Print Byte Array in Serial monitor screen of Arduino IDE

Question

I need to print mentioned below byte array on the serial monitor screen of Arduino IDE

char b[]= {'0x7E', '0x00', '0x1C','0x90', '0x00', '0x13', '0XA2', '0x00', '0x41', '0x58', '0x1C', '0xCB', '0xFF', '0xFE', '0xC1', '0x7C', '0x00','0x0F', '0x00', '0x01', '0x00', '0x00', '0x37', '0x46', '0x46', '0x46', '0x00', '0x00', '0x00', '0xE7' };
void setup() {
Serial.begin(9600);
}

void loop() {
Serial.println(b[]);
delay(500);
}

But whenever I am trying a print, the error problem was there which was not resolved which is

C:\Users\Misha\Desktop\test\Test_2\Test_2.ino: In function 'void loop()':

Test_2:8:18: error: expected primary-expression before ']' token

 Serial.println(b[]);

                  ^

exit status 1
expected primary-expression before ']' token

Any suggestions on this will be great help.

Answer 1

You can’t print an array in that way.

If you want to print an array of hexadecimal value (with two digits), you have to use sprintf function and change declaration of b array.

uint8_t b[]= {0x7E, 0x00, 0x1C, 0x90, 0x00, 0x13, 0XA2, 0x00, 
              0x41, 0x58, 0x1C, 0xCB, 0xFF, 0xFE, 0xC1, 0x7C, 
              0x00, 0x0F, 0x00, 0x01, 0x00, 0x00, 0x37, 0x46, 
              0x46, 0x46, 0x00, 0x00, 0x00, 0xE7};
int i;

void printHex(uint8_t num) {
  char hexCar[2];

  sprintf(hexCar, "%02X", num);
  Serial.print(hexCar);
}

void setup() {
  Serial.begin(9600);
}

void loop() {
  for(i=0; i<sizeof(b); i++){
    printHex(b[i]);
 }

 Serial.println();
 delay(500);
}

The output produced is:

7E001C900013A20041581CCBFFFEC17C000F0001000037464646000000E7 7E001C900013A20041581CCBFFFEC17C000F0001000037464646000000E7 7E001C900013A20041581CCBFFFEC17C000F0001000037464646000000E7