master.c

基于mc908gz60的LIN通信例程

/*******************************************************************************
*                (c) Freescale Inc. 2004  all rights reserved.                 *
*                                                                              *
*                                                                              *
*     An example application for AN2767 based on MC68HC908GZ60A,master node.   *
*     =====================================================================    *
*                                                                              *
*    $File Name     : master.c$                                                *
*    $Author        : re004c$                                                  *
*    $Date          : Nov-8-2004$                                             *
*    $Version       : 1.1.6.0$                                                 *
*    Function:                                                                 *
*                                                                              *
* ============================================================================ *
* THIS SOFTWARE IS PROVIDED BY FREESCALE SEMICONDUCTOR "AS IS" AND ANY         *
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED  *
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE       *
* DISCLAIMED.  IN NO EVENT SHALL FREESCALE SEMICONDUCTOR OR ITS CONTRIBUTORS   *
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR       *
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF         *
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS     *
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN      *
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)      *
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE   *
* POSSIBILITY OF SUCH DAMAGE.                                                  *
*******************************************************************************/

#include <lin.h>
#include "target.h"

unsigned char ErrCount;                                     /* errors counter */
unsigned char MsgCount;                                   /* messages counter */
unsigned int  Time;                            /* time from real time counter */

l_u8 messages [4];
unsigned char messages_counter = 1;
l_bool active_nodes [4] = {1,1,1,1};
l_u16 status;
l_bool sleep_mode = 0;

#define PERIODS_PER_SECOND  (200u)
#define EVER (;;)                                 /* to avoid warning message */

static l_u16  previous_start_time = 0;      /* Wraps around but usage is safe */


/*******************************************************************************
*                                                                              *
*    Function name: NodeFailure                                                *
*    Function:      Do the processing necessary to re-start or enter           *
*                   limp-home mode. In this example we enter an endless loop.  *
*                                                                              *
*******************************************************************************/

void NodeFailure (void)
{
    for EVER                                      /* to avoid warning message */
    {
        /* forever */
    }
}


/*******************************************************************************
*                                                                              *
*    Function name: BusyWaitUntilNextPeriod                                    *
*    Function:      Waits until it is time for the next processing call. Call  *
*                   this routine when you are done with all processing expected*
*                   for the present processing period. The first time might    *
*                   take some time (since start_time is uninitialized), but    *
*                   then it will run fine.                                     *
*******************************************************************************/

void BusyWaitUntilNextPeriod (void)
{
    l_u16         t_now;                    /* The time counter value for now */
    l_u16         elapsed;    /* Time elapsed since previous ideal start time */
    do
    {
        #ifdef PET_WATCHDOG
        PET_WATCHDOG();
        #endif
        
        t_now   = l_get_us_counter();
        elapsed = (l_u16) (t_now - previous_start_time);
    }
    while (elapsed < HW_DELAY);
    
    previous_start_time += HW_DELAY;
   /* This construct avoids time drift, previous_start_time = t_now, wouldn't */
}


/*******************************************************************************
*                                                                              *
*    Function name: Delay                                                      *
*    Function:      Simple delay routine. Delay for n ms.                      *
*                                                                              *
*******************************************************************************/

void Delay(unsigned int n)
{
    unsigned int stopTime = 30 * n;
    while (stopTime != 0) 
    {

    #ifdef PET_WATCHDOG
    PET_WATCHDOG();
    #endif
    
    stopTime--;
    }
}


/*******************************************************************************
*                                                                              *
*    Function name: NewNode                                                    *
*    Function:      Flash LEDs in sequence low to high.                        *
*                                                                              *
*******************************************************************************/

void NewNode()
{
    char i;
    unsigned char strip = 0x01;

    for (i = 0; i < 8; i++)
    {
        PTF = ~strip;
        Delay(125);
        strip = strip<<1;
    }
}


/*******************************************************************************
*                                                                              *
*    Function name: LostNode                                                   *
*    Function:      Flash LEDs in sequence low to high.                        *
*                                                                              *
*******************************************************************************/

void LostNode()
{
    char i;
    unsigned char strip = 0x80;

    for (i = 0; i < 8; i++)
    {
        PTF = ~strip;
        Delay(125);
        strip = strip>>1;
    }
}


/*******************************************************************************
*                                                                              *
*    Function name: GotoSleep                                                  *
*    Function:      Manage the goto the sleep transition.                      *
*                                                                              *
 ******************************************************************************/

void GotoSleep (void)
{
    while (l_sch_tick_i1() != 1)                                 /* one round */
    {
        BusyWaitUntilNextPeriod();
    }
    l_ifc_goto_sleep_i1();                         /* send the sleep commnand */
    sleep_mode = 1;                                /* set the sleep mode flag */
}


/*******************************************************************************
*                                                                              *
*    Function name: ChangeList                                                 *
*    Function:      Change the status of the active_nodes list.                *
*                                                                              *
 ******************************************************************************/
 
void ChangeList (l_bool value)
{
    unsigned char i;
    
    for (i = 0; i<4 ; i++)
    {
        active_nodes [i] = value;        /* change the active node list status*/
    }
}


/*******************************************************************************
*                                                                              *
*    Function name: LinActive                                                  *
*    Function:      Flashes LEDs if LIN is disabled.                           *
*                                                                              *
*******************************************************************************/

void LinActive()
{
                /* switch turned on and cluster not previously in sleep mode? */