About Arrays in Arduino

Question

I have a question about arrays in Arduino. Sorry for my bad English. I want to put numbers in an array, and I think the code below works properly.

However, it doesn't work and corrupted numbers show up in the Serial monitor. Even delay(1000) doesn't work.

If I change ND_MAC[i]=128; to "ND_MAC[i]=126;", it works properly. So I'm wondering if this array is char type, but I designate int to array. How to solve it?

int ND_MAC[7];
char i=0;
void setup() {
 Serial.begin(9600);
}
void loop() {
 for(i=0;i<8;i++){
 ND_MAC[i]=128;
 Serial.print(ND_MAC[i],HEX);
 }
 Serial.println();
 delay(1000);
}

• Mikael Patel: First error is iterating outside the array. ND_MAC has 7 elements (0..6).

Answer 1

For an array of size 7, the indexes start from 0 (ND_MAC[0]) and end at 6 (ND_MAC[6]) as @MikaelPatel commented.

So the solution to your issue would be changing the condition in for loop to

for(i=0;i<7;i++) //Changed 8 in your code to 7

Here, the loop iterates from i = 0 to 1 < 7 (i.e., till 6) and it should work. :)

• kishida: Oh,I had a terrible mistake...
• kishida: Oh,I had a terrible mistake... I followed your help, and then it worked properly. thank you very much!
• Prashanth Benny: @kishida you're welcome....