?? os_time.c
字號:
/*
*********************************************************************************************************
* uC/OS-II
* The Real-Time Kernel
* TIME MANAGEMENT
*
* (c) Copyright 1992-2006, Jean J. Labrosse, Weston, FL
* All Rights Reserved
*
* File : OS_TIME.C
* By : Jean J. Labrosse
* Version : V2.83
*********************************************************************************************************
*/
#ifndef OS_MASTER_FILE
#include <ucos_ii.h>
#endif
/*
*********************************************************************************************************
* DELAY TASK 'n' TICKS (n from 0 to 65535)
*
* Description: This function is called to delay execution of the currently running task until the
* specified number of system ticks expires. This, of course, directly equates to delaying
* the current task for some time to expire. No delay will result If the specified delay is
* 0. If the specified delay is greater than 0 then, a context switch will result.
*
* Arguments : ticks is the time delay that the task will be suspended in number of clock 'ticks'.
* Note that by specifying 0, the task will not be delayed.
*
* Returns : none
*********************************************************************************************************
*/
void OSTimeDly (INT16U ticks)
{
INT8U y;
#if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr = 0;
#endif
if (ticks > 0) { /* 0 means no delay! */
OS_ENTER_CRITICAL();
y = OSTCBCur->OSTCBY; /* Delay current task */
OSRdyTbl[y] &= ~OSTCBCur->OSTCBBitX;
if (OSRdyTbl[y] == 0) {
OSRdyGrp &= ~OSTCBCur->OSTCBBitY;
}
OSTCBCur->OSTCBDly = ticks; /* Load ticks in TCB */
OS_EXIT_CRITICAL();
OS_Sched(); /* Find next task to run! */
}
}
/*$PAGE*/
/*
*********************************************************************************************************
* DELAY TASK FOR SPECIFIED TIME
*
* Description: This function is called to delay execution of the currently running task until some time
* expires. This call allows you to specify the delay time in HOURS, MINUTES, SECONDS and
* MILLISECONDS instead of ticks.
*
* Arguments : hours specifies the number of hours that the task will be delayed (max. is 255)
* minutes specifies the number of minutes (max. 59)
* seconds specifies the number of seconds (max. 59)
* milli specifies the number of milliseconds (max. 999)
*
* Returns : OS_NO_ERR
* OS_TIME_INVALID_MINUTES
* OS_TIME_INVALID_SECONDS
* OS_TIME_INVALID_MS
* OS_TIME_ZERO_DLY
*
* Note(s) : The resolution on the milliseconds depends on the tick rate. For example, you can't do
* a 10 mS delay if the ticker interrupts every 100 mS. In this case, the delay would be
* set to 0. The actual delay is rounded to the nearest tick.
*********************************************************************************************************
*/
#if OS_TIME_DLY_HMSM_EN > 0
INT8U OSTimeDlyHMSM (INT8U hours, INT8U minutes, INT8U seconds, INT16U milli)
{
INT32U ticks;
INT16U loops;
#if OS_ARG_CHK_EN > 0
if (hours == 0) {
if (minutes == 0) {
if (seconds == 0) {
if (milli == 0) {
return (OS_TIME_ZERO_DLY);
}
}
}
}
if (minutes > 59) {
return (OS_TIME_INVALID_MINUTES); /* Validate arguments to be within range */
}
if (seconds > 59) {
return (OS_TIME_INVALID_SECONDS);
}
if (milli > 999) {
return (OS_TIME_INVALID_MILLI);
}
#endif
/* Compute the total number of clock ticks required.. */
/* .. (rounded to the nearest tick) */
ticks = ((INT32U)hours * 3600L + (INT32U)minutes * 60L + (INT32U)seconds) * OS_TICKS_PER_SEC
+ OS_TICKS_PER_SEC * ((INT32U)milli + 500L / OS_TICKS_PER_SEC) / 1000L;
loops = (INT16U)(ticks / 65536L); /* Compute the integral number of 65536 tick delays */
ticks = ticks % 65536L; /* Obtain the fractional number of ticks */
OSTimeDly((INT16U)ticks);
while (loops > 0) {
OSTimeDly((INT16U)32768u);
OSTimeDly((INT16U)32768u);
loops--;
}
return (OS_NO_ERR);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
* RESUME A DELAYED TASK
*
* Description: This function is used resume a task that has been delayed through a call to either
* OSTimeDly() or OSTimeDlyHMSM(). Note that you can call this function to resume a
* task that is waiting for an event with timeout. This would make the task look
* like a timeout occurred.
*
* Also, you cannot resume a task that has called OSTimeDlyHMSM() with a combined time that
* exceeds 65535 clock ticks. In other words, if the clock tick runs at 100 Hz then, you will
* not be able to resume a delayed task that called OSTimeDlyHMSM(0, 10, 55, 350) or higher:
*
* (10 Minutes * 60 + 55 Seconds + 0.35) * 100 ticks/second.
*
* Arguments : prio specifies the priority of the task to resume
*
* Returns : OS_NO_ERR Task has been resumed
* OS_PRIO_INVALID if the priority you specify is higher that the maximum allowed
* (i.e. >= OS_LOWEST_PRIO)
* OS_TIME_NOT_DLY Task is not waiting for time to expire
* OS_TASK_NOT_EXIST The desired task has not been created or has been assigned to a Mutex.
*********************************************************************************************************
*/
#if OS_TIME_DLY_RESUME_EN > 0
INT8U OSTimeDlyResume (INT8U prio)
{
OS_TCB *ptcb;
#if OS_CRITICAL_METHOD == 3 /* Storage for CPU status register */
OS_CPU_SR cpu_sr = 0;
#endif
if (prio >= OS_LOWEST_PRIO) {
return (OS_PRIO_INVALID);
}
OS_ENTER_CRITICAL();
ptcb = OSTCBPrioTbl[prio]; /* Make sure that task exist */
if (ptcb == (OS_TCB *)0) {
OS_EXIT_CRITICAL();
return (OS_TASK_NOT_EXIST); /* The task does not exist */
}
if (ptcb == (OS_TCB *)1) {
OS_EXIT_CRITICAL();
return (OS_TASK_NOT_EXIST); /* The task does not exist */
}
if (ptcb->OSTCBDly == 0) { /* See if task is delayed */
OS_EXIT_CRITICAL();
return (OS_TIME_NOT_DLY); /* Indicate that task was not delayed */
}
ptcb->OSTCBDly = 0; /* Clear the time delay */
if ((ptcb->OSTCBStat & OS_STAT_PEND_ANY) != OS_STAT_RDY) {
ptcb->OSTCBStat &= ~OS_STAT_PEND_ANY; /* Yes, Clear status flag */
ptcb->OSTCBPendTO = OS_TRUE; /* Indicate PEND timeout */
} else {
ptcb->OSTCBPendTO = OS_FALSE;
}
if ((ptcb->OSTCBStat & OS_STAT_SUSPEND) == OS_STAT_RDY) { /* Is task suspended? */
OSRdyGrp |= ptcb->OSTCBBitY; /* No, Make ready */
OSRdyTbl[ptcb->OSTCBY] |= ptcb->OSTCBBitX;
OS_EXIT_CRITICAL();
OS_Sched(); /* See if this is new highest priority */
} else {
OS_EXIT_CRITICAL(); /* Task may be suspended */
}
return (OS_NO_ERR);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
* GET CURRENT SYSTEM TIME
*
* Description: This function is used by your application to obtain the current value of the 32-bit
* counter which keeps track of the number of clock ticks.
*
* Arguments : none
*
* Returns : The current value of OSTime
*********************************************************************************************************
*/
#if OS_TIME_GET_SET_EN > 0
INT32U OSTimeGet (void)
{
INT32U ticks;
#if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr = 0;
#endif
OS_ENTER_CRITICAL();
ticks = OSTime;
OS_EXIT_CRITICAL();
return (ticks);
}
#endif
/*
*********************************************************************************************************
* SET SYSTEM CLOCK
*
* Description: This function sets the 32-bit counter which keeps track of the number of clock ticks.
*
* Arguments : ticks specifies the new value that OSTime needs to take.
*
* Returns : none
*********************************************************************************************************
*/
#if OS_TIME_GET_SET_EN > 0
void OSTimeSet (INT32U ticks)
{
#if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr = 0;
#endif
OS_ENTER_CRITICAL();
OSTime = ticks;
OS_EXIT_CRITICAL();
}
#endif