ext_Flash_write_sample erase sector optimization: The previous function erased a sector while writing sample data causing a delay of up to 200ms. The new implementation checks at the end of a write sample call if we are close to a sector end. In case we are a erase sector command will be send to the flash for the next sector. At the time of the next sample write (2 seconds later) the next sector is already erased and no busy wait of 200ms is needed => max write time for samples is not less than 5ms.

1b9be6040d8279117c7fc99d528790611638f10b V1.4.7 release
ba9d99a2e310da601a948ff11ad665260c600e18 v1.4.8 release
143fe85f82a2e2aca50eb0c29bc55066cb4fe497 v1.5.0 release
afa55a50cc724b11b959fa81567d59ede251ef22 v1.5.1 release
54a480c43e977db8fc6969551ad6148f2ad46e15 v1.5.2.beta release