Init Commands

Init Commands are writes to SubDevice data objects that occur when a SubDevice transitions from one EtherCAT state to the next, for example from Pre-Op to Safe-Op.

Init commands are used to configure a SubDevice. Many SubDevices make use of Init Commands. Typically, they are defined by the ESI file, and perhaps by any Modules selections. Sometimes, you may need to add an Init command or modify an existing one to make sure the SubDevice is properly configured for the desired operation. Consult the SubDevice documentation and RMCTools help on specific third-party devices for instructions on when to add or modify Init commands.

Init Commands are listed in the EtherCAT Editor, on the Init Commands tab.

An Init Command has the following components:

Transition: Defines the state transition at which the write takes place
Protocol: This is always CoE.
Index: The address of the data object that is written to. This is in hexadecimal, with the number after the colon specifying a subindex.
Value: The value to be written.
Comment: A description of the data object specified by the Index.
Access: Specifies the read/write access.

The Index that the Init Command writes to can usually be found in the CoE Object Dictionary.

Creating and Editing Init Commands

Adding a New Init Command

In the Init Commands tab, click in the New button. The New CoE Init Command dialog opens.
In the CoE Object Dictionary box, browse to the desired object. If the object has subindexes, make sure to choose the correct one.
In the Value box, enter the desired value to write.
In the Transition section, choose the state transition for which the write should occur.
Click OK.

You can also create a new Init Command by using the Copy button:

In the Init Commands tab, in the Init Commands box, click the desired row.
Below the Init Commands box, click Copy. The New CoE Init Command dialog opens.
Makes edits as required, then click OK. This will create a new Init Command in the list.

Editing an Init Command

Editing just the value:

In the Init Commands tab, in the Init Commands box, click the desired row.
Below the Init Commands box, in the Edit Value section, in the Value box, enter the desired value, then press Enter.

Editing the details of the Init Command:

In the Init Commands tab, in the Init Commands box, click the desired row.
Below the Init Commands box, click Edit. The Edit CoE Init Command dialog opens.
Make changes as required, then click OK.

Reordering and Removing Init Commands

To reorder or remove Init commands, click an Init Command in the list, then use the Move Up, Move Down, or Delete button.

Common Init Commands

Some common Init commands that you may need to be aware of are:

Drives

This applies to drives conforming to the CiA402 specification. See using Drives with EtherCAT for more details.

• Op Mode (0x6060:00)

Defines whether the drive is in CSP mode (8) , CSV mode (9) or CST mode (10), as described in Drives Mode of Operation.

Valves

This applies to valves conforming to the CiA408 specification. See using Valves with EtherCAT for more details.

• Device Mode (0x6042)

This should be a value of 1 to specify that the setpoint command is via EtherCAT. A value of 2 indicates the valve will use its analog input for the setpoint command and will ignore the command received via EtherCAT.

• Device Control Mode (0x6043)

Typically, this should be set to 2, for spool position control closed-loop mode.

• Device local (0x604F)

This should be set to 0 to indicate that the Control Word source is via EtherCAT. A value of 1 indicates the valve will use local control (internal to the valve) and will ignore the Control Word data received via EtherCAT.