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README.md

     
 Several limitations apply to writing.  Only previously unwritten portions of the file may be written.  File sizes can never change.  Writes may only be done within the file's original size.
 
+### Erase Data
+
     file.erase();
     
-Only files created for erasing can be erased.  The entire file is erased to all 255 (0xFF) bytes.
+Only files created for erasing can be erased.  The entire file is erased to all 255 (0xFF) bytes, which allows the file to be written with new data.
     
 ## Managing Files