Campbell Scientific SDM-CAN Datalogger to CANbus Interface User Manual
Page 71

Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding
24bit data frame with two 12bit unsigned integer values MSByte first
Rxed Bit order within bytes
87654321
87654321
87654321
Rxed Byte order
Byte 1
Byte 2
Byte 3
Values
B
A
Bit order within values
12 5 4 1
12 9 8 1
Value byte order
MSByte
LSNib
MSNib
LSByte
Start bit (parameter 09:) RH ref 24 17 16 13
12 9 8 1
Start bit (parameter 09:) LH ref 1 8 9 12
13 16 17 24
Start bit (parameter 09:) Right Hand reference.
1: SDM-CAN (P118)
1: 0
SDM
Address
2: 1
Time-quanta
3: 5
Tseg1
4: 2
Tseg2
5: 1000
ID
Bits
0..10
6: 0000
ID
Bits
11..23
7: 00
ID Bits 24..28
8: 1
Rx,
unsigned
int,
MSB
1st
9: 1
Start
Bit
No.
10: 12
No.
of
Bits
11: 2
No.
of
Values
12: 1
Loc [ value_A ]
13: 1.0
Mult
14: 0.0
Offset
Start bit (parameter 09:) Left Hand reference.
2: SDM-CAN (P118)
1: 00
SDM
Address
2: 1
Time-quanta
3: 5
Tseg1
4: 4
Tseg2
5: 1001
ID
Bits
0..10
6: 0000
ID
Bits
11..23
7: 00
ID
Bits
24..28
8: 1
Rx,
unsigned
int,
MSB
1st
9: 24
-- Start
Bit
No.
10: 12
No.
of
Bits
11: 2
No.
of
Values
12: 1
Loc [ value_A ]
13: 1.0
Mult
14: 0.0
Offset
D-9