[Solved] What is the character encoding of Arduino's Serial messages?

Projects Interfacing w/ Software on the Computer
1

Hello :slight_smile:

I have a little problem, I'm writing a .NET program that is basically a serial monitor.

In the Arduino IDE's Serial monitor, message sent from Arduino, such as "Commande reçue", appear correctly.

But in my program, the "ç" is not displayed and shows a "?" instead -> "Commande re?ue".

I am wondering, what is the serial message encoded to, and how can I do to display it correctly in my program.

Here is how I read from the serial port, and fill a textBox with the message:

String^ input = this->serialPort1->ReadExisting();
this->textBox2->AppendText( input );

If I try something like this:

String^ input = "ç \u00e7";
this->textBox2->AppendText( input );

Then what I see in the textBox is: "ç ç"

I'm lost :frowning:

Ps: I'm beginner in writing Windows Form programs so please help me fix the problem, thanks :slight_smile:

2

In this link, the encoding is ASCII. http://arduino.cc/en/Tutorial/SerialCallResponseASCII

3

The encoding from the Arduino is raw - ie whatever you send. There's no BOF characters or anything like that sent before a serial transmission.

4

When I compile the app using your character, I get the following message;

"debug.ino" contains unrecognized characters.If this code was created with an older version of Processing,you may need to use Tools -> Fix Encoding & Reload to updatethe sketch to use UTF-8 encoding. If not, you may need todelete the bad characters to get rid of this warning

You may need to do as it suggests to get it to work.

5

You can use Serial.write() and send raw hex code out.
How the other end interprets the code will determine what is displayed.

For example, if you do this:

for (x=0x48; x<128; x=x+1){
Serial.write(x);
delay(250);
}

you will see
0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZavcdefghijklmnopqrstuvwxyz
and some punctuation marks because the serial monitor recognizes the ASCII codes.

6

To confirm: it's UTF8 encoding. when you type \u00e7 you are specifiying a unicode character using 2 bytes (00 and e7).

That's why you see 2 characters "Then what I see in the textBox is: "ç ç"" as the textbox is not unicode capable / enabled.

7

aarondc:
That's why you see 2 characters "Then what I see in the textBox is: "ç ç"" as the textbox is not unicode capable / enabled.

Actually the "\u00e7" shows as a "ç" in the textBox, which is correct

aarondc:
When I compile the app using your character, I get the following message;

"debug.ino" contains unrecognized characters.If this code was created with an older version of Processing,you may need to use Tools -> Fix Encoding & Reload to updatethe sketch to use UTF-8 encoding. If not, you may need todelete the bad characters to get rid of this warning

You may need to do as it suggests to get it to work.

I don't have this message, also I tried before, the Fix Encoding thing, but it only resulted in the Arduino IDE's Serial Monitor displaying "Commande reçue".

I tried

this->serialPort1->Encoding = Encoding::UTF8;

I tried every possible encodings for this setting, and also many other things like encode the input to another encoding... I can't get it working :frowning:

8

In the Arduino IDE's Serial monitor, message sent from Arduino, such as "Commande reçue", appear correctly.

But in my program, the "ç" is not displayed and shows a "?" instead -> "Commande re?ue".

It tell you Sun's Java supports unicode better than Microsoft's .Net. It is true since day one.

use RichTextBox, instead of textBox.

9

sonnyyu:
use RichTextBox, instead of textBox.

Same result with a richTextbox, also tried with different fonts as suggested... :frowning:

Edit: Solved :smiley: ! But I'm not sure it's the correct way to do it:

this->serialPort1->Encoding = Encoding::Default;

(working with both richTextBox and textBox )

10

I believe that the problem is in SerialPort.
Try to play with SerialPort.Encoding Property

Edit: I see that you resolved during my typing.

11

zoomx:
I believe that the problem is in SerialPort.
Try to play with SerialPort.Encoding Property
SerialPort.Encoding Property (System.IO.Ports) | Microsoft Learn
Encoding Classe (System.Text) | Microsoft Learn

Edit: I see that you resolved during my typing.

Desole. Je ne parle pas Italian :wink:

12

Yeah I tried previously every Encoding, BUT Default (I didn't know it was an encoding type), I thought it wouldn't change anything, but in fact that was the (or, one) solution!

Thanks all anyway for trying to help me :slight_smile:

13

aarondc:
Desole. Je ne parle pas Italian :wink:

Funny, the pages are in english for me but I noticed that all around is in italian because I used "Original" instead the tranlation.
These are in british english but you can change the language in the right top of the page.
SerialPort.Encoding Property (System.IO.Ports) | Microsoft Learn.
Encoding Class (System.Text) | Microsoft Learn