RMF Systems CMS 2, Руководство пользователя

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As a policy of continual improvement, RMF reserves the right to alter the specification without prior notice.
201.028 REV 1 Date of Issue: 18 June 2018
11.2.2 Messages
11.2.2.1 CAN2.0B and J1939
The CMS CAN-bus implementation is designed to be interoperable with J1939 networks. This is done by
restricting CAN-bus message IDs to those within the proprietary ranges allocated by J1939. Advanced J1939
features have been avoided, so that customers not using J1939 will also be able to communicate using ``generic’’
CAN-bus frames. For non-J1939 users the only requirement is that their network should support CAN2.0 (29 bit
identifiers).
Broadcast messages use the J1939 PDU2 format. These are transmitted periodically to communicate the CMS
status and the latest test results.
Peer-to-peer messages use the J1939 PDU1 format. These are used to control the CMS. These are generally
optional; customers may opt to leave the CMS automatically testing and broadcasting results.
Node Address (PDU1) 0x3F (J1939 “Oil Sensor”)
Command & Configuration Message PGN 0xEF3F
Broadcast Messages PGNs 0xFFB5 – 0xFFB9
Default Broadcast Interval 1s
Data Page 0
Priority 6
PDU Format/ PDU specific Derived from PGN
Byte Endianness All data is on little-endian byte order
Table 11F CAN-bus Parameters for J1939 Interoperation
11.2.2.2 Non-J1939 CAN2.0B Users
−
Taken together these imply a generic CAN "base address" of 0x18FFB53F.
−
Command and control messages can then be sent to CAN address 0x18EF3F00.
11.2.2.3 CAN2.0A and CanOpen
On CanOpen networks the results need to be transmitted as ``process data objects’’ (PDOs) from the ``pre defined
connection set’’. In order to do this, ensure that the set base address is equal to (0x180 + node number). For
example, 0x182 to make the CMS node address 2.
11.2.2.4 CAN-bus Message List
The message ID numbers shown are examples only and are dependent on the set base address.
For CAN2.0A/CanOpen we have an example base address of 0x182. So you see ``2’’ as the last digit of the entire
message IDs. CanOpen interprets this as the device node number.
For CAN2.0B/J1939 we have an example base address
of 0x18FFB53F. The equivalent node number is ``3F’’ so you
see this appear in all the message IDs.
For other node numbers change the set base address value as required. CanOpen has node numbers from 0x01 to
0x7f. J1939 has node numbers from 0x01 to 0xff.