同事遇到的难题，大家看看（上代码了，keil软仿真）。。。

#include <rtx51tny.h> /* RTX-51 tiny functions & defines */



/******************************************************************************/

/* Task 0 'job0': RTX-51 tiny starts execution with task 0 */

/******************************************************************************/

job0 () _task_ 0 { 

os_create_task (1); /* start task 1 */

os_create_task (2); /* start task 2 */

os_create_task (3); /* start task 3 */

os_create_task (4); /* start task 4 */



while (1) { /* endless loop */

if(keyA==PUSHED){

os_create_task (1); /* start task 1 */

os_delete_task (2); /* stop task 2 */

os_delete_task (3); /* stop task 3 */

os_delete_task (4); /* stop task 4 */

} 

if(keyB==PUSHED){

os_delete_task (1); /* stop task 1 */

os_create_task (2); /* start task 2 */

os_delete_task (3); /* stop task 3 */

os_delete_task (4); /* stop task 4 */

} 

if(keyC==PUSHED){

os_delete_task (1); /* stop task 1 */

os_delete_task (2); /* stop task 2 */

os_create_task (3); /* start task 3 */

os_delete_task (4); /* stop task 4 */

} 

if(keyD==PUSHED){

os_delete_task (1); /* stop task 1 */

os_delete_task (2); /* stop task 2 */

os_delete_task (3); /* stop task 3 */

os_create_task (4); /* start task 4 */

} 

os_wait (K_TMO, 5, 0); /* wait for timeout: 5 ticks */

}

}



/******************************************************************************/

/* Task 1 'job1': RTX-51 tiny starts this task with os_create_task (1) */

/******************************************************************************/

job1 () _task_ 1 {

while (1) { /* endless loop */

os_wait (K_TMO, 100, 0); /* wait for timeout: 100 ticks = 1s */

toogle_light(1);

os_wait (K_TMO, 200, 0); /* wait for timeout: 200 ticks = 2s */

toogle_light(2);

os_wait (K_TMO, 300, 0); /* wait for timeout: 300 ticks = 3s */

toogle_light(3);

}

}



/******************************************************************************/

/* Task 2 'job2': RTX-51 tiny starts this task with os_create_task (2) */

/******************************************************************************/

job2 () _task_ 2 {

while (1) { /* endless loop */

os_wait (K_TMO, 600, 0); /* wait for timeout: 100 ticks = 1s */

toogle_light(4);

os_wait (K_TMO, 100, 0); /* wait for timeout: 200 ticks = 2s */

toogle_light(5);

os_wait (K_TMO, 200, 0); /* wait for timeout: 300 ticks = 3s */

toogle_light(6);

}

}



/******************************************************************************/

/* Task 3 'job3': RTX-51 tiny starts this task with os_create_task (3) */

/******************************************************************************/

job3 () _task_ 3 {

while (1) { /* endless loop */

os_wait (K_TMO, 100, 0); /* wait for timeout: 100 ticks = 1s */

toogle_light(7);

os_wait (K_TMO, 200, 0); /* wait for timeout: 200 ticks = 2s */

toogle_light(8);

os_wait (K_TMO, 300, 0); /* wait for timeout: 300 ticks = 3s */

toogle_light(9);

}

}



/******************************************************************************/

/* Task 4 'job4': RTX-51 tiny starts this task with os_create_task (3) */

/******************************************************************************/

job3 () _task_ 4 {

while (1) { /* endless loop */

os_wait (K_TMO, 600, 0); /* wait for timeout: 600 ticks = 6s */

toogle_light(10);

os_wait (K_TMO, 800, 0); /* wait for timeout: 800 ticks = 8s */

toogle_light(11);

os_wait (K_TMO, 1200, 0); /* wait for timeout: 1200 ticks = 12s */

toogle_light(12);

}

}

// 全局条件.

int gflag = 0;



// 一个特殊的延时函数.这里先用状态参数.以后考虑使用回调函数

// 每个函数必须使用此函数延时!!

bool delay(int i, int delay)

{

        for(int d = 0; d < delay; d++)

                if(gflag != i)

                        return false;

        return true;

}



#define TASK1 1

void task1()

{

        bool bRet;



        // 做第一件事

        bRet = delay(TASK1, 6000);

        if (!bRet)        return;



        // 做第二件事

        bRet = delay((TASK1, 2000);

        if (!bRet)        return;

        // 做第三件事....

}

int _tmain(int argc, _TCHAR* argv[])

{

        while(1)

        {

                switch (gflag)

                {

                case TASK1:

                task1();

                        break;

                }

        }

        return 0;

}