Event Capture Attributes

These are the event-related attributes associated with a Motion Control Axis. These include registration, marker, and homing events. The Event Capture attributes are designed to support the possibility of up to seven active events per controller update period. The basis for all Time Stamp attributes is absolute System Time and follows the CIP Sync standard with 0 corresponding to January 1, 1970. Within the Logix controller, the System Time for event time stamps is converted to the local CST by applying the local System Time Offset to the event time stamp. In general, these event-related attributes are only applicable when there is an associated position feedback device; if the axis is configured for Encoderless or Sensorless operation, the event functionality is not applicable.

The Motion Control Axis supports two independent registration input channels per device axis instance that can be triggered on either the rising or falling edges of the signal. If the device hardware implementation allows, event time and position data can be captured for all four event conditions simultaneously. The Event Capture attributes also support Auto-rearm for registration events. This allows for controller implementation of important features like Windowed Registration and Registration Pattern Recognition.

The Motion Control Axis also supports Home Switch, Marker and Switch-Marker events for homing functionality on a per axis basis. The Marker events are typically generated by the configured position feedback device for the associated device axis.

Event Checking Control

*These attributes are updated via the cyclic Command Data Set of the CIP Motion C-to-D Connection. When included as cyclic command data, these attributes cannot not be updated via a Set service.

The Event Checking Control attribute is passed to the device by the controller as part of the Drive to Controller connection for the purpose of arming various device inputs, for example, marker, home switch, and registration inputs, to generate events to the controller. When these enabled events occur, the device captures both the time and exact axis position when the event occurred. This attribute also manages the format and content of the C2D Event Data Block.

Event Checking Status

The Event Checking Status attribute is passed by the device to the controller as part of the Drive to Controller connection to indicate if the device is currently checking for events based on various device inputs, for example, marker, home, and registration inputs. Event checking is initiated when the corresponding Event Checking Control bit is set in the controller to device connection. This attribute also manages the format and content of the D2C Event Data Block.

Registration Inputs

The Registration Inputs attribute determines the number of Registration Inputs supported by this device axis instance. Maximum value is determined by drive device profile.

Registration 1 Positive Edge Position

The Registration 1 Positive Edge Position attribute is the feedback position latched on the rising edge of the Registration Input 1.

Registration 1 Negative Edge Position

The Registration 1 Negative Edge Position attribute is the feedback position latched on the falling edge of the Registration Input 1.

Registration 2 Positive Edge Position

The Registration 2 Positive Edge Position attribute feedback position latched on the rising edge of the Registration Input 2.

Registration 2 Negative Edge Position

The Registration 2 Negative Edge Position attribute feedback position latched on the falling edge of the Registration Input 2.

Registration 1 Positive Edge Time

The Registration 1 Positive Edge Time attribute is the system time stamp on the rising edge of the Registration Input 1.

Registration 1 Negative Edge Time

The Registration 1 Negative Edge Time attribute is the system time stamp on the falling edge of the Registration Input 1.

Registration 2 Positive Edge Time

The Registration 2 Positive Edge Time attribute is the system time stamp on the rising edge of the Registration Input 2.

Registration 2 Negative Edge Time

The Registration 2 Negative Edge Time attribute is the system time stamp on the falling edge of the Registration Input 2.

Home Event Position

The Home Event Position attribute is the Feedback Position latched on the specified home event.

Home Event Time

The Home Event Time attribute is the system time stamp latched on the specified home event.

Watch 1 Event Time

The Watch 1 Event Time attribute is the system time stamp latched on the specified watch event.

Watch 2 Event Time

The Watch 2 Event Time attribute is the system time stamp latched on the specified watch event.

Home Torque Threshold

The Home Torque Threshold attribute sets the minimum torque level needed to detect the hard stop during a Home to Torque sequence. The drive’s output torque must exceed the specified Home Torque Threshold for the specified Home Torque Time. The units for Home Torque Threshold are expressed as a percentage of the operative Torque Limit, which during the homing sequence is set to the Home Torque Limit by the controller.

Valid for non-“immediate” cases of “active” Home Mode.

Valid for “home to torque” homing sequences.

Home Torque Time

The Home Torque Time attribute sets the minimum amount of time needed for the drive’s output torque to exceed the specified Home Torque Threshold to detect the hard stop during a Home to Torque sequence.

Valid for “home to torque” homing sequences.