Configuring Parameters of Drives for Cyclic Data Exchange

Overview

To be able to set up the structure and contents of the MDTs and the ATs for cyclic communication, Sercos needs to know which of the drive-specific parameters provided by a drive are required for your application. The firmware adds a number of parameters by default. The remaining parameters need to be added by you. Refer to the chapter Sercos Parameters for general information on parameters.

Default Parameters

The following parameters are added by default when you add a drive as a slave device to the Sercos master:

S-0-0134 Drive control

This parameter sets the operating mode of a drive and triggers functions such as enabling and disabling the power stage as well as triggering Halt and Stop. Used in MDT.
S-0-0135 Drive status

This parameter provides the information on the status of a drive regarding the settings controlled with the parameter S-0-0134 Drive control. Used in AT.
S-0-0047 Position command value

This parameter sets the reference or target position for a drive. Unit, scaling, conversion factor, and positions after decimal point are configured with additional parameters. Used in MDT.
S-0-0051 Position feedback value

This parameter contains the actual position provided from a drive. Used in AT.
S-0-0390 Diagnostic number

This parameter contains detailed diagnostics information provided by a slave or sub-device. Used in AT.

Only the parameter S-0-0390 can be removed from the default mapping.

Adding Additional Parameters to the User-Specific Mapping List

Step	Action
1	Display the Device tree by clicking View > Navigators > Device tree.
2	In the tree of the Modicon M262 Motion Controller below the node SercosMaster (Sercos Master), double-click the Sercos slave to be configured.
3	Display the tab User Cyclic Data. The tab User Cyclic Data provides the panes Inputs (left) and Outputs (right). Inputs and outputs are seen from the perspective of the Sercos master. Parameters for cyclic input data are feedback values from the drive such as actual position, actual velocity, and diagnostics information. They are typically used in the ATs. Parameters for cyclic output data include, for example, target values for velocity or torque. They are typically used in the MDTs.
4	Click the button Add... in the Inputs or the Outputs pane, depending on the type of parameter you want to add. The dialog box Inputs configuration or Outputs configuration is displayed.
5	In the dialog box Inputs configuration or Outputs configuration, select single or multiple parameters from the list. The window Inputs configuration / Outputs configuration shows a list of the supported parameters per device. You can also add a parameter by entering its name and the additional values such as the function group (FG), structure instance (SI), or structure element (SE) in the appropriate fields. If you enter an invalid parameter, phase-up is not possible. The checkbox Supports CC lets you specify whether the parameter is to support cross-communication between slaves. The maximum number of parameters is limited by the drive. If you exceed the limit, phase-up is not possible. For optimum performance, only add the parameters actually required for the application.