Campbell Scientific SDM-CAN Datalogger to CANbus Interface User Manual

Page 64

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Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding

Examples of values within a data-frame

16bit data frame with a one value 16bit unsigned integer LSByte first

Rxed Bit order within bytes

87654321

87654321

Rxed Byte order

Byte 1

Byte 2

Values

A

Bit order within values

8 1

16 9

Value byte order

LSByte

MSByte

Start bit (parameter 09:) RH ref

16 9

8 1

Start bit (parameter 09:) LH ref

1 8

9 16

This number is
entered into the
P118 DLD
instruction

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: 2

Rx, unsigned int, LSB 1st

9: 9

Start

Bit

No.

10: 16

No.

of

Bits

11: 1

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: 2

Rx, unsigned int, LSB 1st

9: 8

-- Start

Bit

No.

10: 16

No.

of

Bits

11: 1

No.

of

Values

12: 1

Loc [ value_A ]

13: 1.0

Mult

14: 0.0

Offset

D-2

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