Noland Engineering RS11 v3.0 Manual page 8

APPENDIX A
CANbus Messages
CANbus networks such as J-1939 and NMEA 2000 send data in frames called 'messages'. Each message frame, or packet,
transmits a maximum of 8 data bytes, so longer messages require multiple packets. The message packets contain the message
ID along with the source and sometimes a destination addresses. The standard data rate is 250 Kbps.
J-1939 and NMEA 2000 protocols are similar because they are both derived from a parent Standard known as ISO 11783.
The ISO standard defines important protocol parameters such as data rates, address claiming, message id formats, etc. For
this reason J-1939, NMEA 2000, and ISO 11783 can share the same bus. The main difference between them is the specific
messages utilized by each protocol. NMEA 2000 messages are geared toward marine navigation applications, while J-1939 is
intended for large trucks and buses. The 3 standards also have different schemes for multi-packet messages. These protocols
can operate together on the same bus, but they may not understand each others' messages.
Each CANbus message is identified by a Parameter Group Number (PGN), which is embedded in the message frame. The
PGN specifically identifies the contents of each message. The table below lists the PGN's supported by the RS11. PGN's
below 65535 may be used by all 3 protocols, whereas those above belong strictly to NMEA 2000.
PGN Tx
59392
59904
60928 x
126464 x
126996 x
127488 x
127489 x
127493 Tx
127505 Tx
Engine Parameters Rapid Update
This short (single packet) message is sent 4 times/second for each engine. It contains RPM, Turbo Boost Pressure, and
Ttilt/trim indication. Separate messages are sent for Port and Starboard engines with each side using a unique "Instance ID".
Instance ID = 0 is used for Port or Single engine, while Instance ID=1 is for Starboard engine.
Engine Parameters Dynamic
This multi-packet message contains most of the important engine sensor information, which does not require fast updating. It
is sent once/second for each engine. The following data fields are contained in this message:
Table A1 RS11 Messages
Rx DESCRIPTION
Acknowledgement
x Request
x Address Claim
PGN List
Product Information
Engine Parameters Rapid Update
Engine Parameters Dynamic
Transmission Params
Fluid Level
MESSAGE DATA
Address and Name of device
List of Transmitted/Received PGN's by device.
Model id, Serial#, etc.
RPM, Turbo Boost, Tilt/trim
Oil Press., Eng. Temp., Batt. Volts, Oil Temp., etc.
Gear Oil Pressure , Temperature
Fuel level, Capacity