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MPI Application Template
template.c
 

ptappend.c -- Simple motion path generation, using position/time points with Motion Append
/* ptappend.c */

/* Copyright(c) 1991-2006 by Motion Engineering, Inc.  All rights reserved.
 *
 * This software  contains proprietary and  confidential information  of
 * Motion Engineering Inc., and its suppliers.  Except as may be set forth
 * in the license agreement under which  this software is supplied, use,
 * disclosure, or  reproduction is prohibited without the prior express
 * written consent of Motion Engineering, Inc.
 */

/*

:Simple motion path generation, using position/time points with Motion Append

This sample code demonstrates the motion type, MPIMotionTypePT, with Motion
 Append.  A simple trapezoidal velocity profile points list is created, and
 downloaded to the controller.  The time delta between each position is
 constant and the positions are spaced to generate an acceleration, constant
 velocity, and deceleration profile to the final position.

Several motion parameters must be initialized for the PT motion type:

 params.pt.pointCount - Specifies the number of points (position/time).

 params.pt.position - Pointer to a position[...] array.  There is one
    position value per point, per axis.  The length of the array must be
    equal to pointCount multiplied by the number of axes.  The positions
    are interleaved in the array by the axis index.

    For example, a three axis system would have:
        position[0] = position for axis 0
        position[1] = position for axis 1
        position[2] = position for axis 2
        position[3] = position for axis 0
        position[4] = position for axis 1
        etc.

 params.pt.time - Pointer to a time[...] array.  There is one time value
    per point.  The time specifies the number of seconds between the previous 
    position (point) and the specified position.  The length of the 
    time array must be equal to the pointCount.

 params.pt.point.retain - Specifies whether the MPI and XMP should buffer the
    points after they have executed.  If retain = 0, the buffer will destroy
    the points after they have executed.  If retain = 1, the buffer will keep the
    points after they have executed.  This parameter is useful for future backup
    on path capability.

 params.pt.point.final - Specifies if more points will be loaded.  If final = 1,
    no more points will be loaded.  If final = 0, more points can be loaded
    with mpiMotionModify(...) using the APPEND attribute.

 params.pt.point.emptyCount - Specifies how many points the XMP-Series
    controller must have in it's buffer.  If the XMP's point buffer falls
    below the emptyCount, an E-Stop event will be generated by the motion
    supervisor, decelerating all the associated axes to a stop.

When the points are passed to mpiMotionStart(...), the MPI calculates
 constant velocity segments to fit exactly through the specified positions at
 the specified times.  The MPI library automatically handles buffering points
 lists that are larger than the XMP's buffer.  Presently, the XMP-Series
 controller can store 128 Frames per axis.  Each point requires one Frame
 per axis.

Special Considerations:

It is not necesary to specify the initial command position as the first
 position point.  The time[...] values can be constant or vary for each point.
 Constant time[...] values make the programmer's calculations easier.  For
 optimum performance, the number of points can be reduced, with no loss of
 resolution, by replacing the constant velocity sections with longer
 time[...] values.

When creating points lists longer than 64 points, you must create an Event
 Manager.  The Event Manager handles point buffering between the MPI and the XMP
 controller.

For Acceleration/Jerk fits through a points list, use the motion type,
 MPIMotionTypePVT. In this case, position/velocity/time points are specified.


Warning!  This is a sample program to assist in the integration of an
 MEI motion controller with your application.  It may not contain all
 of the logic and safety features that your application requires.

*/

#include <stdlib.h>
#include <stdio.h>

#include "stdmpi.h"
#include "stdmei.h"

#include "apputil.h"

#if defined(ARG_MAIN_RENAME)
#define main    ptappendMain

argMainRENAME(main, ptappend)
#endif

#define AXIS_COUNT      (1)
#define POINT_COUNT     (36)    /* Number of points in trajectory */
#define TIME            (0.1)   /* Time between points (seconds) */
#define POSITION_DELTA  (10.0)  /* counts for each point */

double position[AXIS_COUNT * POINT_COUNT];
double time[POINT_COUNT];

double position2[AXIS_COUNT * POINT_COUNT];
double time2[POINT_COUNT];


/* Simple trapezoidal profile velocity path */
double point[POINT_COUNT + 1];

/* Command line arguments and defaults */
long    axisNumber[AXIS_COUNT] = { 0,  };
long    motionNumber = 0;

Arg argList[] = {
    {   "-axis",    ArgTypeLONG,    &axisNumber[0], },
    {   "-motion",  ArgTypeLONG,    &motionNumber,  },

    {   NULL,       ArgTypeINVALID, NULL,   }
};


int
    main(int    argc,
         char   *argv[])
{
    MPIControl      control;                /* Control object */
    MPIAxis         axis[MEIXmpMAX_Axes];   /* Array of axis objects */
    MPIMotion       motion;                 /* Motion object */
    MPINotify       notify;                 /* Event notification handle */
    MPIEventMgr     eventMgr;               /* Event manager handle */
    MPIMotionParams params;                 /* MPI motion parameters */
    MPIMotionParams params2;                    /* MPI motion parameters */


    Service         service;                /* Event manager service handle */

    long    returnValue;

    MPIControlType      controlType;
    MPIControlAddress   controlAddress;

    long    argIndex;
    long    pointIndex;
    long    axisIndex;
    MPI_BOOL    motionDone;

    MPIEventMask    eventMask;

    double  initialPosition[MEIXmpMAX_Axes];

    double pos = 0.0;


    /* Parse command line for Control type and address */
    argIndex =
        argControl(argc,
                   argv,
                   &controlType,
                   &controlAddress);

    /* Parse command line for application-specific arguments */
    while (argIndex < argc) {
        long    argIndexNew;

        argIndexNew = argSet(argList, argIndex, argc, argv);

        if (argIndexNew <= argIndex) {
            argIndex = argIndexNew;
            break;
        }
        else {
            argIndex = argIndexNew;
        }
    }

    /* Check for unknown/invalid command line arguments */
    if ((argIndex < argc) ||
        (axisNumber[0] > (MEIXmpMAX_Axes - AXIS_COUNT)) ||
        (motionNumber  >= MEIXmpMAX_MSs)) {
        meiPlatformConsole("usage: %s %s\n"
                           "\t\t[-axis # (0 .. %d)]\n"
                           "\t\t[-motion # (0 .. %d)]\n",
                            argv[0],
                            ArgUSAGE,
                            MEIXmpMAX_Axes - AXIS_COUNT,
                            MEIXmpMAX_MSs - 1);
        exit(MPIMessageARG_INVALID);
    }

    /* Obtain a Control handle */
    control =
        mpiControlCreate(controlType,
                         &controlAddress);
    msgCHECK(mpiControlValidate(control));

    /* Initialize the controller */
    returnValue = mpiControlInit(control);
    msgCHECK(returnValue);

    /* Create Axis objects */
    for (axisIndex = 0; axisIndex < AXIS_COUNT; axisIndex++) {
        axis[axisIndex] =
            mpiAxisCreate(control,
                          axisNumber[axisIndex]);
        msgCHECK(mpiAxisValidate(axis[axisIndex]));
    }

    /* Create motion object */
    motion =
        mpiMotionCreate(control,
                        motionNumber,
                        NULL);
    msgCHECK(mpiMotionValidate(motion));

    /* Append axis objects to motion object */
    for (axisIndex = 0; axisIndex < AXIS_COUNT; axisIndex++) {
        returnValue =
            mpiMotionAxisAppend(motion,
                                axis[axisIndex]);
        msgCHECK(returnValue);

        /* Read initial command position */
        returnValue =
            mpiAxisCommandPositionGet(axis[axisIndex],
                                      &initialPosition[axisIndex]);
        msgCHECK(returnValue);

    }

    /* Request notification of all events from motion */
    mpiEventMaskCLEAR(eventMask);
    mpiEventMaskALL(eventMask);
    returnValue =
        mpiMotionEventNotifySet(motion,
                                eventMask,
                                NULL);
    msgCHECK(returnValue);

    /* Create event notification object for motion */
    notify =
        mpiNotifyCreate(eventMask,
                        motion);
    msgCHECK(mpiNotifyValidate(notify));

    /* Create event manager object */
    eventMgr = mpiEventMgrCreate(control);
    msgCHECK(mpiEventMgrValidate(eventMgr));

    /* Add notify to event manager's list */
    returnValue =
        mpiEventMgrNotifyAppend(eventMgr,
                                notify);
    msgCHECK(returnValue);

    /* Create service thread */
    service =
        serviceCreate(eventMgr,
                      -1,   /* Default (max) priority */
                      -1);  /* Default sleep (msec) */
    meiAssert(service != NULL);

    /* Initialize motion params structure */
    params.pt.pointCount = POINT_COUNT;
    params.pt.position = position;
    params.pt.time = time;
    params.pt.point.retain = TRUE;      /* Flush frame buffer after execution */
    params.pt.point.final = 0;      /* Last point */
    params.pt.point.emptyCount = 2; /* Start E-Stop if frames left to execute
                                        is less than this limit. -1 disables */

    /* Initialize second motion params structure */
    params2.pt.pointCount = POINT_COUNT;
    params2.pt.position = position2;
    params2.pt.time = time2;
    params2.pt.point.retain = TRUE;     /* Flush frame buffer after execution */
    params2.pt.point.final = 1;     /* Last point */
    params2.pt.point.emptyCount = 5;    /* Start E-Stop if frames left to execute
                                        is less than this limit. -1 disables */

    for(pointIndex = 0; pointIndex < (POINT_COUNT + 1); pointIndex++)
    {
        point[pointIndex] = pos;
        pos += (double) POSITION_DELTA;
    }

    /* Create points */
    for (pointIndex = 0; pointIndex < POINT_COUNT; pointIndex++) {

        time[pointIndex] = TIME;    /* Delta time between points */

        for (axisIndex = 0; axisIndex < AXIS_COUNT; axisIndex++) {
            /* Position at point */
            position[(pointIndex * AXIS_COUNT) + axisIndex] =
                point[(pointIndex + 1)] + initialPosition[axisIndex];
        }
    }

    /* Create secondary points */
    for (pointIndex = 0; pointIndex < POINT_COUNT; pointIndex++) {

        time2[pointIndex] = TIME;   /* Delta time between points */

        for (axisIndex = 0; axisIndex < AXIS_COUNT; axisIndex++) {
            /* Position at point */
            position2[(pointIndex * AXIS_COUNT) + axisIndex] =
                (point[(pointIndex + 1)] + point[POINT_COUNT]) + initialPosition[axisIndex];
        }
    }

    /* Start motion */
    returnValue =
        mpiMotionStart(motion,
                       MPIMotionTypePT,
                       &params);
    fprintf(stderr,
        "mpiMotionStart returns 0x%x: %s\n",
        returnValue,
        mpiMessage(returnValue, NULL));
    msgCHECK(returnValue);

    /* Modify motion */
    returnValue =
        mpiMotionModify(motion,
                       MPIMotionTypePT | MPIMotionAttrMaskAPPEND,
                       &params2);
    fprintf(stderr,
        "mpiMotionModify returns 0x%x: %s\n",
        returnValue,
        mpiMessage(returnValue, NULL));
    msgCHECK(returnValue);

    /* Collect motion events */
    motionDone = FALSE;
    while (motionDone != TRUE) {

        MPIEventStatus  eventStatus;

        returnValue =
            mpiNotifyEventWait(notify,
                               &eventStatus,
                               MPIWaitFOREVER);

        switch(eventStatus.type) {

            case MPIEventTypeMOTION_DONE: {
                motionDone = TRUE;
                break;
            }
            default: {
                break;
            }
        }

        fprintf(stderr,
                "mpiNotifyEventWait() returns 0x%x\n"
                "\teventStatus: type %d source 0x%x info 0x%x\n",
                returnValue,
                eventStatus.type,
                eventStatus.source,
                eventStatus.info[0]);
        msgCHECK(returnValue);

    }

    /* Delete Objects */
    returnValue = serviceDelete(service);
    msgCHECK(returnValue);

    returnValue = mpiEventMgrDelete(eventMgr);
    msgCHECK(returnValue);

    returnValue = mpiNotifyDelete(notify);
    msgCHECK(returnValue);

    returnValue = mpiMotionDelete(motion);
    msgCHECK(returnValue);

    for (axisIndex = 0; axisIndex < AXIS_COUNT; axisIndex++) {
        returnValue = mpiAxisDelete(axis[axisIndex]);
        msgCHECK(returnValue);
    }

    returnValue = mpiControlDelete(control);
    msgCHECK(returnValue);

    return ((int)returnValue);
}


 
      
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