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Serial Port Output
83
Serial Port Output
The header field always contains "$PASHR". The message identifier field contains
a three character string and is followed by a field containing the binary data string.
The header, identifier, and data fields are comma delimited. Depending on the
message selected, the checksum is contained in the last one or two bytes of the
binary data string. All real-time messages are terminated with a Carriage Return/
Line Feed [CRLF] delimiter. The MBEN message comes out as shown below
when binary format is selected:
"$PASHR,MPC,<Binary Data String>[CRLF]"
The structure for messages output in ASCII format is similar, but the data string is
divided into comma delimited fields. Most of the fields contain numeric data
comprised of either integers, real numbers, or values in which integers and real
numbers are combined. The MBEN message has a three-digit checksum in the
last data field before the carriage return/line feed. The PBEN message does not
have a checksum when output in ASCII format:
"HEADER,MESSAGE ID,DATA+CHECKSUM[CRLF]"
The MBEN message comes out as shown below when ASCII format is selected:
"$PASHR,MPC,<ASCII Data String>*Checksum[CRLF]"
Table 4.2 contains symbols and the types of data represented by them used to
illustrate real-time message structures in the ASCII format:
MBEN Message
MBEN messages contain satellite measurement data, including satellite PRN,
elevation, azimuth, SNR, channel index, and more. MBEN can be output in either
ASCII or binary format. A separate message is generated for each tracked
satellite above the elevation mask. Table 4.3 and Table 4.4 outline the contents of
the MBEN message for the binary and ASCII formats.
Table 4.2.
ASCII Message Parameter Symbols
Symbol
Parameter Type
Example
d
Numeric integer
3
f
Numeric real
2.45
m
Combined numeric (integer and real) for lat/lon
037:21.0682
s
Character string
PALO
h
Hexadecimal number
A5