RX TX Communication

Using Arduino Programming Questions
#1

Hello,

I am trying to send sensor values collected with an Arduino Uno to another Arduino and then to the Computer. This second Arduino is necessary because of the build-up. So on the first I've got Serial.write() and on the second I've got Serial.write(Serial.read()). It works well, with the only issue that I get unreadable values in some weird notation.

Example: "HI" would be 727310.
Please help!!!

Thank you in advance

#2

Julek:
Example: "HI" would be 727310.
Please help!!!

Let me make a guess:
You are sending "HI" from the serial monitor and the serial monitor is configured to send "Newline" at the end of a line?

'H' is ASCII-72
'I' is ASCII-73
LF (line feed) is ASCII-10

All together is:727310

So what?

Perhaps loop up a thing called "ASCII table" to find out the ASCII codes of printable characters and control characters.

#3

Your problem is probably the code that finally prints out those values. This would reside on a computer somewhere? Running some code that has nothing to do with the arduino.

#4

@Jurs:
Thank you very much for your fast reply. I used this website: http://arduino.cc/en/Tutorial/ASCIITable. To adjust the values at the second Arduino I wrote this code:

void setup(){
Serial.begin(9600);
}
void loop() {
if (Serial.available() > 0) {
int v = Serial.read();
if(v>=48 && v<=57){
v = v - 48;
Serial.print(v);
}
else if(v==59){
Serial.print(";");
}
else if(v==64){
Serial.println();
}
else if(v==46){
Serial.print(".");
}
else if(v==45){
Serial.print("-");
}
}
}

It works perfectly.

Cheers!

#5

Julek:
@Jurs:
Thank you very much for your fast reply. I used this website: http://arduino.cc/en/Tutorial/ASCIITable. To adjust the values at the second Arduino I wrote this code:

But perhaps you not really wanted to write code for numerical ASCII-code processing, but you wanted to process characters instead of numerical values and send them back using 'write' instead of 'print'?

void loop() 
{
  if (Serial.available() > 0) 
  {
    char c = Serial.read();
    Serial.write(c);
  }
}
#6

In your first post you say you're using Serial.write then you post code that has Serial.print I suggest you do some research to understand the difference. This is where your problem lies.

#7