www.pudn.com > ucosii_for_m128_template.rar > os_time.c, change:2003-04-02,size:10081b
/* ********************************************************************************************************* * uC/OS-II * The Real-Time Kernel * TIME MANAGEMENT * * (c) Copyright 1992-2003, Jean J. Labrosse, Weston, FL * All Rights Reserved * * File : OS_TIME.C * By : Jean J. Labrosse ********************************************************************************************************* */ #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) { #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */ OS_CPU_SR cpu_sr; #endif INT8U y; 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 (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); } /* 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 MUST NOT call this function to resume a * task that is waiting for an event with timeout. This situation would make the task look * like a timeout occurred (unless you desire this effect). 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 ********************************************************************************************************* */ #if OS_TIME_DLY_RESUME_EN > 0 INT8U OSTimeDlyResume (INT8U prio) { #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */ OS_CPU_SR cpu_sr; #endif OS_TCB *ptcb; if (prio >= OS_LOWEST_PRIO) { return (OS_PRIO_INVALID); } OS_ENTER_CRITICAL(); ptcb = (OS_TCB *)OSTCBPrioTbl[prio]; /* Make sure that task exist */ if (ptcb != (OS_TCB *)0) { if (ptcb->OSTCBDly != 0) { /* See if task is delayed */ ptcb->OSTCBDly = 0; /* Clear the time delay */ if ((ptcb->OSTCBStat & OS_STAT_SUSPEND) == OS_STAT_RDY) { /* See if task is ready to run */ OSRdyGrp |= ptcb->OSTCBBitY; /* Make task ready to run */ 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); } else { OS_EXIT_CRITICAL(); return (OS_TIME_NOT_DLY); /* Indicate that task was not delayed */ } } OS_EXIT_CRITICAL(); return (OS_TASK_NOT_EXIST); /* The task does not exist */ } #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) { #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */ OS_CPU_SR cpu_sr; #endif INT32U ticks; 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; #endif OS_ENTER_CRITICAL(); OSTime = ticks; OS_EXIT_CRITICAL(); } #endif