3 process data telegram, 4 assignment of the user data to variables, Process data telegram – Lenze DDS System bus CAN for PLC User Manual

Page 100: Assignment of the user data to variables, System bus (can) for lenze plc devices, Can system blocks

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7.3

CAN1_IO (node number: 31) − ECSxA

System bus (CAN) for Lenze PLC devices

CAN system blocks

7−12

L

PLC−Systembus EN 2.0

7.3.3

Process data telegram

The process data telegram consists of an identifier and 8 bytes of user data.

11bit

8 bytes user data

Identifier

Byte 1

Byte 2

Byte 3

Byte 4

Byte 5

Byte 6

Byte 7

Byte 8

Information on the identifier can be found in chapter 2.4.1.

(

^ 2−3)

7.3.4

Assignment of the user data to variables

Several variables of different data types are assigned to the user data to be transmitted and received.
Thus, the data in the PLC program can be optionally interpreted as:

·

Binary information (1 bit)

·

Status word/quasi−analog value (16 bit)

·

Angle information (32 bit)

Variables for user data to be transmitted

User data

Assigned variables

Byte

Bit

Variable (1 bit)

Variable (16 bit)

Variable (32 bit)

1

0

...

7

CAN1_bFDO0_b

...

CAN1_bFDO7_b

CAN1_nOutW0_a

2

0

...

7

CAN1_bFDO8_b

...

CAN1_bFDO15_b

3

0

...

7

CAN1_bFDO16_b

...

CAN1_bFDO23_b

CAN1_nOutW1_a

4

0

...

7

CAN1_bFDO24_b

...

CAN1_bFDO31_b

5

0

...

7

CAN1_bFDO32_b

...

CAN1_bFDO39_b

CAN1_nOutW2_a

CAN1_dnOutD1_p

6

0

...

7

CAN1_bFDO40_b

...

CAN1_bFDO47_b

7

0

...

7

CAN1_bFDO48_b

...

CAN1_bFDO55_b

CAN1_nOutW3_a

8

0

...

7

CAN1_bFDO56_b

...

CAN1_bFDO63_b

Note!

Avoid simultaneous overwriting via different variable types to ensure data consistency.

For instance, if you want to write the bytes 5 and 6, only use the variable CAN1_dnOutD1_p,
CAN1_nOutW2_a, or only the variables CAN1_bFDO32_b ... CAN1_bFDO47_b for this purpose!

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