McePosTableUpdateLoadIndex

0.5.0

PosTable

Update the PosTable LoadIndex.

Version history

0.5.0

12 Nov 2025 deGroot

Changes

Changed:

rename NR_OF_INSTANCES to POSTABLE_CMDS_UBOUND for consistency

show full history

0.4.1

06 Jun 2025 Rioual

Changes

Added:

rename NR_OF_INSTANCES in INSTANCES_UBOUND (only relevant for Siemens)

0.4.0

15 May 2024 Rioual

Changes

Added:

conditions input

0.3.0

28 Mar 2024 Rioual

Changes

Added:

If the next valid entry has conditions, the current entry is a standstill

0.2.0

29 Feb 2024 Rioual

Changes

Changed:

Replace posTableMode by allowQueuing
Replace nQAmax by QA_MAX as a constant

0.1.0-beta

09 Feb 2024 Rioual

Changes

Added:

initial version

Overview

kind	name	type	comment
input	allowQueuing	`BOOL`	allow queuing the next motions
input	firstMove	`BOOL`	calc first move after system was reset
input	stopAfterLastEntry	`BOOL`	continue to the start of PosTable when searching for the next Index and LoadIndex
input	index	`INT`	PosTable index for current motion
input	conditions	`ARRAY [0..GVL.CONDITIONS_UBOUND] OF BOOL`	bits used as start conditions for a PosTable entry
in_out	posTable	`McePosTableData`	trajectory to be processed by PosTable
in_out	QA	`INT`	allowed Queueing Amount; number of motions to queue (for smooth motion)
in_out	loadIndex	`INT`	PosTable index for loading next motion(s)

Details

allowQueuing

BOOL

Allow queuing the next motions.

value	explanation
0	`QA` is decreased at the end of each motion until `0`
1	`QA` is updated depending on the number of remaining entries until standstill

firstMove

BOOL

Must be True when calculating the first motion of the PosTable.

False otherwise.

stopAfterLastEntry

BOOL

Continue to the start of PosTable when searching for the next Index and LoadIndex if False.

index

INT

The PosTable index to update the LoadIndex from.

conditions

ARRAY [0..GVL.CONDITIONS_UBOUND] OF BOOL

Bits used as start conditions for a PosTable entry.

If a PosTable entry has one or more bits in startConditions set to TRUE then the motion for that entry will not be started until the start conditions are satisfied.

Conditions are only checked for the TRUE state
If you need a condition to be checked for the FALSE state, you need to invert the connected signal outside of PosTable

posTable

McePosTableData

Trajectory to be processed by PosTable.

QA

INT

The Queueing Amount is the number of motions allowed to be queued.

Queueing motion in advance is necessary for smooth motion.

loadIndex

INT

Index of the last pre-loaded motion.

It is calculated as follow:

LoadIndex := Index + QA;

Source code

Declarations

(*Update the PosTable LoadIndex; for sending next motion*)
FUNCTION McePosTableUpdateLoadIndex

(*
 * -----------------------------------------------------------------------------
 * Name               : McePosTableUpdateLoadIndex
 * Version            : 0.5.0
 * Date               : 2025-11-12
 * Author             : deGroot
 * Family             : YaskawaMce
 * Organisation       : github.com/YaskawaEurope/mlx-examples
 * 
 * -----------------------------------------------------------------------------
 * Update the PosTable LoadIndex; for sending next motion
 * -----------------------------------------------------------------------------
 *)

VAR_INPUT
  allowQueuing : BOOL; (*allow queuing the next motions*)
  firstMove : BOOL; (*calc first move after system was reset*)
  stopAfterLastEntry : BOOL; (*continue to the start of PosTable when searching for the next Index and LoadIndex*)
  index : INT; (*PosTable index for current motion*)
  conditions : ARRAY [0..GVL.CONDITIONS_UBOUND] OF BOOL; (*bits used as start conditions for a PosTable entry*)
END_VAR

VAR_IN_OUT
  posTable : McePosTableData; (*trajectory to be processed by PosTable*)
  QA : INT; (*allowed Queueing Amount; number of motions to queue (for smooth motion)*)
  loadIndex : INT; (*PosTable index for loading next motion(s)*)
END_VAR

VAR
  nPosTableSize : INT; (*number of entries*)
  nEntriesRemaining : INT; (*number of entries remaining*)
END_VAR

VAR CONSTANT
  QA_MAX : INT := LIMIT(1, GVL.POSTABLE_CMDS_UBOUND, 20); (*max Queueing Amount; max number of motions which can be queued*)
END_VAR

Logic

nPosTableSize := UINT_TO_INT(SIZEOF(PosTable) / SIZEOF(PosTable.stEntry[0]));

// -----------------------------------------------------------------------------
// calculate loadIndex
// -----------------------------------------------------------------------------

// -------------------------------------
// not using queueing
// -------------------------------------
IF (QA = 0) OR firstMove THEN
  loadIndex := index;

// -------------------------------------
// using queueing
// -------------------------------------
ELSE
  // update load index to the next valid PosTableEntry
  loadIndex := McePosTableFindEntry(loadIndex, 1, nPosTableSize, TRUE, posTable);

  // no valid result found
  IF (loadIndex < 0) THEN
    loadIndex := index;
  END_IF;
END_IF;

// -----------------------------------------------------------------------------
// calculating QA in case of firstMove
// -----------------------------------------------------------------------------
IF firstMove AND allowQueuing THEN
  // -------------------------------------
  // calculate remaining entries until standstill
  // -------------------------------------
  nEntriesRemaining := McePosTableRemainingEntries( index := index,
                                                    loadIndex := loadIndex,
                                                    posTableSize := nPosTableSize,
                                                    rollOver := NOT stopAfterLastEntry,
                                                    conditions := conditions,
                                                    posTable := posTable);

  // -------------------------------------
  // calculate Queueing Amount (allowed number of motions to be queued)
  // -------------------------------------
  QA := nEntriesRemaining;

  IF (nEntriesRemaining > QA_MAX) THEN
    QA := QA_MAX;
  END_IF;

  IF QA < 0 THEN
    QA := 0;
  END_IF;
END_IF;

Implementation

Snippet of the function call:

McePosTableUpdateLoadIndex(
  allowQueuing := , 
  firstMove := , 
  stopAfterLastEntry := , 
  index := , 
  conditions := , 
  posTable := , 
  QA := , 
  loadIndex := );