Device Firmware Upgrade
To upgrade the firmware of the STM32 microcontroller on your Snickerdoodle, please consult
Additionally, we'll provide a few tips here.
No LED's in DFU mode
The LED pattern seen when booting in to DFU mode varies depending on the version of the firmware booted. Some of the earliest firmware versions do not light the LED's at all.
Various pages suggest that you hold down the Reset button and the Select button together when booting to enter DFU mode. This works for nearly all versions of the firmware, but some pages suggest that this be done for three seconds, others say four or more seconds. This might lead to some confusion.
If your Snickerdoodle is connected to a Win10 machine, you should be able to release those buttons as soon the Windows 10 machine emits the sound that indicates that a USB device has just been plugged in. For most versions of the firmware, that will also be when you see the LED's on the Snickerdoodle flash.
Win10 DfuSeDemo can not find the Snickerdoodle
If you follow the steps in the Firmware User Guide, yet the DfuSeDemo window does not seem to find the Snickerdoodle STM32, you probably need to take some additional steps.
First open up Window's Device Manager. You should see the "Other Devices : STMicroelectronics Virtual COM port (COMxxxx)" or "Universal Serial Bus controllers : STM Device in DFU Mode" device active. If you instead see "STM32 BOOTLOADER" or even "STM32 BOOTLOADER" with a caution symbol, you might not have proper device drivers installed on Windows.
The documentation for the DFU package indicates that one needs to install the proper device driver after doing the initial install.
Assuming that you have installed DfuSe, you probably have a DfuSe installation directory at a location like "C:\Program Files (x86)\STMicroelectronics\Software\DfuSe v3.0.6" , and the directory tree below it probably contains the device driver you need as well as a .exe file to help you install the driver.
To find that .exe look in the Bin/Driver directory below the installation directory you found above. Here you should see some directory names like "Win7", "Win8", "Win8.1", and "Win10". Double click on the appropriate one for your installation of Windows.
In this subdirectory you should see two .exe files that should help with the installation of the device driver. One (ex. "dspinst_amd64.exe") installs the 64 bit driver whereas the other (ex. "dpinst_x86.exe") installs the 32 bit driver. Invoke the appropriate one. It should lead you through the device driver installation process.
After completing this, restart DfeSEDemo.