Hello! I'm working on a datalogger (using Arduino MEGA) for a few measurements for my master of science thesis. The logger has 12 soil humidity sensors, one sensor for relative humidity and temperature, two fans, and LCD that automatically showcases the current measurements in a certain order as a …

No, we actually need to see the hidden code. Please read the forum intro...

[image] cateto: The error messages never appear. I can't understand what I'm doing wrong, Me too. What type of help do you expect?

[image] How to recognize that an SD card has been removed or inserted? Storage SD cards must be reinitialized if you remove power. If you remove an SD card while the file system is being updated you can cause a corrupt file system. Newer SD cards buffer data in RAM so you…

Sorry, I haven't used a forum in a few years :sweat_smile: it should be readable by now

This is good, but I know when to remove the SD as not to corrupt the file. The LED on pin 13 lights up when the file is being written and turns off as the system waits. During that waiting time the file is closed, so it's not getting corrupted.

I'd suggest you start by commenting out large chunks of the program to see if you can find where the problem lies.

I've not used the SD card library very much but I seem to recall from various forum posts that it's not a good idea to keep opening and closing the file you want to write to. I think the general advice is to open the file during setup and then leave it open.

Thank you, I might try that. My only concern is that if the power goes out for some reason, the file is inevitably lost since it never closes except when you intend to take the sd out. So I'll think about it. Thank you!

I found NotePad++ opens those files without an issue. So far.

[image] cateto: the file is inevitably lost since it never closes If that were true, it would be a serious problem and everyone would know about it, but they don't, so I'm betting it isn't. I'm also betting you will have far more grief with files full of junk if you refuse to follow the advic…

Soil humidity datalogger

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Idahowalker March 30, 2023, 2:16pm 4

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Soil humidity datalogger

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