A、NONE/NMEA B、NMEA/NMEA4800 C、GRMN/GRMN D、RTCM/NMEA
A、RX-LEVELFULL B、RX-QUALFULL C、RX-LEVELSUB D、RX-QUALSUB
A、PHYSICAL INFOMATION B、HANDOVER DETECTION C、HANDOVER COMMAND D、HANDOVER COMPLETE