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);
}