example of printing binary data in Arduino

gistfile1.txt

source: https://github.com/earlephilhower/ESP8266Audio/blob/2f2898c49612f1cc1351b44ffe8541def5a26b23/src/AudioGeneratorMIDI.cpp#L71

void AudioGeneratorMIDI::midi_error(const char *msg, int curpos)
{
  cb.st(curpos, msg);
#if 0
  int ptr;
  Serial.printf("---> MIDI file error at position %04X (%d): %s\n", (uint16_t) curpos, (uint16_t) curpos, msg);
  /* print some bytes surrounding the error */
  ptr = curpos - 16;
  if (ptr < 0) ptr = 0;
  buffer.seek( buffer.data, ptr );
  for (int i = 0; i < 32; i++) {
    char c;
    buffer.read (buffer.data, &c, 1);
    Serial.printf((ptr + i) == curpos ? " [%02X]  " : "%02X ", (int) c & 0xff);
  }
  Serial.printf("\n");
#endif
  running = false;
}