I'm having trouble loading the VFS onto my custom board using a nrf52832. The board is not using an SD card and the only connections are UART lines (Rx and Tx) and 2 LEDs.

Within a Virtual Machine on windows I'm running Linux and have completed the following steps:

• I've altered the UART and LED pins in the micropython/ports/nrf/boards/pca10040/mpconfigboard.h to match my configuration
• I've set MICROPY_VFS in mpconfigport.h
• I've compiled using make BOARD=pca10040 MICROPY_VFS_FAT=1, this compiles successfully and generates the following hex
  

On windows

• On command line I can run the command "ampy -p COM9 run blink.py" which just blinks the on board LEDs
  However when I run the command
  "ampy -p COM9 ls"
  It just returns with nothing and the command line prompt appears. This leads me to believe that the VFS has not been installed correctly on the nrf chip.

I am able to open a python terminal via PuTTY and when I type the command "os.listdir()" it returns empty

Have I missed a step when compiling perhaps?
Any help would be greatly appreciated