How to convert a delimited string of hex numbers to an int array

Question

I am sending a string to the Arduino via serial, I made the program that sends the data, so I can change it to anything, but for now it sends a string of hex numbers delimited by ':', so for example 00:AA:FF and I need to get that into an int array onto the Arduino, the main problem is I don't always know how big the array will be, sometimes just 2 indexes, other times 16 indexes.

As I said, I made the program sending the data so I can make the data anything, I just need to get an int array to the Arduino and get it back as an int array via serial

• jsotola: is this a school assignment?
• Majenko: Do you know an upper limit on how many there will be?

Answer 1

You could store the hex numbers in a int array using strtok() and strtol().

char str[] = "00:AA:FF:7FFF";
int intArray[16]; // Maximum number of hex numbers.
void setup(){
 Serial.begin(9600);
 int counter = 0;
 char * pch = strtok(str, ":");
 while(pch != NULL){
 intArray[counter] = strtol(pch, NULL, 16);
 pch = strtok(NULL, ":");
 counter++;
 }
 Serial.print("Item Count = ");
 Serial.println(counter);
 for(int i = 0; i < counter; i++){
 Serial.println(intArray[i]);
 }
}
void loop(){}