How to enable a callback for cyclic IO - data

Caution: using that callback routine can have a massiv influence to the realtime behavior of the stack!

This feature is unavailable for multicore projects until GOAL v2.23.0.

The example below shows the use of the callback function:

create the following local prototype and variables
Add the callback function to the callback handler

/****************************************************************************/
/* Local Prototypes */
/****************************************************************************/
static GOAL_STATUS_T appl_pnioCb(
    GOAL_PNIO_T *pHdlPnio,                      /**< PROFINET instance */
    GOAL_PNIO_CB_ID_T id,                       /**< callback id */
    GOAL_PNIO_CB_DATA_T *pCb                    /**< callback parameters */
);


/****************************************************************************/
/* Local Variables */
/****************************************************************************/
static GOAL_BOOL_T flgAppReady = GOAL_FALSE;    /**< app ready flag */
static GOAL_PNIO_AR_ID_T idAr = 0;              /**< AR ID */
static GOAL_PNIO_T *pPnio;                      /**< PROFINET instance */
static char targetData[APPL_MOD_SIZE];          /**< dummy where data is copied to */


/****************************************************************************/
/** Profinet Callback Handler
 *
 * This function collects all callbacks from the stack and decides if the
 * callback must be handled.
 */
static GOAL_STATUS_T appl_pnioCb(
    GOAL_PNIO_T *pHdlPnio,                      /**< PROFINET instance */
    GOAL_PNIO_CB_ID_T id,                       /**< callback id */
    GOAL_PNIO_CB_DATA_T *pCb                    /**< callback parameters */
)
{
    GOAL_STATUS_T res = GOAL_OK;                /* return value */

    UNUSEDARG(pHdlPnio);

    /* handle callback IDs */
    switch (id) {

        case GOAL_PNIO_CB_ID_APPL_READY:
            /* application ready was confirmed, start data handling if not
             * already running */
            if (GOAL_TRUE != flgAppReady) {
                flgAppReady = GOAL_TRUE;
                idAr = pCb->data[0].idAr;
            }
            break;

        case GOAL_PNIO_CB_ID_RELEASE_AR:
            /* AR was released, stop data handling if it was the first AR */
            if (idAr == pCb->data[0].idAr) {
                flgAppReady = GOAL_FALSE;
                idAr = 0;
            }
            break;

        case GOAL_PNIO_CB_ID_BLINK:
            goal_targetSetLeds((pCb->data[1].stateDcpLight) ? UINT32_MAX : 0);
            break;

        case GOAL_PNIO_CB_ID_NEW_IO_DATA:
        	/* New I/O data received.
        	 * Be careful: this call will block the PNIO stack
        	 * so just do the copying here and nothing else.
        	 * If not fast enough, just set a flag and retrieve the data
        	 * later in appl_loop if required.
        	 **/
        	memcpy(targetData, pCb->data[2].pCu8, pCb->data[1].u16);
        	break;
        default:
            break;
    }

    return res;
}

To use the cb function GOAL_PNIO_CB_ID_NEW_IO_DATA the following functions have to be called exactly in the order described below before and after function goal_pnioNew(...):

goal_pnioCfgNewIoDataCbSet(GOAL_TRUE); → configure stack to feature the GOAL_PNIO_CB_ID_NEW_IO_DATA callback
goal_pnioCyclicCtrl(pPnio,GOAL_TRUE); → enable GOAL_PNIO_CB_ID_NEW_IO_DATA callback for each arrived cyclic frame

/****************************************************************************/
/** Application Setup
 *
 * Setup the application.
 */
GOAL_STATUS_T appl_setup(
    void
)
{
    GOAL_STATUS_T res;                          /* result */
     
    /* configure stack to feature the GOAL_PNIO_CB_ID_NEW_IO_DATA callback */
    goal_pnioCfgNewIoDataCbSet(GOAL_TRUE);

    /* create new PROFINET instance */
    res = goal_pnioNew(&pPnio, APPL_PNIO_ID, appl_pnioCb);
    if (GOAL_RES_ERR(res)) {
        goal_logErr("failed to create a new PROFINET instance");
        return res;
    }
    
    /* enable GOAL_PNIO_CB_ID_NEW_IO_DATA callback for each arrived cyclic frame */
    goal_pnioCyclicCtrl(pPnio,GOAL_TRUE);

    goal_logInfo("Initializing device structure");

    /* from here create the device configuration */
      ...

    /* PROFINET configuration succesful */
    goal_logInfo("PROFINET ready");

    return GOAL_OK;
}