BOOLEAN OSTmrStart (OS_TMR *ptmr,
INT8U *perr)
{
#ifdef OS_SAFETY_CRITICAL
if (perr == (INT8U *)0) {
OS_SAFETY_CRITICAL_EXCEPTION();
return (OS_FALSE);
}
#endif
#if OS_ARG_CHK_EN > 0u
if (ptmr == (OS_TMR *)0) {
*perr = OS_ERR_TMR_INVALID;
return (OS_FALSE);
}
#endif
if (ptmr->OSTmrType != OS_TMR_TYPE) { /* Validate timer structure */
*perr = OS_ERR_TMR_INVALID_TYPE;
return (OS_FALSE);
}
if (OSIntNesting > 0u) { /* See if trying to call from an ISR */
*perr = OS_ERR_TMR_ISR;
return (OS_FALSE);
}
OSSchedLock();
switch (ptmr->OSTmrState) {
case OS_TMR_STATE_RUNNING: /* Restart the timer */
OSTmr_Unlink(ptmr); /* ... Stop the timer */
OSTmr_Link(ptmr, OS_TMR_LINK_DLY); /* ... Link timer to timer wheel */
OSSchedUnlock();
*perr = OS_ERR_NONE;
return (OS_TRUE);
case OS_TMR_STATE_STOPPED: /* Start the timer */
case OS_TMR_STATE_COMPLETED:
OSTmr_Link(ptmr, OS_TMR_LINK_DLY); /* ... Link timer to timer wheel */
OSSchedUnlock();
*perr = OS_ERR_NONE;
return (OS_TRUE);
case OS_TMR_STATE_UNUSED: /* Timer not created */
OSSchedUnlock();
*perr = OS_ERR_TMR_INACTIVE;
return (OS_FALSE);
default:
OSSchedUnlock();
*perr = OS_ERR_TMR_INVALID_STATE;
return (OS_FALSE);
}
}
static void OSTmr_Task (void *p_arg)
{
INT8U err;
OS_TMR *ptmr;
OS_TMR *ptmr_next;
OS_TMR_CALLBACK pfnct;
OS_TMR_WHEEL *pspoke;
INT16U spoke;
p_arg = p_arg; /* Prevent compiler warning for not using 'p_arg' */
for (;;) {
/* 等待OSTmrSignal()发送的定时器更新的信号，在OSTimeTickHook()中调用，发送频率100HZ */
OSSemPend(OSTmrSemSignal, 0u, &err); /* Wait for signal indicating time to update timers */
/* 关调度 */
OSSchedLock();
OSTmrTime++; /* Increment the current time */
/* 获得当前要处理的分组编号 */
spoke = (INT16U)(OSTmrTime % OS_TMR_CFG_WHEEL_SIZE); /* Position on current timer wheel entry */
/* 获得当前要处理分组链表头 */
pspoke = &OSTmrWheelTbl[spoke];
/* 获得当前分组中第一个定时器控制块指针 */
ptmr = pspoke->OSTmrFirst;
while (ptmr != (OS_TMR *)0) {
/* 获得该组中下一个定时器控制块指针 */
ptmr_next = (OS_TMR *)ptmr->OSTmrNext; /* Point to next timer to update because current ... */
/* ... timer could get unlinked from the wheel. */
/* 定时器时间到 */
if (OSTmrTime == ptmr->OSTmrMatch) { /* Process each timer that expires */
/* 把定时器从当前分组移除，并设置定时器状态为OS_TMR_STATE_STOPPED
* 虽然定时器已经不在该定时器分组中了，但是该定时器仍然有效，可以通过定时器控制块访问
*/
OSTmr_Unlink(ptmr); /* Remove from current wheel spoke */
/* 如果是周期定时器,则更新定时器到时时间后，把定时器重新链接到新的分组 */
if (ptmr->OSTmrOpt == OS_TMR_OPT_PERIODIC) {
OSTmr_Link(ptmr, OS_TMR_LINK_PERIODIC); /* Recalculate new position of timer in wheel */
}
/* 如果是单次定时器，则在定时器控制块中标示定时器已经完成 */
else {
ptmr->OSTmrState = OS_TMR_STATE_COMPLETED; /* Indicate that the timer has completed */
}
/* 调用定时器到时回调函数 */
pfnct = ptmr->OSTmrCallback; /* Execute callback function if available */
if (pfnct != (OS_TMR_CALLBACK)0) {
(*pfnct)((void *)ptmr, ptmr->OSTmrCallbackArg);
}
}
/* 处理该分组中的下一个元素 */
ptmr = ptmr_next;
}
/* 允许调度 */
OSSchedUnlock();
}
}
static void OSTmr_Task( void *p_arg )
{
INT8U err;
OS_TMR *ptmr;
OS_TMR *ptmr_next;
OS_TMR_CALLBACK pfnct;
OS_TMR_WHEEL *pspoke;
INT16U spoke;
( void ) p_arg; /* Not using 'p_arg', prevent compiler warning */
for ( ;; )
{
OSSemPend( OSTmrSemSignal, 0, &err ); /* Wait for signal indicating time to update timers */
OSTmr_Lock( );
OSTmrTime++; /* Increment the current time */
spoke = OSTmrTime % OS_TMR_CFG_WHEEL_SIZE; /* Position on current timer wheel entry */
pspoke = &OSTmrWheelTbl[spoke];
ptmr = pspoke->OSTmrFirst;
while ( ptmr != ( OS_TMR * ) 0 )
{
ptmr_next = ptmr->OSTmrNext; /* Point to next timer to update because current ... */
/* ... timer could get unlinked from the wheel. */
if ( OSTmrTime == ptmr->OSTmrMatch )
{ /* Process each timer that expires */
pfnct = ptmr->OSTmrCallback; /* Execute callback function if available */
if ( pfnct != ( OS_TMR_CALLBACK ) 0 )
{
( *pfnct ) ( ptmr, ptmr->OSTmrCallbackArg );
}
OSTmr_Unlink( ptmr ); /* Remove from current wheel spoke */
if ( ptmr->OSTmrOpt == OS_TMR_OPT_PERIODIC )
{
OSTmr_Link( ptmr, OS_TMR_LINK_PERIODIC ); /* Recalculate new position of timer in wheel */
}
else
{
ptmr->OSTmrState = OS_TMR_STATE_COMPLETED; /* Indicate that the timer has completed */
}
}
ptmr = ptmr_next;
}
OSTmr_Unlock( );
}
}
BOOLEAN OSTmrStart (OS_TMR *ptmr,
INT8U *perr)
{
#ifdef OS_SAFETY_CRITICAL
if (perr == (INT8U *)0) {
OS_SAFETY_CRITICAL_EXCEPTION();
return (OS_FALSE);
}
#endif
#if OS_ARG_CHK_EN > 0u
if (ptmr == (OS_TMR *)0) {
*perr = OS_ERR_TMR_INVALID;
return (OS_FALSE);
}
#endif
if (ptmr->OSTmrType != OS_TMR_TYPE) { /* Validate timer structure */
*perr = OS_ERR_TMR_INVALID_TYPE;
return (OS_FALSE);
}
if (OSIntNesting > 0u) { /* See if trying to call from an ISR */
*perr = OS_ERR_TMR_ISR;
return (OS_FALSE);
}
/* 调度器加锁 */
OSSchedLock();
switch (ptmr->OSTmrState) {
/* 如果当前定时器是正在运行状态，则把定时器从当前分组移除
* 更新定时器到时时间后，把定时器重新链接到新的分组，并设置为第一次开始计时
*/
case OS_TMR_STATE_RUNNING: /* Restart the timer */
OSTmr_Unlink(ptmr); /* ... Stop the timer */
/* 使用OS_TMR_LINK_DLY选项把定时器链接进新的分组
* 会按照第一次插入定时器，设置Dly或者Period
*/
OSTmr_Link(ptmr, OS_TMR_LINK_DLY); /* ... Link timer to timer wheel */
OSSchedUnlock();
*perr = OS_ERR_NONE;
return (OS_TRUE);
/* 如果定时器是Stop状态或者单次定时器的COMPLETED状态
* 则按照第一次插入定时器，设置Dly或者Period
*/
case OS_TMR_STATE_STOPPED: /* Start the timer */
case OS_TMR_STATE_COMPLETED:
OSTmr_Link(ptmr, OS_TMR_LINK_DLY); /* ... Link timer to timer wheel */
OSSchedUnlock();
*perr = OS_ERR_NONE;
return (OS_TRUE);
/* 如果定时器是未使用状态，返回错误信息 */
case OS_TMR_STATE_UNUSED: /* Timer not created */
OSSchedUnlock();
*perr = OS_ERR_TMR_INACTIVE;
return (OS_FALSE);
default:
OSSchedUnlock();
*perr = OS_ERR_TMR_INVALID_STATE;
return (OS_FALSE);
}
}
