SMART7 Installation and Operation User Manual v6
100
Chapter 8 CAN Bus
The OEM7 receivers support the following CAN protocols:
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J1939 Transport and Extended Transport Protocol: used for corrections and NovAtel messages (both trans-
mitting and receiving)
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NMEA2000: used for standard as well as NovAtel-proprietary messages (transmitting only)
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 determined. 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 28: SMART Antenna Interface Cable Connector Pin Out
on page 142 for pin-out information.
OEM7 receivers support the following NMEA2000 Parameter Group Messages (PGN) over the CAN bus:
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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
The following commands and logs are used for CAN configuration:
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CANCONFIG
command: controls the CAN transceiver hardware and places the receiver
on bus
or
off bus
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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 claimed address
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LOG CCOMx PGNabcd
: configures the NMEA2000 messages
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CCOMCONFIG
command: configures the parameters used by the NovAtel command interface to interact
with the CAN Bus.
CCOM ports with a lower port number have a higher transmission priority.
For information about these commands, see the
Agriculture Commands and Logs Reference Manual
.
Details for the PGN messages can be found in the NMEA2000 specification which can be purchased
directly from the National Marine Electronics Association (
).