Good Morning Bert!
Zitat:
BTW: is there a way of knowing that the card is corrupted from the LEDs?
Yes and no... If the implementation of the file system FAT16 detects an error the red LED lights up (general fault detector).
But, well, while physical access failures detected with high reliability, it is for the file system only partly the case. The FAT16 library is kinda "spartan" of course, we're on a microcontroller with limited memory, ROM and RAM. So we do not really have a chance to detect each possible problem within the file system. Even a native OS wouldn't have a chance to.
On Windows, in a command shell: "chkdsk <drive>"
Do not let "chkdsk" repair the file system, re-format the SD: "format <drive>".
In severe cases, use the SD formatter:
https://www.sdcard.org/consumers/formatter_3The worst enemy of the file system is the operating voltage of the logger. Particularly problematic is the use of Greencaps in connection with a series resistance against the "Lightning".
The "LED show" is part of a 5-second hold loop at startup against "crazy voltage", waiting for that calmed the supply voltage.
Use the SD, once formatted, not in other devices such as cameras, for example.
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And btw: No need to copy the CONFIG.txt back to a reformatted SD "by hand". JLog remembers the last good configuration in his EEPROM (non-volatile memory) and will regenerate the file by itself.