Quick Spark test app for sending binary to a Spark.function

binary-to-serial.ino

int binaryToSerial(String s) {
  int len = s.length();
  for (int i=0; i < len; i++) {
    Serial.write(s[i]);
    Serial.write(' ');
    Serial.println(s[i], HEX);
  }
  return len;
}

void setup() {
  Serial.begin(115200);
  Spark.function("binary", binaryToSerial);
}