Go Down

Topic: Serial.read crazy results (Read 10570 times) previous topic - next topic


Hello everyone,

I'm getting this problem that's driving me crazy, tried everything and googled for hours, now my last hope is this forum.

Here is the code:

int incomingByte = 0;   // for incoming serial data

void setup() {
        Serial.begin(9600);     // opens serial port, sets data rate to 9600 bps

void loop() {

        // send data only when you receive data:
  while ( Serial.available( ) > 0 ) {

                incomingByte = Serial.read();
                // say what you got:
                Serial.print("I received: ");


When I enter an integer, I should get it back right?

Here is what I get when I enter "4" instead:

Serial monitor:

I received: 52
I received: 10

Here is "0":

Serial monitor:

I received: 48
I received: 10

What am I missing?

Please advise



You're missing the difference between the ASCII representation of a digit, and the digit itself.
Comes up about once a month here.


I get that one, but it doesn't explain the systematic second line = 10.
It is the ASCII symbol for a new line and I don't know how to get rid of it.

Any ideas?


You are going to get ASCII representation codes on Key stroke inputs , You will understand more on reading about ASCII values on respective Key Strokes, Google for it.
"Real Men can Accomplish  Anything"

- skype : nishants5  
ਫ਼ਤੇਹ ਕਰੁਂ!


Carriage return / line feed,
13 / 10




Use something different to input your data, that doesn't send CR/LF.


thanks for your answer dxw00d, but man I'ma Newb :D

what you wrote is like chinese to me. could you please explain further? I'd be grateful to you



How are you entering your "4"? Are you using the serial monitor?


Maybe you can try Serial.write for incomingByte, and use if instead of while if you only need 1 byte. I might try it later.


There are two drop-downs at the bottom of the serial monitor. One of them selects what is sent at the end of whatever you type. It might say 'Newline', or 'Carriage return' currently. Try changing it to 'No line ending'.

If that doesn't work, you'll need a different terminal program.


Works great! with: 'No line ending'

but now it reads only one digit. So if I type 10, I get :

I received: 1
I received: 0

what should I change?

PS: Thanks dxw00d :)


Why not read the terminator....and ignore it?

Go Up