if (PC_GetKey(&key)) {                             /* See if key has been pressed              */
            if (key == 0x1B) {                             /* Yes, see if it's the ESCAPE key          */
                PC_DOSReturn();                            /* Yes, return to DOS                       */
            }
        }
        
        OSTimeDly(OS_TICKS_PER_SEC);                       /* Wait one second                          */
    }
}
/*$PAGE*/
/*
*********************************************************************************************************
*                                               TASK #1
*
* Description: This task executes every 100 mS and measures the time it task to perform stack checking
*              for each of the 5 application tasks.  Also, this task displays the statistics related to
*              each task's stack usage.
*********************************************************************************************************
*/

void  Task1 (void *pdata)
{
    INT8U       err;
    OS_STK_DATA data;                       /* Storage for task stack data                             */
    INT16U      time;                       /* Execution time (in uS)                                  */
    INT8U       i;
    char        s[80];


    pdata = pdata;
    for (;;) {
        for (i = 0; i < 7; i++) {
            PC_ElapsedStart();
            err  = OSTaskStkChk(TASK_START_PRIO+i, &data);
            time = PC_ElapsedStop();
            if (err == OS_NO_ERR) {
                sprintf(s, "%3ld         %3ld         %3ld         %5d",
                        data.OSFree + data.OSUsed,
                        data.OSFree,
                        data.OSUsed,
                        time);
                PC_DispStr(19, 12+i, s, DISP_FGND_YELLOW);
            }
        }
        OSTimeDlyHMSM(0, 0, 0, 100);                       /* Delay for 100 mS                         */
    }
}
/*$PAGE*/
/*
*********************************************************************************************************
*                                               TASK #2
*
* Description: This task displays a clockwise rotating wheel on the screen.
*********************************************************************************************************
*/

void  Task2 (void *data)
{
    data = data;
    for (;;) {
        PC_DispChar(70, 15, '|',  DISP_FGND_WHITE + DISP_BGND_RED);
        OSTimeDly(10);
        PC_DispChar(70, 15, '/',  DISP_FGND_WHITE + DISP_BGND_RED);
        OSTimeDly(10);
        PC_DispChar(70, 15, '-',  DISP_FGND_WHITE + DISP_BGND_RED);
        OSTimeDly(10);
        PC_DispChar(70, 15, '\\', DISP_FGND_WHITE + DISP_BGND_RED);
        OSTimeDly(10);
    }
}
/*$PAGE*/
/*
*********************************************************************************************************
*                                               TASK #3
*
* Description: This task displays a counter-clockwise rotating wheel on the screen.
*
* Note(s)    : I allocated 100 bytes of storage on the stack to artificially 'eat' up stack space.
*********************************************************************************************************
*/

void  Task3 (void *data)
{
    char    dummy[500];
    INT16U  i;

    
    data = data;
    for (i = 0; i < 499; i++) {        /* Use up the stack with 'junk'                                 */
        dummy[i] = '?';
    }
    for (;;) {
        PC_DispChar(70, 16, '|',  DISP_FGND_WHITE + DISP_BGND_BLUE);
        OSTimeDly(20);
        PC_DispChar(70, 16, '\\', DISP_FGND_WHITE + DISP_BGND_BLUE);
        OSTimeDly(20);
        PC_DispChar(70, 16, '-',  DISP_FGND_WHITE + DISP_BGND_BLUE);
        OSTimeDly(20);
        PC_DispChar(70, 16, '/',  DISP_FGND_WHITE + DISP_BGND_BLUE);
        OSTimeDly(20);
    }
}
/*$PAGE*/
/*
*********************************************************************************************************
*                                               TASK #4
*
* Description: This task sends a message to Task #5.  The message consist of a character that needs to
*              be displayed by Task #5.  This task then waits for an acknowledgement from Task #5
*              indicating that the message has been displayed.
*********************************************************************************************************
*/

void  Task4 (void *data)
{
    char   txmsg;
    INT8U  err;
    
    
    data  = data;
    txmsg = 'A';
    for (;;) {
        while (txmsg <= 'Z') {
            OSMboxPost(TxMbox, (void *)&txmsg);  /* Send message to Task #5                            */
            OSMboxPend(AckMbox, 0, &err);        /* Wait for acknowledgement from Task #5              */
            txmsg++;                             /* Next message to send                               */
        }
        txmsg = 'A';                             /* Start new series of messages                       */
    }
}
/*$PAGE*/
/*
*********************************************************************************************************
*                                               TASK #5
*
* Description: This task displays messages sent by Task #4.  When the message is displayed, Task #5
*              acknowledges Task #4.
*********************************************************************************************************
*/

void  Task5 (void *data)
{
    char  *rxmsg;
    INT8U  err;
    
    
    data = data;
    for (;;) {
        rxmsg = (char *)OSMboxPend(TxMbox, 0, &err);                  /* Wait for message from Task #4 */
        PC_DispChar(70, 18, *rxmsg, DISP_FGND_YELLOW + DISP_BGND_RED);
        OSTimeDlyHMSM(0, 0, 1, 0);                                    /* Wait 1 second                 */
        OSMboxPost(AckMbox, (void *)1);                               /* Acknowledge reception of msg  */
    }
}
/*$PAGE*/
/*
*********************************************************************************************************
*                                               CLOCK TASK
*********************************************************************************************************
*/

void  TaskClk (void *data)
{
    struct time now;
    struct date today;
    char        s[40];


    data = data;
    for (;;) {
        PC_GetDateTime(s);
        PC_DispStr(0, 24, s, DISP_FGND_BLUE + DISP_BGND_CYAN);
        OSTimeDly(OS_TICKS_PER_SEC);
    }
}