Custom teensy firmware to have the teensy act as a USB Mass Storage Device.
This is a learning project and the goal was to create a USB MSD with a Teensy 3.2 and the Micro SD card reader. While the code relies on existing Teensy and Arduino code, most of the dependencies have been removed and the USB driver updated/rewritten. As such it is a standalone project which only needs the gcc arm-none-eabi build tools to make and PaulStoffregen/teensy_loader_cli to load onto the Teensy.
Kevin Cuzner provided excellent information in his Teensy 3.1 Bare Metal Post and sample code at kcuzner/teensy-oscilloscope.
The final device is a Teensy 3.2 soldered together with a Micro SD Card Adapter, and a Micro SD card for storage. It provides logging over the first serial tx pin, and has been rudementarly tested with Linux v4.4.x and Windows 7.
Code Dependencies