What does this Error mean? (Bluetooth, Error 513)

So I am trying to send multiple x and y coordinates to my ESP32 while also displaying them in the chart..
I am having multiple issues with this one.
The good thing is, I can display the X and Y coordinates in the chart.
The bad thing is, they wont show up in the Serial Monitor on the ESP and I dont know why.
This is the Error Code i am recieving:

This is my App UI:

And my Code:

And the Code for my ESP32 on the Arduino:

I would be glad if u have any advice or if you know how to fix my issue! :slight_smile: tysm

You are sending s list of one sublist, which has 2 items.
Try to send the list with the 2 items directly


Tysm for your answer! :slight_smile:
Do you mean like that?

When I do that, i get this error message:

It only wants one number but you sent a list of two.

Use a different block or different input.

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Previously you used the SendBytes method, which accepts a list
Now you used the Send1ByteNumber method...
See also the documentation


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tysm <3

So, now Its possible for me to send the x and y coordinates to the ESP. They show up like this:
Is there a possible Way to name these coordinates (in the App)
for example, would it be possible that if i click the button, it would show up somewhat like this:


Or my question in general, can i somehow lable the data i am sending to the esp so that i can somehow code with them later on?
tysm :slight_smile:

As first list item add the text K1:

i did that, (like in the code below), but it somehow displayed the text in some random numbers, idk?
this is my MIT block code:
and this is my ESP code and what i recieved in the Serial Monitor:

So i am guessing, its some type of ascii? display, because you can clearly see the 11; 11 i typed in as before.

Do you have some advice on how to fix this? :slight_smile: tysm



I already tried that before, this was the error code i got so I assumed something was fishy:

I used the same ESP code as before and when i use this method, nothing shows up on the Serial Monitor.

this is the whole Code,

This is the "relevant" code, the one that causes me issues:

So what I am trying to do is, to "Label" the coordiantes i am sending so that i can use them in my code later on (because I am working with 3 coordiante pairs, i cannot only work with SerialBT.read)

Yes, sorr,y, you can use the SendBytes method only for a list of integers
If you want to send additionally some text, use the SendText method and join all information you like to send using the join block, you might want to add a delimiter of your choice, for example a comma


why would i need a delimiter, what do you mean by that?
is there something i should change in my ESP code or what do you mean?

Here are some samples to read ...

up to

thank you so much <3