Status Bits for MCLM, MCCM when MDCC Is Active

This table describes the predefined data type status bits for motion instruction MCLM and MCCM.
Bit Name
Meaning
FLAGS
EN
DN
ER
PC
IP
AC
ACCEL
Set as expected during motion. It is independent of Master acceleration.
The ACCEL bit on the instruction driving the Slave Coordinate System (for example, MCLM) is set as the Slave Coordinate System is accelerating to its commanded speed. This bit is insensitive to acceleration occurring on the Master Axis.
However, the AccelStatus bit, which is in the MotionStatus word of the Slave Coordinate System (not the instruction driving the Slave Coordinate System), is set or cleared based on changes in velocity of the Slave Coordinate System.
DECEL
Set as expected during motion. It is independent of Master deceleration.
The DECEL bit on the instruction driving the Slave Coordinate System is set as the Slave Coordinate System is decelerating to its commanded speed. This bit is insensitive to deceleration occurring on the Master Axis.
However, the DecelStatus bit, which is in the MotionStatus word of the Slave Coordinate System (not the instruction driving the slave axis), is set or cleared based on changes in velocity of the Slave Coordinate System.
TrackingMaster
Indicates that the Slave Coordinate System is tracking the Master Axis (only used in Master Driven Mode).
When an instruction is initiated in Master Driven Mode, the Slave Coordinate System accelerates to the speed that is programmed for MDSC mode. The Tracking Master is set when the acceleration is complete in MDSC Mode. This means that the Slave Coordinate System is synchronized to the Master Axis.
The Tracking Master bit is cleared when any of the following occurs on the Slave Coordinate System:
  • When the Slave Coordinate System starts to either accelerate or decelerate for any reason, for example, for an MCCD or an MCS being issued.
  • When the Slave Coordinate System is relinked to another Master Axis. In this situation, the TrackingMaster bit is first cleared and then it is set again in the new instruction status word when the Slave Coordinate System starts tracking the new Master Axis again.
  • The Slave Coordinate System is stopped. The Tracking Master is cleared as soon as the stop is initiated on the Slave Coordinate System.
This bit is never set when LockDir = NONE.
Note that the Tracking Master bit on the Slave Coordinate System is not affected by any operation (for example, MCS, MCCD) on the Master Axis.
The Tracking Master bit is always cleared in Time Driven Mode.
CalculatedDataAvailable
Indicates that the requested data has been returned in the Calculated Data array element and that the
Logix Designer
 application has updated the output data in the Calculated Data parameter. Only one status bit is used to indicate all Calculated Data is available.
For the CalculatedDataAvailabe status bit, the moves in the motion queue are processed in batches. The first batch in the motion queue includes all moves in the queue up to and including the first move with a term type TT0 or TT1, or a move with a speed of 0.
For moves in either Time Driven mode or Mater Driven mode, the CalculatedDataAvailable bit is set when:
  • MCLM or MCCM is enqueued and belongs to the first batch in the queue. There are two exceptions:
    • Moves with a speed of 0, although belonging to the first batch, do not have their CalculatedDataAvailable bit set. Their CalculatedDataAvailable bit is set after their Speed is changed to nonzero with a MCCD.
    • Moves with a term type TT2 through TT6 do not have their CalculatedDataAvailable bit set if they are the last move in the queue.
CalculatedDataAvailable bit is cleared by:
  • MAS (all) or MASD - This clears the CalculatedDataAvailable bit of the active MAMs and all enqueued MCLM or MCCMs that contain the specified axis.
  • MCS (coordinated) - This only clears the CalculatedDataAvailable bit for all enqueued MCLM or MCCMs in the coordinate system being stopped.
  • MCS (all) or MCSD - This clears the CalculatedDataAvailable bit of all active MAMs that contain any axes in the referenced coordinate system and all enqueued MCLM or MCCMs of the coordinate system being stopped.
  • MGS or MGSD is executed (goes IP) - This clears the CalculatedDataAvailable bit of all active MAMs and all enqueued MCLM or MCCMs of the group being stopped or shutdown.
  • MCD or MCCD is executed (goes IP) - The CalculatedDataAvailable bit is reset and is immediately set again.
  • A MCLM or MCCM is executed (goes IP) with a merge enabled (either Coordinated or Merge All) - The CalculatedDataAvailable bit of all enqueued MCLM or MCCMs are cleared.
MCLMs and MCCMs that are blending with the next coordinated motion instruction are still considered to be enqueued even if their PC flag was set when the blending was started.
The CalculatedDataAvailable bit is not set for any move that Event Distance is not specified (that is, for any move where the Event Distance parameter in the instruction is zero).
MSF and MDF do not alter the state of the CalculatedDataAvailable bit.
Coordinated Motion Status Bits
Bit Name
Meaning
CoordinateMotionStatus
Set when an axis lock is requested for an MCLM or MCCM instruction and the axis has crossed the Lock Position. Cleared when an MCLM or MCCM is initiated.
AccelStatus
Sets when vector is accelerating. Clears when a blend is in process or when vector move is at speed or decelerating.
DecelStatus
Sets when vector is decelerating. Clears when a blend is in process or when vector move is accelerating or when move completes.
ActualPosToleranceStatus
Sets for Actual Tolerance termination type only. The bit is set after the following two conditions have been met. 1) Interpolation is complete. 2) The actual distance to the programmed endpoint is less than the configured coordinate system’s Actual Tolerance value. It remains set after the instruction completes. It is reset when a new instruction is started.
CommandPosToleranceStatus
Sets for all termination types whenever the distance to the programmed endpoint is less than the configured coordinate system’s Command Tolerance value and remains set after the instruction completes. It is reset when a new instruction is started.
StoppingStatus
The Stopping Status bit is cleared when the MCCM instruction executes.
MoveStatus
Sets when MCCM begins axis motion. Clears on the .PC bit of the last motion instruction or a motion instruction executes which causes a stop.
MoveTransitionStatus
Sets when No Decel or Command Tolerance termination type is satisfied. When blending collinear moves the bit is not set because the machine is always on path. It clears when a blend completes, the motion of a pending instruction starts, or a motion instruction executes which causes a stop. Indicates not on path.
MovePendingQueueFullStatus
Sets when the instruction queue is full. It clears when the queue has room to hold another new coordinated move instruction.
TransformSourceStatus
The coordinate system is the source of an active transform.
TransformTargetStatus
The coordinate system is the target of an active transform.
CoorMotionLockStatus
Set when an axis lock is requested for an MCLM or MCCM instruction and the axis has crossed the Lock Position. Cleared when an MCLM or MCCM is initiated.
For the enumerations Immediate Forward Only and Immediate Reverse Only, the bit is set immediately when the MCLM or MCCM is initiated.
When the enumeration is Position Forward Only or Position Reverse Only, the bit is set when the Master Axis crosses the Lock Position in the specified direction. The bit is never set if the enumeration is NONE.
The CoordMotionLockStatus bit is cleared when the Master Axis reverses direction and the Slave Coordinate System stops following the Master Axis. The CoordMotionLockStatus bit is set again when the Slave Coordinate System resumes following the Master Axis. The CoordMotionLockStatus bit is also cleared when an MCS is initiated.
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