AXIS_SERVO Structure

A servo axis object represents an axis with full motion planner functionality and integrated configuration support.
A servo axis object is associated with modules that close a servo loop and send an analog command to an external drive, such as the 1756-M02AE and 1756-HYD02 modules. The AXIS_SERVO structure contains the following status attributes.
Mnemonic
Data Type
Description
MotionStatus
DINT
The motion status bits for your axis.
Bit #
Bit Name (tag)
Description
BOOL
00
AccelStatus
Acceleration Status
BOOL
01
DecelStatus
Deceleration Status
BOOL
02
MoveStatus
Move Status
BOOL
03
JogStatus
Jog Status
BOOL
04
GearingStatus
Gearing Status
BOOL
05
HomingStatus
Homing Status
BOOL
06
StoppingStatus
Stopping Status
BOOL
07
AxisHomedStatus
Homed Status
BOOL
08
PositionCamStatus
Position Cam Status
BOOL
09
TimeCamStatus
Time Cam Status
BOOL
10
PositionCamPendingStatus
Position Cam Pending Status
BOOL
11
TimeCamPendingStatus
Time Cam Pending Status
BOOL
12
GearingLockStatus
Gearing Lock Status
BOOL
13
PositionCamLockStatus
Position Cam Lock Status
BOOL
14
TimeCamLockStatus
Time Cam Lock Status
BOOL
15
MasterOffsetMoveStatus
Master Offset Move Status
AxisStatus
DINT
The status bits for your axis:
BOOL
Bit #
Bit Name (tag)
Description
BOOL
00
ServoActionStatus
Servo Action Status
BOOL
01
DriveEnableStatus
Drive Enable Status
BOOL
02
ShutdownStatus
Axis Shutdown Status
BOOL
03
ConfigUpdateInProcess
Configuration Update in Process
AxisFault
DINT
The axis faults for your axis:
Bit #
Bit Name (tag)
Description
BOOL
00
PhysicalAxisFault
Physical Axis Fault
BOOL
01
ModuleFault
Module Fault
BOOL
02
ConfigFault
Configuration Fault
BOOL
03
GroupFault
Group Fault
AxisEvent
DINT
The event status for your axis:
Bit #
Bit Name (tag)
Description
BOOL
00
WatchEvArmStatus
Watch Event Armed Status
BOOL
01
WatchEvStatus
Watch Event Status
BOOL
02
RegEvArmStatus
Registration Event 1 Armed Status
BOOL
03
RegEvStatus
Registration Event 1 Status
BOOL
04
RegEv2ArmStatus
Registration Event 2 Armed Status
BOOL
05
RegEv2Status
Registration Event 2 Status
BOOL
06
HomeEvArmStatus
Home Event Armed Status
BOOL
07
HomeEvStatus
Home Event Status
ActualPosition
REAL
Actual Position in Position Units
StrobeActualPosition
REAL
Strobe Actual Position in Position Units
StartActualPosition
REAL
Start Actual Position in Position Units
AverageVelocity
REAL
Average Velocity in Position Units / Sec
ActualVelocity
REAL
Actual Velocity in Position Units / Sec
ActualAcceleration
REAL
Actual Acceleration in Position Units / Sec
2
WatchPosition
REAL
Watch Position in Position Units
RegistrationPosition
REAL
Registration 1 Position in Position Units
Registration2Position
REAL
Registration 2 Position in Position Units
Registration1Time
DINT
Registration 1 Time as CST time in microseconds
Registration2Time
DINT
Registration 2 Time as CST time in microseconds
InterpolationTime
DINT
Interpolation Time as CST time in microseconds
InterpolatedActualPosition
REAL
Interpolated Actual Position in Position Units
MasterOffset
REAL
Master Offset in Master Position Units
StrobeMasterOffset
REAL
Strobe Master Offset in Master Position Units
StartMasterOffset
REAL
Start Master Offset in Master Position Units
CommandPosition
REAL
Command Position in Position Units
StrobeCommandPosition
REAL
Strobe Command Position in Position Units
StartCommandPosition
REAL
Start Command Position in Position Units
CommandVelocity
REAL
Command Velocity in Position Units / Sec
CommandAcceleration
REAL
Command Acceleration in Position Units / Sec
2
InterpolatedCommandPosition
REAL
Interpolated Command Position in Position Units
ServoStatus
DINT
The status bits for your servo loop:
Bit #
Bit Name (tag)
Description
BOOL
00
- no tag -
Servo Action Status
BOOL
01
- no tag -
Drive Enable Status
BOOL
02
- no tag -
Axis Shutdown Status
BOOL
03
ProcessStatus
Process Status
BOOL
04
OutLmtStatus
Output Limit Status
BOOL
05
PosLockStatus
Position Lock Status
BOOL
06
HomeSwitchStatus
Home Input Status
BOOL
07
Reg1InputStatus
Registration 1 Input Status
BOOL
08
Reg2InputStatus
Registration 2 Input Status
BOOL
09
PosOvertravelInputStatus
Positive Overtravel Input Status
BOOL
10
NegOvertravelInputStatus
Negative Overtravel Input Status
BOOL
11
DriveFaultInputStatus
Drive Fault Input Status
ServoFault
DINT
The servo fault bits for your servo loop:
Bit #
Bit Name (tag)
Description
BOOL
00
POtrvlFault
Positive Software Overtravel Fault
BOOL
01
NOtrvlFault
Negative Software Overtravel Fault
BOOL
02
PosHardOvertravelFault
Positive Hardware Overtravel Fault
BOOL
03
NegHardOvertravelFault
Negative Hardware Overtravel Fault
BOOL
04
FeedbackFault
Feedback Fault
BOOL
05
FeedbackNoiseFault
Feedback Noise Fault
BOOL
06
AuxFeedbackFault
Auxiliary Feedback Fault
BOOL
07
AuxFeedbackNoiseFault
Auxiliary Feedback Noise Fault
BOOL
08
PosErrorFault
Position Error Fault
BOOL
09
DriveFault
Drive Fault
ServoModuleFault
DINT
A collection of all faults that have module scope as opposed to axis scope. These module faults are reflected by all axes supported by the given servo module.
Bit #
Bit Name (tag)
Description
BOOL
00
ControlSyncFault
Control Sync Fault
BOOL
01
ModuleSyncFault
Module Sync Fault
BOOL
02
TimerEventFault
Timer Event Fault
BOOL
03
ModuleHardwareFault
Module Hardware Fault
AttributeErrorCode
INT
CIP Error code returned by erred set attribute list service to the module. (See CIP Error Code list)
AttributeErrorID
INT
Attribute ID associated with non-zero Attribute Error Code. (See CIP Error Code list)
PositionCommand
REAL
Position Command in Position Units
PositionFeedback
REAL
Position Feedback in Position Units
AuxPositionFeedback
REAL
Auxiliary Position Feedback in Position Units
PositionError
REAL
Position Error in Position Units
PositionIntegratorError
REAL
Position Integrator Error in Position Units - mSec
VelocityCommand
REAL
Velocity Command in Position Units / Sec
VelocityFeedback
REAL
Velocity Feedback in Position Units / Sec
VelocityError
REAL
Velocity Error in Position Units / Sec
VelocityIntegratorError
REAL
Velocity Integrator Error in Position Units – mSec / Sec
AccelerationCommand
REAL
Acceleration Command in Position Units / Sec
2
AccelerationFeedback
REAL
Acceleration Feedback in Position Units / Sec
2
ServoOutputLevel
REAL
Servo Output Level in Volts
MarkerDistance
REAL
Marker Distance in Position Units
VelocityOffset
REAL
Velocity Offset in Position Units / Sec (not enabled in this release)
TorqueOffset
REAL
Torque Offset from –100% to +100% (not enabled in this release)
AccelStatus
BOOL
Set if the axis is currently being commanded to accelerate.
DecelStatus
BOOL
Set if the axis is currently being commanded to decelerate.
MoveStatus
BOOL
Set if a Move motion profile is currently in progress. Cleared when the Move is complete or is superseded by some other motion operation.
JogStatus
BOOL
Set if a Jog motion profile is currently in progress. Cleared when the Jog is complete or is superseded by some other motion operation.
GearingStatus
BOOL
Set if the axis is currently Gearing to another axis. Cleared when the gearing operation is stopped or is superseded by some other motion operation.
HomingStatus
BOOL
Set if a Home motion profile is currently in progress. Cleared when the homing operation is stopped or is superseded by some other motion operation.
StoppingStatus
BOOL
Set if there is a stopping process currently in progress. Cleared when the stopping process is complete.
Tip
: The stopping process is used to stop an axis (initiated by an MAS, MGS, Stop Motion fault action, or mode change). This bit is no longer associated with the gearing Clutch bit (MAG with Clutch selected) which, for I4B, has been explicitly named the Gearing Lock Status bit.
AxisHomedStatus
BOOL
Cleared at power-up or reconnection. Set by the MAH instruction upon successful completion of the configured homing sequence, and later cleared when the axis enters the shutdown state.
PositionCamStatus
BOOL
Set if a Position Cam motion profile is currently in progress. Cleared when the Position Cam is complete or is superseded by some other motion operation.
TimeCamStatus
BOOL
Set if a Time Cam motion profile is currently in progress. Cleared when the Time Cam is complete or is superseded by some other motion operation.
PositionCamPendingStatus
BOOL
Set if a Position Cam motion profile is currently pending the completion of a currently executing cam profile. This would be initiated by executing an MAPC instruction with Pending execution selected. This bit is cleared when the current position cam profile completes, initiating the start of the pending cam profile. This bit is also cleared if the position cam profile completes, or is superseded by some other motion operation.
TimeCamPendingStatus
BOOL
Set if a Time Cam motion profile is currently pending the completion of a currently executing cam profile. This would be initiated by executing an MATC instruction with Pending execution selected. This bit is cleared when the current time cam profile completes, initiating the start of the pending cam profile. This bit is also cleared if the time cam profile completes, or is superseded by some other motion operation.
GearingLockStatus
BOOL
Set whenever the slave axis is locked to the master axis in a gearing relationship according to the specified gear ratio. The clutch function of the gearing planner is used to ramp an axis up, or down, to speed in a gearing process (MAG with Clutch selected). This bit is cleared during the intervals where the axis is clutching.
PositionCamLockStatus
BOOL
Set whenever the master axis satisfies the starting condition of a currently active Position Cam motion profile. The starting condition is established by the Start Control and Start Position parameters of the MAPC instruction. This bit is bit is cleared when the current position cam profile completes, or is superseded by some other motion operation. In uni-directional master direction mode, the Position Cam Lock Status bit is cleared when moving in the "wrong" direction and sets when moving in the "correct" direction.
TimeCamLockStatus
BOOL
Time Cam Lock Status (not enabled in this release)
MasterOffsetMoveStatus
BOOL
Set if a Master Offset Move motion profile is currently in progress. This bit is cleared when the Master Offset Move is complete or is superseded by some other motion operation.
ServoActionStatus
BOOL
Set when the associated axis is under servo control. Cleared when servo action is disabled.
DriveEnableStatus
BOOL
Set when the Drive Enable output of the associated physical axis is currently enabled. Cleared when physical servo axis Drive Enable output is currently disabled.
ShutdownStatus
BOOL
Set when the associated axis is currently in the Shutdown state. Cleared when the axis is transitioned from the Shutdown state to another state.
ConfigUpdateInProcess
BOOL
The Configuration Update Status Bits attribute provides a method for monitoring the progress of one or more specific module configuration attribute updates initiated by either a Set Attribute List service (which is internal to the firmware) or an SSV in the user program. When such an update is initiated, the
ControlLogix
processor sets this bit. This bit will remain set until the Set Attribute List reply comes back from the servo module indicating that the data update process was successful. Thus the Configuration Update Status Bits attribute provides a method of waiting until the servo configuration data update to the connected motion module is complete before starting a dependent operation.
PhysicalAxisFault
BOOL
Set when one or more fault conditions have been reported by the physical axis. The specific fault conditions can then be determined through access to the fault attributes of the associated physical axis.
ModuleFault
BOOL
Set when a serious fault has occurred with the motion module associated with the selected axis. Usually a module fault affects all axes associated with the motion module. A module fault generally results in the shutdown of all associated axes. Reconfiguration of the motion module is required to recover from a module fault condition.
ConfigFault
BOOL
Set when an update operation targeting an axis configuration attribute of an associated motion module has failed. Specific information concerning the Configuration Fault may be found in the Attribute Error Code and Attribute Error ID attributes associated with the motion module.
WatchEvArmStatus
BOOL
Set when a watch event has been armed through execution of the MAW (Motion Arm Watch) instruction. Cleared when either a watch event occurs or a MDW (Motion Disarm Watch) instruction is executed.
WatchEvStatus
BOOL
Set when a watch event has occurred. Cleared when either another MAW (Motion Arm Watch) instruction or a MDW (Motion Disarm Watch) instruction is executed.
RegEvArmStatus
BOOL
Set when a registration checking has been armed for registration input 1 through execution of the MAR (Motion Arm Registration) instruction. Cleared when either a registration event occurs or a MDR (Motion Disarm Registration) instruction is executed for registration input 1.
RegEvStatus
BOOL
Set when a registration event has occurred on registration input 1. Cleared when either another MAR (Motion Arm Registration) instruction or a MDR (Motion Disarm Registration) instruction is executed for registration input 1.
RegEv2ArmStatus
BOOL
Set when a registration checking has been armed for registration input 2 through execution of the MAR (Motion Arm Registration) instruction. Cleared when either a registration event occurs or a MDR (Motion Disarm Registration) instruction is executed for registration input 2.
RegEv2Status
BOOL
Set when a registration event has occurred on registration input 2. Cleared when either another MAR (Motion Arm Registration) instruction or a MDR (Motion Disarm Registration) instruction is executed for registration input 2.
HomeEvArmStatus
BOOL
Set when a home event has been armed through execution of the MAH (Motion Axis Home) instruction. Cleared when a home event occurs.
HomeEvStatus
BOOL
Set when a home event has occurred. Cleared when another MAH (Motion Axis Home) instruction is executed.
ProcessStatus
BOOL
Set when there is an axis tuning operation or an axis hookup diagnostic test operation in progress on the associated physical axis.
OutLmtStatus
BOOL
Set when the magnitude of the output of the associated physical servo axis has reached or exceeded the configured Output Limit value.
PosLockStatus
BOOL
Set when the magnitude of the axis position error has become less than or equal to the configured Position Lock Tolerance value for the associated physical axis.
HomeSwitchStatus
BOOL
Set when the current state of the dedicated Home input is active. Cleared when the Home input is inactive.
Reg1InputStatus
BOOL
Set when the current state of the dedicated Registration 1 input is active. Clear when the Registration 1 input is inactive.
Reg2InputStatus
BOOL
Set when the current state of the dedicated Registration 1 input is active. Clear when the Registration 1 input is inactive.
PosOvertravelInputStatus
BOOL
Set when the current state of the dedicated Positive Overtravel input is active. Clear when the Positive Overtravel input is inactive. (not enabled in this release).
NegOvertravelInputStatus
BOOL
Set when the current state of the dedicated Negative Overtravel input is active. Clear when the Negative Overtravel input is inactive. (not enabled in this release).
DriveFaultInputStatus
BOOL
Set then the current state of the Drive Fault Input is active. Cleared when the Home Input is inactive.
POtrvlFault
BOOL
Set when the axis has traveled, or attempted to travel, beyond the current configured value for Maximum Positive Travel. Cleared when the axis is moved back within this travel limit.
NOtrvlFault
BOOL
Set when the axis has traveled, or attempted to travel, beyond the current configured value for Maximum Negative Travel. Cleared when the axis is moved back within this travel limit.
PosHardOvertravelFault
BOOL
Set when the axis has traveled beyond the current positive direction position limits as established by hardware limit switches mounted on the machine. To recover, the axis must be moved back with normal operation limits of the machine and the limit switch reset. This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear. (not enabled in this release).
NegHardOvertravelFault
BOOL
Set when the axis has traveled beyond the current negative direction position limits as established by hardware limit switches mounted on the machine. To recover, the axis must be moved back with normal operation limits of the machine and the limit switch reset. This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear. (not enabled in this release)
FeedbackFault
BOOL
Set for a specific feedback source when one of the following conditions occurs:
The differential electrical signals for one or more of the feedback channels (e.g., A+ and A-, B+ and B-, or Z+ and Z-) are at the same level (both high or both low). Under normal operation, the differential signals are always at
opposite
levels. The most common cause of this situation is a broken wire between the feedback transducer and the servo module or drive; or
Loss of feedback "power" or feedback "common" electrical connection between the servo module or drive and the feedback device.
This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear.
FeedbackNoiseFault
BOOL
Set for a specific feedback source when the servo module has detected simultaneous transitions of the feedback A and B channels (called "feedback noise"). Feedback noise is most often caused by loss of quadrature in the feedback device itself or radiated common-mode noise signals being picked up by the feedback device wiring, both of which may be able to be seen on an oscilloscope. This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear.
AuxFeedbackFault
BOOL
Set for an auxiliary feedback source when one of the following conditions occurs:
The differential electrical signals for one or more of the feedback channels (e.g., A+ and A-, B+ and B-, or Z+ and Z-) are at the same level (both high or both low). Under normal operation, the differential signals are always at
opposite
levels. The most common cause of this situation is a broken wire between the feedback transducer and the servo module or drive; or
Loss of feedback "power" or feedback "common" electrical connection between the servo module or drive and the feedback device.
This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear. (not enabled in this release).
AuxFeedbackNoiseFault
BOOL
Set for an auxiliary feedback source when the servo module has detected simultaneous transitions of the feedback A and B channels (called "feedback noise"). Feedback noise is most often caused by loss of quadrature in the feedback device itself or radiated common-mode noise signals being picked up by the feedback device wiring, both of which may be able to be seen on an oscilloscope. This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear. (not enabled in this release).
PosErrorFault
BOOL
Set when the servo has detected that the axis position error has exceeded the current configured value for Position Error Tolerance. This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear.
DriveFault
BOOL
Set when the external servo drive has detected a fault and has communicated the existence of this fault to the servo module via the Drive Fault input. This fault condition is latched and requires execution of an explicit MAFR (Motion Axis Fault Reset) or MASR (Motion Axis Shutdown Reset) instruction to clear.
ControlSyncFault
BOOL
Set when the Logix controller detects that several position update messages in a row from the motion module have been missed due to a failure of the synchronous communications connection. This condition results in the automatic shutdown of the associated servo module. The Logix controller is designed to "ride-through" a maximum of four missed position updates without issuing a fault or adversely affecting motion in progress. Missing more than four position updates in a row constitutes a problematic condition that warrants shutdown of the servo module. This fault bit is cleared when the connection is reestablished.
ModuleSyncFault
BOOL
Set when the motion module detects that several position update messages in a row from the
ControlLogix
processor module have been missed due to a failure of the synchronous communications connection. This condition results in the automatic shutdown of the servo module. The servo module is designed to "ride-through" a maximum of four missed position updates without issuing a fault or adversely affecting motion in progress. Missing more than four position updates in a row constitutes a problematic condition that warrants shutdown of the servo module. This fault bit is cleared when the connection is reestablished.
TimerEventFault
BOOL
Set when the associated servo module has detected a problem with the module’s timer event functionality used to synchronize the motion module’s servo loop to the master timebase of the Logix rack (i.e. Coordinated System Time). This fault bit can be cleared only by reconfiguration of the motion module.
ModuleHardwareFault
BOOL
Set when the associated servo module has detected a hardware problem that, in general, is going to require replacement of the module to correct.
OutputCamStatus
DINT
A set of bits * that are set when the Output Cam has been initiated.
OutputCamPendingStatus
DINT
A set of bits * that are set when an Output Cam is waiting for an armed Output Cam to move beyond its cam start/cam end position.
OutputCamLockStatus
DINT
A set of bits * that are set when an Output Cam is locked to the master axis.
OutputCamTransitionStatus
DINT
A set of bits * that are set when the transition from the current armed Output Cam to the pending Output Cam is in process.
* The bit number corresponds with the execution target number. One bit per execution target.
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