Low memory available, stability problems.CODE OUTPUT BAD

HI !!!
I’m using Arduino UNO wifi dev edition board
running some codes for a school project
have this error when I compile and upload any advice on how to go about this?
really appreciate the help in urgent need of help :frowning:

testing.ino (3.77 KB)

If possible you should always post code directly in the forum thread as text using code tags (</> button on the toolbar). This will make it easy for anyone to look at it, which will increase the likelihood of you getting help. If the sketch is longer than the forum will allow then it’s ok to add it as an attachment but in this case it is not too long.

mmmarakar:
have this error when I compile and upload

That’s not an error, it’s a warning. It’s very important to understand the difference.

mmmarakar:
any advice on how to go about this?

Everywhere you have something like this:

Serial.println("NiSense System Active");

do this:

Serial.println(F("NiSense System Active"));

That moves the string literals from the dynamic memory you’re running short of to program memory.

Don’t use String. It uses a lot of memory and may cause your code to be unreliable due to memory fragmentation. Use strings (null terminated char arrays) instead:
https://www.arduino.cc/reference/en/language/variables/data-types/string/
http://www.cplusplus.com/reference/cstring/