stringsignal=2;// GNSS signal: "1C" for GPS L1 C/A, "1B" for Galileo E1b/c, "1G" for Glonass L1 C/A, "2S" for GPS L2 L2C(M), "2G" for Glonass L2 C/A, "L5" for GPS L5, "5X" for Galileo E5a, and "E6" for Galileo E6B.
stringnav_message=5;// for Galileo I/NAV: decoded half page (even or odd), 120 bits, as described in OS SIS ICD 2.0, paragraph 4.3.2.3. I/NAV Page Part.
// for Galileo F/NAV: decoded word, 244 bits, as described in OS SIS ICD 2.0, paragraph 4.2.2. F/NAV Page Layout.
// for Galileo HAS: decoded full HAS message (header + body), variable length, as described in Galileo HAS SIS ICD.