Heinzmann Triton OMD, Manual

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3 HEINZMANN CAN protocol
Triton OMD CAN protocol / Rev.-No. 03 5
3 HEINZMANN CAN protocol
HEINZMANN CAN protocol is based on the CAN specification 2.0B with 29 bit identifier.
The identifier contains information about sender and receiver and the command code.
Maximum 8 data bytes are therefore available completely for operative data.
3.1 Identifier structure
Bit range Bit range Meaning Value
28…27 p priority always 2
26…23 d type of receiving device 0…15
22…18 m destination node number 0, 1….31
17 r reserved always 0
16…13 s type of sending device (source) 0…15
12…8 n source node number 1…31
7…0 c command 0…255
Tab. 3.1 Identifier structure
Each connection in a HEINZMANN CAN network is therefore a point-to-point connection. A
telegram is sent by a unique source to a unique destination. An exception is transmission of a
command to all units of the same type using node number 0.
3.2 Node types
Sources and destinations are subdivided in node type (device type) and a node number.
OMD sensor and OMD evaluator are internally treated as AC-devices and have device type
item of identifier equal to 5, which is used in telegram identifier.