Combinging multiple numbers into a string

Projects Programming
1

Hi! I'm pretty much a novice at coding in general, and I need some help. I'm trying to transmit a set of three numbers all at once via serial.write. the first two are analog input readings, so a number between 0000 and 1023, and the third is a decimal representation of a binary number. The program receiving this number has a pretty simple function for splitting variables into pieces, so I could send a number like 0034095323 and it could easily split that into 0034, 0953, and 23, I just can't figure out how to combine them on the arduino. The three numbers are currently stored individually in three variables.

I think it has something to do with strings, but I can't figure it out. I would appreciate some help with this. Thanks!

2

keboose:
...it could easily split that...

Just don't split the number. Why do you do it?

3

it's the program on my PC that can split the number. I want to transmit all three numbers at once from the arduino, so I am looking for a way to combine them all into one variable to send over the serial connection.

4

With Serial.write(), as you can read in this page, can't send int variables directly, so you need to convert it into a string.
So, 3 numbers of 4 digits each = 12 chars + 1 NULL TERMINATOR, you have a string of fixed length 13.
Using the itoa() function, you can convert an int into string.

Start with this code:

char DataToSend[13];
char SingleInt[5];

int Number0 = 123;
int Number1 = 567;
int Number2 = 8901;

void setup() {
  Serial.begin(115200);
  
  memset(DataToSend,0,sizeof(DataToSend)); //Ensure it's empty.
  itoa(Number0,SingleInt,10);
  strcat(DataToSend,SingleInt);
  itoa(Number1,SingleInt,10);
  strcat(DataToSend,SingleInt);
  itoa(Number2,SingleInt,10);
  strcat(DataToSend,SingleInt);
  
  Serial.println(DataToSend);
  //Serial.write(DataToSend); This will send the info
}

void loop() {
  // put your main code here, to run repeatedly:

}
5

Thank you for the help. I'll give it a try and see if it works out.