User's Manual

21
3.2.2 UDP Data
GPS UDP data: 512 bytes
Field
Bytes
Description
GPS time data
18
Header
2 bytes
0xFFEE, 0xFF first
Date
6 bytes
Year, month, and day (2 bytes each, lower byte first) in ASCII
Time
6 bytes
Second, minute, and hour (2 bytes each, lower byte first) in ASCII
μs Time
4 bytes
In units of μs (lower byte first)
GPRMC/GPGGA data
84
ASCII code, valid till 2 bytes after ‘*’
NMEA sentence that contains the date and time information
Users can select either GPRMC or GPGGA in the Settings page of web control, as shown in Section 4.2
reserved
404
404 bytes of 0xDF
GPS positioning status
1
ASCII code, obtained from $GPRMC or $GPGGA
When $GPRMC is selected:
When $GPGGA is selected:
A (hex = 41) for Valid Position
V (hex = 56) for Invalid Position
NUL (hex = 0) for GPS being unlocked
0 = invalid
1 = GPS fix (SPS)
2 = DGPS fix
3 = PPS fix
6 = estimated (dead reckoning)
flag of PPS lock
1
1 – locked 0 – unlocked
reserved
4
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