-static const char ao_gps_set_nmea[] = "$PSRF100,0,57600,8,1,0*37\r\n";
+#undef AO_GPS_4800
+
+#ifdef AO_GPS_4800
+static const char ao_gps_set_nmea[] = "\r\n$PSRF100,0,57600,8,1,0*37\r\n\r\n";
+#else
+static const char ao_gps_set_nmea[] = "\r\n$PSRF100,0,4800,8,1,0*0F\r\n\r\n";
+#endif