void OSTimeTick (void)
{
#if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr;
#endif
OS_TCB *ptcb;
OSTimeTickHook(); /* Call user definable hook */
#if OS_TIME_GET_SET_EN > 0
OS_ENTER_CRITICAL(); /* Update the 32-bit tick counter */
OSTime++;
OS_EXIT_CRITICAL();
#endif
if (OSRunning == TRUE) {
ptcb = OSTCBList; /* Point at first TCB in TCB list */
while (ptcb->OSTCBPrio != OS_IDLE_PRIO) { /* Go through all TCBs in TCB list */
OS_ENTER_CRITICAL();
if (ptcb->OSTCBDly != 0) { /* Delayed or waiting for event with TO */
if (--ptcb->OSTCBDly == 0) { /* Decrement nbr of ticks to end of delay */
if ((ptcb->OSTCBStat & OS_STAT_SUSPEND) == OS_STAT_RDY) { /* Is task suspended? */
OSRdyGrp |= ptcb->OSTCBBitY; /* No, Make task R-to-R (timed out)*/
OSRdyTbl[ptcb->OSTCBY] |= ptcb->OSTCBBitX;
} else { /* Yes, Leave 1 tick to prevent ... */
ptcb->OSTCBDly = 1; /* ... loosing the task when the ... */
} /* ... suspension is removed. */
}
}
ptcb = ptcb->OSTCBNext; /* Point at next TCB in TCB list */
OS_EXIT_CRITICAL();
}
}
}
void OSTimeTick (void)
{
#if ((OS_CFG_TASK_TICK_EN == DEF_ENABLED) || (OS_CFG_TMR_EN == DEF_ENABLED))
OS_ERR err;
#endif
if (OSRunning != OS_STATE_OS_RUNNING) {
return;
}
OSTimeTickHook(); /* Call user definable hook */
#if (OS_CFG_TASK_TICK_EN == DEF_ENABLED)
(void)OSTaskSemPost(&OSTickTaskTCB, /* Signal tick task */
OS_OPT_POST_NONE,
&err);
#if (OS_CFG_SCHED_ROUND_ROBIN_EN == DEF_ENABLED)
OS_SchedRoundRobin(&OSRdyList[OSPrioCur]);
#endif
#if (OS_CFG_TMR_EN == DEF_ENABLED)
OSTmrUpdateCtr--;
if (OSTmrUpdateCtr == 0u) {
OSTmrUpdateCtr = OSTmrUpdateCnt;
(void)OSTaskSemPost(&OSTmrTaskTCB, /* Signal timer task */
OS_OPT_POST_NONE,
&err);
}
#endif
#endif
}
void OSTimeTick (void)
{
OS_ERR err;
#if OS_CFG_ISR_POST_DEFERRED_EN > 0u
CPU_TS ts;
#endif
OSTimeTickHook(); /* Call user definable hook */
#if OS_CFG_ISR_POST_DEFERRED_EN > 0u
ts = OS_TS_GET(); /* Get timestamp */
OS_IntQPost((OS_OBJ_TYPE) OS_OBJ_TYPE_TICK, /* Post to ISR queue */
(void *)&OSRdyList[OSPrioCur],
(void *) 0,
(OS_MSG_SIZE) 0u,
(OS_FLAGS ) 0u,
(OS_OPT ) 0u,
(CPU_TS ) ts,
(OS_ERR *)&err);
#else
(void)OSTaskSemPost((OS_TCB *)&OSTickTaskTCB, /* Signal tick task */
(OS_OPT ) OS_OPT_POST_NONE,
(OS_ERR *)&err);
#if OS_CFG_SCHED_ROUND_ROBIN_EN > 0u
OS_SchedRoundRobin(&OSRdyList[OSPrioCur]);
#endif
#if OS_CFG_TMR_EN > 0u
OSTmrUpdateCtr--;
if (OSTmrUpdateCtr == (OS_CTR)0u) {
OSTmrUpdateCtr = OSTmrUpdateCnt;
OSTaskSemPost((OS_TCB *)&OSTmrTaskTCB, /* Signal timer task */
(OS_OPT ) OS_OPT_POST_NONE,
(OS_ERR *)&err);
}
#endif
#endif
}
void OSTimeDynTick (OS_TICK ticks)
{
OS_ERR err;
CPU_SR_ALLOC();
if (OSRunning != OS_STATE_OS_RUNNING) {
return;
}
OSTimeTickHook();
CPU_CRITICAL_ENTER();
OSTickCtrPend += ticks;
CPU_CRITICAL_EXIT();
(void)OSTaskSemPost(&OSTickTaskTCB, /* Signal tick task */
OS_OPT_POST_NONE,
&err);
}
//时钟节拍函数 PROCESS SYSTEM TICK
//描述: uC/OS需要用户提供周期性信号源，用于实现时间延时和确认超时。节拍率应在每秒10次到100次
// 之间，或者说10到100Hz。时钟节拍率越高，系统的额外负荷就越重.时钟节拍的实际频率取决于
// 用户应用程序的精度。时钟节拍源可以是专门的硬件定时器，也可以是来自50/60Hz交流电源的
// 信号
//参数: 无
//返回: 无
void OSTimeTick (void)
{
#if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr;
#endif
OS_TCB *ptcb; //定义任务控制块优先级表变量
OSTimeTickHook(); //调用户·自定义函数(钩子函数)
#if OS_TIME_GET_SET_EN > 0
OS_ENTER_CRITICAL(); //累加从开机以来的时间，用的是一个无符号32位变量
OSTime++;
OS_EXIT_CRITICAL();
#endif
if (OSRunning == TRUE) {
ptcb = OSTCBList; //保存任务控制块列表首地址
//从OSTCBList开始，沿着OS_TCB链表做，一直做到空闲任务
while (ptcb->OSTCBPrio != OS_IDLE_PRIO) { /* Go through all TCBs in TCB list */
OS_ENTER_CRITICAL();
if (ptcb->OSTCBDly != 0) { //如果任务等待时的最多节拍数不为0
//而确切被任务挂起的函数OSTaskSuspend()挂起的任务则不会进入就绪态
//执行时间直接与应用程序中建立了多少个务成正比
if (--ptcb->OSTCBDly == 0) { //如果任务等待时的最多节拍数为0
//当某任务的任务控制块中的时间延时项OSTCBDly减到了零，这个任务就进入了就绪态
if ((ptcb->OSTCBStat & OS_STAT_SUSPEND) == OS_STAT_RDY) { /* Is task suspended? */
OSRdyGrp |= ptcb->OSTCBBitY; /* No, Make task R-to-R (timed out)*/
OSRdyTbl[ptcb->OSTCBY] |= ptcb->OSTCBBitX;
} else { /* Yes, Leave 1 tick to prevent ... */
ptcb->OSTCBDly = 1; /* ... loosing the task when the ... */
} /* ... suspension is removed. */
}
}
ptcb = ptcb->OSTCBNext; //指向任务块双向链接表的后链接
OS_EXIT_CRITICAL();
}
}
}