GNSS Module Series
GNSS SDK Commands Manual
GNSS_SDK_Commands_Manual Confidential / Released 7 / 28
2
Quectel NMEA Packet Protocol
This chapter introduces the Quectel NMEA packet protocol which is a set of extension messages of the
standard NMEA packet protocol. These messages are used to control and configure Quectel L70, L80,
L76, L76-L, L86 and L26 modules.
The structure of Quectel NMEA packet is shown as below:
2.1. Quectel NMEA Packet Format
Preamble
TalkerID
PktType
DataField
*
CHK1 CHK2 CR
LF
Packet Contents:
Preamble:
One byte character.
‘
$’
TalkerID:
Two bytes character string.
“
PQ
“
PktType:
1-10 bytes character string.
An identifier used to tell the decoder how to decode the packet.
DataField: The DataFileld has variable lengths depending on the packet type.
A command symbol ‘,’ must be inserted ahead of each data filed to help the decoder
process the DataField.
* :
1 byte character.
The star symbol is used to mark the end of DataField.
CHK1, CHK2: Two bytes character string.
CHK1 and CHK2 are the check sum of the data between Preamble and ‘*’.
CR, LF:
Two bytes binary data.
The two bytes are used to identify the end of a packet.
The maximum length of each packet is restricted to 255 bytes.
NOTE
Quectel
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