NOTE: This was originally developed on Teensy 3.2 procesors. Back then I didn't realize that Teensys do the FILE_WRITE thing differently. So, until just lately, I had no idea that this wouldn't work on standard Arduinos. I found out, this has been fixed. Sorry about all that. -jim lee
Can this help you? Read the book and find out : https://github.com/leftCoast/LC_libraryDocs/blob/main/LC_libraries.pdf