Assignment to constant variable.

[djiworks]

// For each octet
  for (let i = 0; i < numOctets; i++) {
    // Ready as hex string
    let str = data.readUInt8(i).toString(16); // use let instead of const because its value can change depending on length
    // If it's only 1 byte, add 0 to front
    if (str.length == 1) str = '0' + str;
    // Put in array
    bytes.push(str);
  }