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ZY-12 GPS Receiver
The structure of the MBEN message in binary format is shown below:
$PASHR,MPC,<Satellite Measurment Data + Checksum>
Table 4.3.
MBEN Message Structure [Binary Format]
Binary Type
Size
Contents
unsigned short
2
sequence tag (unit: 50 ms)
modulo 30 minutes
unsigned character
1
number of remaining struct to be sent for current
epoch.
unsigned character
1
satellite PRN number.
unsigned character
1
satellite elevation angle (degree).
unsigned character
1
satellite azimuth angle (two degree increments).
unsigned character
1
channel ID (1 - 12).
C/A code data block 29 bytes
unsigned character
1
Warning flag
unsigned character
1
Indicates quality of the position measurement. (good/
bad)
character
1
(set to 5 for backward compatibility)
unsigned char
1
Signal to noise of satellite observation (db.Hz)
unsigned character
1
Spare
double
8
Full carrier phase measurements in cycles.
double
8
Raw range to satellite (in seconds);
i.e., receive time - raw range = transmit time
long
4
Doppler (10
-4
Hz).
long
4
Bits 0 - 23: Smooth correction
(bit 0 - 22 = magnitude of correction in cms, bit 23 =
sign)
Bits 24 - 31: Smooth count, unsigned
(0 = unsmoothed; 1=least smoothed; 200 = most
smoothed)
(29)
P code on L1 block (same format as C/A code data
block)
(29)
P code on L2 block (same format as C/A code data
block)
unsigned character
1
Checksum, a bytewise exclusive OR (XOR)
total bytes
97