Chapter 7 Can Bus - Novatel SMART7 Installation And Operation Manual

Chapter 7 CAN Bus

The OEM7 receivers support the following CAN protocols:
J1939 Transport and Extended Transport Protocol: used for corrections and NovAtel mes-
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sages (both transmitting and receiving)
NMEA2000: used for standard as well as NovAtel-proprietary messages (transmitting only)
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By default, CAN is disabled on OEM7 receivers. Critical CAN configuration parameters such as
Parameter Group Numbers (PGNs), addresses and priorities are system-specific and must be
explicitly configured.
The addresses and PGNs are typically allocated when the overall CAN bus topology is determ-
ined. A Node has a unique CAN J1939 NAME and address.
The SMART7 has internal CAN transceivers, however they still require proper bus
terminations.
Refer to Table 27: SMART7 Connector Pin Out on page 136 for pin-out information.
OEM7 receivers support the following NMEA2000 Parameter Group Messages (PGN) over the
CAN bus:
PGN 126992 System Time
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PGN 129025 GNSS Position Rapid Update
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PGN 129026 COG & SOG Rapid Update
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PGN 129027 Position Delta High Precision Rapid Update
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PGN 129029 GNSS Position
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PGN 129551 GNSS Differential Signal
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The following commands and logs are used for CAN configuration:
CANCONFIG command: controls the CAN transceiver hardware and places the receiver on
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bus or off bus
J1939CONFIG command: assigns the CAN J1939 NAME and address parameters to a Node
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J1939STATUS log: reports the status a Node on the J1939 CAN network, such as the
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claimed address
LOG CCOMx PGNabcd: configures the NMEA2000 messages
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PGNCONFIG command: configures the NovAtel-proprietary NMEA2000 messages (change
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the PGN and its priority)
CCOMCONFIG command: configures the parameters used by the NovAtel command inter-
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face to interact with the CAN Bus
CCOM ports with a lower port number have a higher transmission priority.
SMART7 Installation and Operation User Manual 0C 99