Installing USB drivers on Windows

To use Viaflash with Windows, the appropriate driver must be installed.  Viaflash uses the WinUSB library to communicate with the module, using a firmware updating protocol built into the microcontroller called DFU.  Zadig is a Windows application that installs generic USB drivers that we will use to detect via and install the appropriate driver. 

1. Download and run Zadig. 

2. The Via should not be plugged into a power supply and the expander cable should be unplugged.  Next, push down and hold the "DFU" button while plugging in your via.  Once it's plugged in, you can let go of the button.

3. Click options/list all devices. 

4. If the module is in DFU mode, you should see "STM32 BOOTLOADER" appear in the drop-down list. 

5. Select it, and set "target driver" (to the right of the green arrow) to WinUSB. 

6. Click "Install Driver" and you're done!

7. If you get an error message, "Device descriptor request failed", try a different USB port on another USB controller if you have it.

8. If you are unable to install the correct driver, contact us.