LF: CANopen Ladder Functions

UniStream supports the following Ladder functions:

SDO DownloadSDO Download

Use this function to download (write) a segment block of data (bytes) from the controller's Input Buffer to a node.

Download SDO using the required parameters: Index, Sub-Index, value to send, length according to the EDS file of your device.

Notes

  • Use the SDO in Progress from the CANopen General Struct in your application monitor in the activating conditions for this function

  • An application can run only one SDO Download function at a time.

 

 

Parameter

Type

Purpose

A

Node ID

UINT

Enter a constant or tag value to supply the ID of the remote device

B

Index

UINT16

The index of the remote device.

C

Sub-Index

UINT16

The Sub-Index of the remote device.

D

Segment Transfer Type

Selection

Select either:

  • Domain Segment Transfer

  • Block Segment Transfer

E

Number of Bytes to Download

UINT

Data length to write to remote device (bytes)

Max=40 bytes

F

Input Buffer

Register

Assign a register, buffer, or string to contain the data that is transmitted to the remote device.

SDO UploadSDO Upload

Use this function to upload (read) a segment block of data (bytes) from a node to the Output Buffer in the controller.

Upload SDO using the required parameters: Index, Sub-Index, value to send, length according to the EDS file of your device.

Notes

  • Use the SDO in Progress from the CANopen General Struct in your application monitor in the activating conditions for this function.

  • An application can run only one SDO Upload function at a time.

 

 

Parameter

Type

Purpose

A

Node ID

UINT

Enter a constant or tag value to supply the ID of the remote device

B

Index

UINT16

The index of the remote device.

C

Sub-Index

UINT16

The Sub-Index of the remote device.

D

Segment Transfer Type

Selection

Select either:

  • Domain Segment Transfer

  • Block Segment Transfer

E

Number of Bytes to Download

UINT

Data length to read from the remote device (bytes)

Maximum=40 bytes

F

Output Buffer

Register

Assign a register, buffer, or string to contain the data that is transmitted to the remote device.

 

Send NMT ControlSend NMT Control

This function enables you to send NMT Control messages.

Send NMT control

 

Parameter

Type

Purpose

A

Node ID

UINT

Enter a constant or tag value to supply the ID of the remote device.

ID 0 in order to broadcast from to all nodes.

B

Command

UINT16

Select Command:

1 Start Remote Node

2 Stop Remote Node

128 Enter Preoperational State

129 Reset Node

130 Reset Communication

 

 

Send NMT Node GuardSend NMT Node Guard

This is sometimes referred to as a 'heartbeat check'.

The Send NMT Node Guard function provides CANopen Node Guarding, checking node status.
The status returned from the node is stored in the node's NMT struct.

 

 

 

Parameter

Type

Purpose

A

Node ID

UINT

Enter a constant or tag value to supply the ID of the remote device

Send PDO/Send PDO RTRSend PDO/Send PDO RTR

The Send PDO function writes data to the node from the PLC master.

The Send PDO RTR function request data from the node, and reads data from the node to the PLC master.

 

Parameter

Type

Purpose

A

Node ID

UINT

Enter a constant or tag value to supply the ID of the remote device

B

PDO ID

UINT16

Select the number of the PDO assigned in the CANopen Configuration. CANopen Configuration.

Send SYNCSend SYNC

Use this function to synchronize tasks across the network.

Send TimeStampSend TimeStamp

Use this function to send a time stamp.