Woodward easYgen-3000XT Series, Руководство пользователя

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monitoring and communication between nodes, including a simple transport layer for
message segmentation/de-segmentation.
Protocol description
If a data protocol is used, a CAN message looks like this:
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
MUX Data byte Data byte Data byte Data byte Data byte Data byte Internal
The MUX byte is counted up, the meaning of the data byte changes according to the
value of the MUX byte.
In the protocol tables is listed which parameter at which MUX on which position is
transmitted. The meaning of the parameter can be taken by means of the number of the
parameter description (For details refer to
╚═▷ “9.2 Data Protocols” ).
☼
Example
MUX Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
1 118 147 Internal
In MUX 1 (byte 0 has got value 1) the value of parameter 118 is included in the byte 1
up to byte 4 (mains voltage 1-2). In byte 6 up to byte 6 the value of parameter 147 is
included (mains frequency). Byte 7 includes internal definitions and can be ignored.
Data format "Unsigned Integer"
UNSIGNED type data has positive integers as values. The range is between 0 and 2n-1.
The data is shown by the bit sequence of length n.
• Bit sequence: •
b = b
0
to b
–1
• Value shown: •
UNSIGNEDn(b) = b
–1
* 2
–1
+ ... + b
1
* 2
1
+ b
0
* 2
0
Please note that the bit sequence starts on the left with the least significant byte.
Example: Value 266 = 10A hex of type UNSIGNED16 is transmitted on the bus in two
octets, first 0A hex and then 01 hex.
The following UNSIGNED data types are transmitted as follows:
Octet Number 1. 2. 3. 4. 5. 6. 7. 8.
UNSIGNED8 b
7
to b
0
UNSIGNED16 b
7
to b
0
b
15
to b
8
UNSIGNED24 b
7
to b
0
b
15
to b
8
b
23
to b
16
UNSIGNED32 b
7
to b
0
b
15
to b
8
b
23
to b
16
b
31
to b
24
UNSIGNED40 b
7
to b
0
b
15
to b
8
b
23
to b
16
b
31
to b
24
b
39
to b
32
827 easYgen-3000XT Series B37574
7 Interfaces And Protocols
7.4 CANopen Protocol
Released