
  2. In Chrome open https://docs.sasakaranovic.com/esp32/openfan-micro/
  3. Click on Connect button
  4. From the drop down menu select the COM port that corresponds to your OpenFAN Micro and click Connect
  5. Click on Install OpenFAN Micro and then confirm by clicking on Install button
  6. Erasing and then flashing will start. This may take a minute or two
  7. After flashing is complete, you can disconnect OpenFAN Micro by removing USB-C cable
  8. Your OpenFAN Micro is now flashed to the latest firmware version

ESPHome Web!

This web flasher is using the Web Serial API, powered by ESPHome Web.