How to put firmware update on SD card? - PentaxForums.com
How to add files to the root directory of a USB - Quora
external sd - Suddenly most of the files and folders in my sd card are now named "FSCKxxxx.REN". How to fix this without root? - Android Enthusiasts Stack Exchange
SDcard: using to fill [data] objects · Issue #16 · electro-smith/oopsy · GitHub