If your current firmware is 64 bit (this is how the MinnowBoard ships)fs0: .\MinnowBoard.MAX.FirmwareUpdateX64.efi _filename_.bin
If your current firmware is 32 bit (if you have already modified the original firmware to be 32 bit)fs0: .\MinnowBoard.MAX.FirmwareUpdateIA32.efi _filename_.bin
e.g.Shell> fs0: fs0:\> .\MinnowBoard.MAX.FirmwareUpdateIA32.efi MinnowBoard.MAX.I32.079.R01.bin
You might wonder why you need to invoke 'MinnowBoard.MAX.FirmwareUpdateX64.efi' even if we're only supporting a 32 bit version of Windows 10 IoT Core. The board usually comes with 64-bit firmware pre-installed on it. The bitness of the EFI has to match the bitness of the current firmware. Additionally, the bitness of the bin file has to match the desired bitness of the firmware after updating. So the first time you will likely need to use 64-bit EFI and 32-bit BIN. The second time and every other time you need to use 32-bit EFI and 32-bit BIN. The reason the bitness of the firmware has to match the bitness of the OS is that there is an EFI in the OS image that gets loaded to bootstrap the OS, and that EFI has to be the same bitness as the firmware as well.
The tool will enumerate devices as shown. Select the SD card you want to flash, and then provide the location of the ffu to flash the image.
NOTE: IoTCoreImageHelper.exe is the recommended tool to flash the SD card. However, instructions are available for using DISM command line tool directly.
Safely remove your USB SD card reader by clicking on "Safely Remove Hardware" in your task tray, or by finding the USB device in File Explorer, right clicking, and choosing "Eject". Failing to do this can cause corruption of the image.
NOTE: If you want to remove Windows 10 IoT Core from your SD card after you are done using it, see the FAQ section titled "How do I remove Windows 10 IoT Core from my SD card?".
If you have loaded a previous version of IoT Core on your MBM you will need to go through the following steps for your first boot (make sure you have your SD card with IoT Core inserted):
Supported Peripheral Interfaces and Devices