dio.c

《嵌入式系统构件》源代码

/*
*********************************************************************************************************
*                                   Embedded Systems Building Blocks
*                                Complete and Ready-to-Use Modules in C
*
*                                         Discrete I/O Module
*
*                            (c) Copyright 1999, Jean J. Labrosse, Weston, FL
*                                          All Rights Reserved
*
* Filename   : DIO.C
* Programmer : Jean J. Labrosse
*********************************************************************************************************
*/

/*
*********************************************************************************************************
*                                           INCLUDE FILES
*********************************************************************************************************
*/

#define  DIO_GLOBALS
#include "includes.h"

/*
*********************************************************************************************************
*                                          LOCAL VARIABLES
*********************************************************************************************************
*/

static  OS_STK      DIOTaskStk[DIO_TASK_STK_SIZE];

/*
*********************************************************************************************************
*                                      LOCAL FUNCTION PROTOTYPES
*********************************************************************************************************
*/


static  void        DIIsTrig(DIO_DI *pdi);

static  void        DIOTask(void *data);

static  void        DIUpdate(void);

static  BOOLEAN     DOIsBlinkEn(DIO_DO *pdo);
static  void        DOUpdate(void);

/*$PAGE*/
/*
*********************************************************************************************************
*                               CONFIGURE DISCRETE INPUT EDGE DETECTION
*
* Description : This function is used to configure the edge detection capability of the discrete input
*               channel.
* Arguments   : n     is the discrete input channel to configure (0..DIO_MAX_DI-1).
*               fnct  is a pointer to a function that will be executed if the desired edge has been
*                     detected.
*               arg   is a pointer to arguments that are passed to the function called.
* Returns     : None.
*********************************************************************************************************
*/

#if  DI_EDGE_EN
void  DICfgEdgeDetectFnct (INT8U n, void (*fnct)(void *), void *arg)
{
    DIO_DI  *pdi;


    if (n < DIO_MAX_DI) {
        pdi                = &DITbl[n];
        OS_ENTER_CRITICAL();
        pdi->DITrigFnct    = fnct;
        pdi->DITrigFnctArg = arg;
        OS_EXIT_CRITICAL();
    }
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
*                                   CONFIGURE DISCRETE INPUT MODE
*
* Description : This function is used to configure the mode of a discrete input channel.
* Arguments   : n     is the discrete input channel to configure (0..DIO_MAX_DI-1).
*               mode  is the desired mode and can be:
*                     DI_MODE_LOW               input is forced LOW
*                     DI_MODE_HIGH              input is forced HIGH
*                     DI_MODE_DIRECT            input is based on state of physical sensor (default)
*                     DI_MODE_INV               input is based on the complement of physical sensor
*                     DI_MODE_EDGE_LOW_GOING    a LOW-going  transition is detected
*                     DI_MODE_EDGE_HIGH_GOING   a HIGH-going transition is detected
*                     DI_MODE_EDGE_BOTH         both a LOW-going and a HIGH-going transition are detected
*                     DI_MODE_TOGGLE_LOW_GOING  a LOW-going  transition is detected in toggle mode
*                     DI_MODE_TOGGLE_HIGH_GOING a HIGH-going transition is detected in toggle mode
* Returns     : None.
* Notes       : Edge detection is only available if the configuration constant DI_EDGE_EN is set to 1.
*********************************************************************************************************
*/

void  DICfgMode (INT8U n, INT8U mode)
{
    if (n < DIO_MAX_DI) {
        OS_ENTER_CRITICAL();
        DITbl[n].DIModeSel = mode;
        OS_EXIT_CRITICAL();
    }
}
/*$PAGE*/
/*
*********************************************************************************************************
*                                     CLEAR A DISCRETE INPUT CHANNEL
*
* Description : This function clears the number of edges detected if the discrete input channel is
*               configured to count edges.
* Arguments   : n     is the discrete input channel (0..DIO_MAX_DI-1) to clear.
* Returns     : none
*********************************************************************************************************
*/

#if  DI_EDGE_EN
void  DIClr (INT8U n)
{
    DIO_DI  *pdi;


    if (n < DIO_MAX_DI) {
        pdi = &DITbl[n];
        OS_ENTER_CRITICAL();
        if (pdi->DIModeSel == DI_MODE_EDGE_LOW_GOING  ||        /* See if edge detection mode selected */
            pdi->DIModeSel == DI_MODE_EDGE_HIGH_GOING ||
            pdi->DIModeSel == DI_MODE_EDGE_BOTH) {
            pdi->DIVal = 0;                                     /* Clear the number of edges detected  */
        }
        OS_EXIT_CRITICAL();
    }
}
#endif

/*$PAGE*/
/*
*********************************************************************************************************
*                                GET THE STATE OF A DISCRETE INPUT CHANNEL
*
* Description : This function is used to get the current state of a discrete input channel.  If the input
*               mode is set to one of the edge detection modes, the number of edges detected is returned.
* Arguments   : n     is the discrete input channel (0..DIO_MAX_DI-1).
* Returns     : 0     if the discrete input is negated  or, if an edge has not been detected
*               1     if the discrete input is asserted
*               > 0   if edges have been detected
*********************************************************************************************************
*/

INT16U  DIGet (INT8U n)
{
    INT16U  val;


    if (n < DIO_MAX_DI) {
        OS_ENTER_CRITICAL();
        val = DITbl[n].DIVal;                              /* Get state of DI channel                  */
        OS_EXIT_CRITICAL();
        return (val);
    } else {
        return (0);                                        /* Return negated for invalid channel       */
    }
}

/*$PAGE*/
/*
*********************************************************************************************************
*                                         DETECT EDGE ON INPUT
*
* Description : This function is called to detect an edge (low-going, high-going or both) on the selected
*               discrete input.
* Arguments   : pdi    is a pointer to the discrete input data structure.
* Returns     : none
*********************************************************************************************************
*/

#if DI_EDGE_EN
static  void  DIIsTrig (DIO_DI *pdi)
{
    BOOLEAN  trig;


    trig = FALSE;
    switch (pdi->DIModeSel) {
        case DI_MODE_EDGE_LOW_GOING:                       /* Negative going edge                      */
             if (pdi->DIPrev == 1 && pdi->DIIn == 0) {
                 trig = TRUE;
             }
             break;

        case DI_MODE_EDGE_HIGH_GOING:                      /* Positive going edge                      */
             if (pdi->DIPrev == 0 && pdi->DIIn == 1) {
                 trig = TRUE;
             }
             break;

        case DI_MODE_EDGE_BOTH:                            /* Both positive and negative going         */
             if ((pdi->DIPrev == 1 && pdi->DIIn == 0) ||
                 (pdi->DIPrev == 0 && pdi->DIIn == 1)) {
                 trig = TRUE;
             }
             break;
    }
    if (trig == TRUE) {                                    /* See if edge detected                     */
        if (pdi->DITrigFnct != NULL) {                     /* Yes, see used defined a function         */
            (*pdi->DITrigFnct)(pdi->DITrigFnctArg);        /* Yes, execute the user function           */
        }
        if (pdi->DIVal < 255) {                            /* Increment number of edges counted        */
            pdi->DIVal++;
        }
    }
    pdi->DIPrev = pdi->DIIn;                               /* Memorize previous input state            */
}
#endif

/*$PAGE*/
/*$PAGE*/
/*
*********************************************************************************************************
*                                    UPDATE DISCRETE IN CHANNELS
*
* Description : This function processes all of the discrete input channels.
* Arguments   : None.
* Returns     : None.
*********************************************************************************************************
*/

static  void  DIUpdate (void)
{
    INT8U    i;
    DIO_DI  *pdi;


    pdi = &DITbl[0];
    for (i = 0; i < DIO_MAX_DI; i++) {
        if (pdi->DIBypassEn == FALSE) {          /* See if discrete input channel is bypassed          */
            switch (pdi->DIModeSel) {            /* No, process channel                                */
                case DI_MODE_LOW:                /* Input is forced low                                */
                     pdi->DIVal = 0;
                     break;

                case DI_MODE_HIGH:               /* Input is forced high                               */
                     pdi->DIVal = 1;
                     break;

                case DI_MODE_DIRECT:                  /* Input is based on state of physical input     */
                     pdi->DIVal = (INT8U)pdi->DIIn;   /* Obtain the state of the sensor                */
                     break;

                case DI_MODE_INV:                /* Input is based on the complement state of input    */
                     pdi->DIVal = (INT8U)(pdi->DIIn ? 0 : 1);
                     break;

#if DI_EDGE_EN
                case DI_MODE_EDGE_LOW_GOING:
                case DI_MODE_EDGE_HIGH_GOING:
                case DI_MODE_EDGE_BOTH:
                     DIIsTrig(pdi);              /* Handle edge triggered mode                         */
                     break;
#endif
/*$PAGE*/
                case DI_MODE_TOGGLE_LOW_GOING:
                     if (pdi->DIPrev == 1 && pdi->DIIn == 0) {
                         pdi->DIVal = pdi->DIVal ? 0 : 1;
                     }
                     pdi->DIPrev = pdi->DIIn;