os_cpu_c.c

UCOS-II在VC++6.0环境下的调试及编译

	OSPrioCur = OSPrioHighRdy;		//得到当前就绪任务最高优先级数
	sp = OSTCBHighRdy->OSTCBStkPtr;	//得到重新执行的任务的堆栈指针
	
	
	//恢复所有处理器的寄存器
	Context.Edi = *sp++;
	Context.Esi = *sp++;
	Context.Ebp = *sp++;
	Context.Esp = *sp++;		//此时上下文中得到的esp是不正确的
	Context.Ebx = *sp++;
	Context.Edx = *sp++;
	Context.Ecx = *sp++;
	Context.Eax = *sp++;
	Context.EFlags = *sp++; 
	Context.Eip = *sp++;
	
	Context.Esp = (unsigned long)sp;		//得到正确的esp
	
	SetThreadContext(mainhandle, &Context);	//保存主线程上下文
}

/*********************************************************************************************************
;                                            HANDLE TICK ISR
;
; Description:  此函数为时钟调度关键程序，通过timeSetEvent函数来产生时钟节拍，timeSetEvent将产生一个
				线程调用此函数，此函数将与主任务同步运行，应此并不是中断主程序才来运行此函数的
				但此函数将模拟中断的产生，如果发现中断处于关闭状态，则退出
;
; Arguments  : none
;
; Returns    : none
;
; Note(s)    :  此函数与中断函数最不同的是没有立即保存寄存器，而且不能用iret指令，所以OSIntCtxSw()实现也不一样
				它是要返回调用函数的
;*********************************************************************************************************/

void CALLBACK OSTickISR(unsigned int a,unsigned int b,unsigned long c,unsigned long d,unsigned long e)
{
	if(!FlagEn)
		return;	//如果当前中断被屏蔽则返回

	SuspendThread(mainhandle);		//中止主线程的运行，模拟中断产生.但没有保存寄存器
	GetThreadContext(mainhandle, &Context);	//得到主线程上下文，为切换任务做准备

	OSIntNesting++;
	if (OSIntNesting == 1) {
		OSTCBCur->OSTCBStkPtr = (OS_STK *)Context.Esp;	//保存当前esp
	}	
	OSTimeTick();		//ucos内部定时
	OSIntExit();		//由于不能使用中断返回指令，所以此函数是要返回的

	ResumeThread(mainhandle);	//模拟中断返回，主线程得以继续执行

}
/*$PAGE*/
#if OS_CPU_HOOKS_EN
/*
*********************************************************************************************************
*                                       OS INITIALIZATION HOOK
*                                            (BEGINNING)
*
* Description: This function is called by OSInit() at the beginning of OSInit().
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts should be disabled during this call.
*********************************************************************************************************
*/
#if OS_VERSION > 203
void OSInitHookBegin (void)
{
}
#endif

/*
*********************************************************************************************************
*                                       OS INITIALIZATION HOOK
*                                               (END)
*
* Description: This function is called by OSInit() at the end of OSInit().
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts should be disabled during this call.
*********************************************************************************************************
*/
#if OS_VERSION > 203
void OSInitHookEnd (void)
{
}
#endif


/*
*********************************************************************************************************
*                                          TASK CREATION HOOK
*
* Description: This function is called when a task is created.
*
* Arguments  : ptcb   is a pointer to the task control block of the task being created.
*
* Note(s)    : 1) Interrupts are disabled during this call.
*********************************************************************************************************
*/
void OSTaskCreateHook (OS_TCB *ptcb)
{
    ptcb = ptcb;                       /* Prevent compiler warning                                     */
}


/*
*********************************************************************************************************
*                                           TASK DELETION HOOK
*
* Description: This function is called when a task is deleted.
*
* Arguments  : ptcb   is a pointer to the task control block of the task being deleted.
*
* Note(s)    : 1) Interrupts are disabled during this call.
*********************************************************************************************************
*/
void OSTaskDelHook (OS_TCB *ptcb)
{
    ptcb = ptcb;                       /* Prevent compiler warning                                     */
}

/*
*********************************************************************************************************
*                                           TASK SWITCH HOOK
*
* Description: This function is called when a task switch is performed.  This allows you to perform other
*              operations during a context switch.
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts are disabled during this call.
*              2) It is assumed that the global pointer 'OSTCBHighRdy' points to the TCB of the task that
*                 will be 'switched in' (i.e. the highest priority task) and, 'OSTCBCur' points to the 
*                 task being switched out (i.e. the preempted task).
*********************************************************************************************************
*/
void OSTaskSwHook (void)
{
}

/*
*********************************************************************************************************
*                                           STATISTIC TASK HOOK
*
* Description: This function is called every second by uC/OS-II's statistics task.  This allows your 
*              application to add functionality to the statistics task.
*
* Arguments  : none
*********************************************************************************************************
*/
void OSTaskStatHook (void)
{
}

/*
*********************************************************************************************************
*                                           OSTCBInit() HOOK
*
* Description: This function is called by OSTCBInit() after setting up most of the TCB.
*
* Arguments  : ptcb    is a pointer to the TCB of the task being created.
*
* Note(s)    : 1) Interrupts may or may not be ENABLED during this call.
*********************************************************************************************************
*/
#if OS_VERSION > 203
void OSTCBInitHook (OS_TCB *ptcb)
{
    ptcb = ptcb;                                           /* Prevent Compiler warning                 */
}
#endif


/*
*********************************************************************************************************
*                                               TICK HOOK
*
* Description: This function is called every tick.打印定时信息
				changed by 文佳 Email：[e-mail]
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts may or may not be ENABLED during this call.
*********************************************************************************************************
*/
void OSTimeTickHook (void)
{

//	_log("   tasktick\n");

}


/*
*********************************************************************************************************
*                                             IDLE TASK HOOK
*
* Description: This function is called by the idle task.  This hook has been added to allow you to do  
*              such things as STOP the CPU to conserve power.changed by 文佳 Email：[e-mail]
*
* Arguments  : none 
*
* Note(s)    : 1) Interrupts are enabled during this call.
*********************************************************************************************************
*/
#if OS_VERSION >= 251
void OSTaskIdleHook (void)
{
	Sleep(1);		//这里一定要加上一个短短的延迟，要不会出现错误，
					//具体原因我也不太清楚，不过加上这个的好处是多的，
					//使得整个程序占有很少的cpu
}
#endif
#endif