DIY Gradiometer Kit — WiFi Connection Fix
This procedure fixes WiFi connection issues on the MAG-BOARD used in the DIY Gradiometer Kit. It involves three phases: an initial factory flash, a firmware upload via Arduino IDE, and a final firmware flash.
Requirements:
- MAG-BOARD connected to PC via USB
- ESP32 Flash Download Tool
- Arduino IDE (free version)
factory_WROOM-32.binandmag_board_v1.32.binfiles from the.bindirectory- MAG-BOARD user software from the
mag-board_userdirectory
Phase 1 — Initial Flash
-
Connect the MAG-BOARD to your PC via USB.
-
Open the ESP32 Flash Download Tool.
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In the configuration window, select the following and click OK:
- ChipType: ESP32
- WorkMode: Develop
- LoadMode: UART
-
In the flash configuration panel:
- Check the first file slot and select
factory_WROOM-32.bin(located in the.bindirectory) - Set the flash address to
0x0 - Ensure DoNotChgBin is selected
- Check the first file slot and select
-
Select the correct COM port for your MAG-BOARD.
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Click START and wait until the panel shows FINISH.

Phase 2 — Arduino IDE Upload
After Phase 1 you will have valid firmware for WiFi connection, but Phase 2 and Phase 3 are still required to complete the fix.
- Open Arduino IDE.
- Upload the MAG-BOARD user software located in the
mag-board_userdirectory to the board.

Phase 3 — Secondary Flash
-
Re-open the ESP32 Flash Download Tool.
-
Update the flash configuration:
- Uncheck the
factory_WROOM-32.binfile slot - Check a file slot and select
mag_board_v1.32.bin - Set the flash address to
0x10000
- Uncheck the
-
Click START and wait until the panel shows FINISH.

The WiFi connection fix is now complete.
Troubleshooting
COM port not detected
- Check Device Manager for driver errors
- Install the CP210x or CH340 USB-to-UART bridge driver depending on your hardware revision
FINISH not shown / upload fails
- Verify the USB cable supports data transfer (not charge-only)
- Try a different USB port
- Restart the Flash Download Tool and retry from Phase 1