Random shreds of texts in serial monitor

TFFF:no conn:no connno conno conn connconnonnnnnF:S2GND:S2GNDS2GND2GNDGNDNDDF:S2VCC:S2VCCS2VCC2VCCVCCCCCE!!rlaeelaee

That's what my serial output looks like on my project. looks like memory leak or something.
My sketch uses 66% of program memory, and global variables use 45%... so i have some left. It happen on both may arduino boards, so it's not a harware issue. The program itself seem to work properly, but the serial output is mess.
Those shreds of text in the output are fragments of all kind of debug texts I have all over the program. This output appears after start/restart arduino, before turning all the calculations, when no new variables are declared and used. just the global ones.
I noticed that every time the "random text" is the same.
what can it be?

Wrong Baudrate.

I knew about this, so I double checked the baudrate. It's set the same.

And those fragments appear in radom spans. sometimes one leter a second, sometimes twice a secons. sometime a letter sometimes few letters.
And the program is idle... it doesn't do anything after start. there should be no messeges.

Hi! Welcome to the Forum!

Well, given the Baud Rate is not the problem, it would be interesting to know something more about your code and hardware setup.

It seems to me that some "GND" and "VCC" appearances on your Serial Monitor are too much of a coicidence to be only garbage.

Are you receiving data from another device (like Bluetooth for example)?

Since this is your first post, take some time to read this topic:

How to get the best out of this forum

You´ll find useful tips on how to provide information that will be helpful to all other users.

Have fun! :upside_down_face:

In theese shreds are random strings that go after "Serial.print" or "Serial.println" from all over the program. Those VCC and GND are my error messegaes that they can't be shown at the moment. Like other fragments. The program doesn't do anything at the moment and those shreds appear form all over the code.
There are hundrets line of code, and all worked well... before.

I have MAX31855K thermocouple module connected. But when disconnected the mess still flow.

Time to show your code I think.

The faulty code that you forgot to post. Don't forget to use code tags!

Are you attempting to store the text in program memory, but reading it back from ram?

Something wrong with the code you forgot to show us...

Some possible reasons:

  1. Incorrect use of String objects and hence memory fragmentation
  2. Printing non-terminated c-strings and hence printing till the first terminator is found.

FYI, not knowing what it's supposed to look like, it looks absolutely normal to me :rofl:

Hi.
I wasn't at the computer during the weekend.
I found the bud and it was trivial. I had a Serial.print(something) dug in the code with a parameter with a value that was beyond its range and that's why it showed me some random stuff from memory.
Sorry for bothering you.

If you posted your code to start with, we could of had a resolution in the first reply!

Happy you got it working.

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There is too much code to paste here. I would not dare to bother you all to go through this.

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