Absolute Positioning that ends with a velocity move using MC_MoveContinuousAbsolute

MC_MoveContinuousAbsolute will perform an absolute move and transition to a velocity move when absolute positioning is complete. The value in the input EndVelocity will be the final speed for the continuous speed portion of the movement. If the function block is executed again while performing a previous MC_MoveContinuousAbsolute operation, the changes in parameters will be applied.

  • When using ‘infinite running repeat position’, Direction = 2 for shortest distance can be used to have the function block select the direction for shortest move.

  • This function block will cause the axis to transition to ContinuousMotion state.

  • The sign of the EndVelocity value will determine the direction of the speed move portion.

  • A negative EndVelocity value will move in the reverse direction and a positive EndVelocity value will move in the forward direction.

  • LS_Connect, MC_Power, and MC_Home must be executed before this function block can be used.

  • The examples in this topic can be found in the XMC_SingleAxis_FBs.zip downloadable from Example Applications.

Element Name Element Type Description
Execute Input Edge detected request to execute the function block.
Axis Input/Output Axis reference variable. This can not be a constant.
ContinuousUpdate Input Specify the update setting of the input value. This is explained in section 6.1.5 of the XMC user manual.
Position Input Specify the target position for the absolute move portion.
EndVelocity Input Specify the speed of the continuous movement portion.
Velocity Input Specify the maximum speed of the move.
Acceleration Input Specify the acceleration of the move.
Deceleration Input Specify the deceleration of the move.
Jerk Input Specify the change rate of acceleration and deceleration.
Direction Input

Specify the direction of the move.

  • 0-Not specified

  • 1-Forward direction

  • 2-Shortest distance

  • 3-Reverse direction

  • 4-Current direction
BufferMode Input Specify the sequential operation setting. See Buffer Mode table below.
InEndVelocity Output Indicates the axis has transitioned to continuous speed movement.
Busy Output Indicates the function block is currently being executed.
Active Output Indicates the function block is controlling the axis.
CommandAborted Output Indicates the function block was aborted.
Error Output Indicates whether an error occurs or not.
ErrorID Output Error Identification number.

 

BufferMode Table

Sections 6.1.4 and 8.2.10 of the XMC user manual provide more information about buffer modes.

Value Buffer Mode Description
0 Aborting Abort previous command and execute the command immediately.
1 Buffered Execute the command after previous command is completed.
2 BlendingLow The new command is blended into a previously executed command using the lower velocity value when comparing the previous command and new command.
3 BlendingPrevious The new command is blended into a previous command using the velocity of the previous command.
4 BlendingNext The new command is blended into a previous command using the velocity from the new command.
5 BlendingHigh The new command is blended into a previous command using the higher velocity value when comparing the previous command and new command.

//Set axis reference

Axis1 := 1;

 

IF (_AX01_RDY) AND (_AX01_SV_ON) AND (_AX01_HOME_CMPL) THEN

//Example MC_MoveContinuousAbsolute fb

INST_MOVECONTINUOUSABSOLUTE(Execute:=Execute_MoveContAbs, Axis:=Axis1,

ContinuousUpdate:=0, Position:=INST_MOVECONTINUOUSABSOLUTE.Position,

EndVelocity:=INST_MOVECONTINUOUSABSOLUTE.EndVelocity, Velocity:=INST_MOVECONTINUOUSABSOLUTE.Velocity, Acceleration:=INST_MOVECONTINUOUSABSOLUTE.Acceleration, Deceleration:=INST_MOVECONTINUOUSABSOLUTE.Deceleration, Jerk:=INST_MOVECONTINUOUSABSOLUTE.Jerk,

Direction:=INST_MOVECONTINUOUSABSOLUTE.Direction, BufferMode:=0,

ErrorID=>INST_MOVECONTINUOUSABSOLUTE.ErrorID);

END_IF;

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LM513