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📄 os_core.lst

📁 基于51单片机UCOS移植
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 835   1      
 836   1      
 837   1          OSTCBList     = (OS_TCB *)0;                                 /* TCB Initialization                    
             -   */
 838   1          for (i = 0; i < (OS_LOWEST_PRIO + 1); i++) {                 /* Clear the priority table              
             -   */
 839   2              OSTCBPrioTbl[i] = (OS_TCB *)0;
 840   2          }
 841   1          ptcb1 = &OSTCBTbl[0];
 842   1          ptcb2 = &OSTCBTbl[1];
 843   1          for (i = 0; i < (OS_MAX_TASKS + OS_N_SYS_TASKS - 1); i++) {  /* Init. list of free TCBs               
             -   */
 844   2              ptcb1->OSTCBNext = ptcb2;
 845   2              ptcb1++;
 846   2              ptcb2++;
 847   2          }
 848   1          ptcb1->OSTCBNext = (OS_TCB *)0;                              /* Last OS_TCB                           
             -   */
 849   1          OSTCBFreeList    = &OSTCBTbl[0];
 850   1      }
 851          /*$PAGE*/
 852          /*
 853          *********************************************************************************************************
 854          *                                              SCHEDULER
 855          *
 856          * Description: This function is called by other uC/OS-II services to determine whether a new, high
 857          *              priority task has been made ready to run.  This function is invoked by TASK level code
 858          *              and is not used to reschedule tasks from ISRs (see OSIntExit() for ISR rescheduling).
 859          *
 860          * Arguments  : none
 861          *
 862          * Returns    : none
 863          *
 864          * Notes      : 1) This function is INTERNAL to uC/OS-II and your application should not call it.
 865          *              2) Rescheduling is prevented when the scheduler is locked (see OS_SchedLock())
 866          *********************************************************************************************************
C51 COMPILER V9.01   OS_CORE                                                               10/31/2012 17:19:07 PAGE 16  

 867          */
 868          
 869          void  OS_Sched (void)
 870          {
 871   1      #if OS_CRITICAL_METHOD == 3                            /* Allocate storage for CPU status register     */
                  OS_CPU_SR  cpu_sr;
              #endif    
 874   1          INT8U      y;
 875   1      
 876   1      
 877   1          OS_ENTER_CRITICAL();
 878   1          if ((OSIntNesting == 0) && (OSLockNesting == 0)) { /* Sched. only if all ISRs done & not locked    */
 879   2              y             = OSUnMapTbl[OSRdyGrp];          /* Get pointer to HPT ready to run              */
 880   2              OSPrioHighRdy = (INT8U)((y << 3) + OSUnMapTbl[OSRdyTbl[y]]);
 881   2              if (OSPrioHighRdy != OSPrioCur) {              /* No Ctx Sw if current task is highest rdy     */
 882   3                  OSTCBHighRdy = OSTCBPrioTbl[OSPrioHighRdy];
 883   3                  OSCtxSwCtr++;                              /* Increment context switch counter             */
 884   3                  OS_TASK_SW();                              /* Perform a context switch                     */
 885   3              }
 886   2          }
 887   1          OS_EXIT_CRITICAL();
 888   1      }
 889          /*$PAGE*/
 890          /*
 891          *********************************************************************************************************
 892          *                                              IDLE TASK
 893          *
 894          * Description: This task is internal to uC/OS-II and executes whenever no other higher priority tasks
 895          *              executes because they are ALL waiting for event(s) to occur.
 896          *
 897          * Arguments  : none
 898          *
 899          * Returns    : none
 900          *
 901          * Note(s)    : 1) OSTaskIdleHook() is called after the critical section to ensure that interrupts will be
 902          *                 enabled for at least a few instructions.  On some processors (ex. Philips XA), enabling
 903          *                 and then disabling interrupts didn't allow the processor enough time to have interrupts
 904          *                 enabled before they were disabled again.  uC/OS-II would thus never recognize
 905          *                 interrupts.
 906          *              2) This hook has been added to allow you to do such things as STOP the CPU to conserve 
 907          *                 power.
 908          *********************************************************************************************************
 909          */
 910          
 911          void  OS_TaskIdle (void *ppdata)
 912          {
 913   1      #if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */
                  OS_CPU_SR  cpu_sr;
              #endif    
 916   1          
 917   1          
 918   1          ppdata = ppdata;                               /* Prevent compiler warning for not using 'pdata'     *
             -/
 919   1          for (;;) {
 920   2              OS_ENTER_CRITICAL();
 921   2              OSIdleCtr++;
 922   2              OS_EXIT_CRITICAL();
 923   2              OSTaskIdleHook();                        /* Call user definable HOOK                           */
 924   2          }
 925   1      }
 926          /*$PAGE*/
 927          /*
C51 COMPILER V9.01   OS_CORE                                                               10/31/2012 17:19:07 PAGE 17  

 928          *********************************************************************************************************
 929          *                                            STATISTICS TASK
 930          *
 931          * Description: This task is internal to uC/OS-II and is used to compute some statistics about the
 932          *              multitasking environment.  Specifically, OS_TaskStat() computes the CPU usage.
 933          *              CPU usage is determined by:
 934          *
 935          *                                          OSIdleCtr
 936          *                 OSCPUUsage = 100 * (1 - ------------)     (units are in %)
 937          *                                         OSIdleCtrMax
 938          *
 939          * Arguments  : pdata     this pointer is not used at this time.
 940          *
 941          * Returns    : none
 942          *
 943          * Notes      : 1) This task runs at a priority level higher than the idle task.  In fact, it runs at the
 944          *                 next higher priority, OS_IDLE_PRIO-1.
 945          *              2) You can disable this task by setting the configuration #define OS_TASK_STAT_EN to 0.
 946          *              3) We delay for 5 seconds in the beginning to allow the system to reach steady state and
 947          *                 have all other tasks created before we do statistics.  You MUST have at least a delay
 948          *                 of 2 seconds to allow for the system to establish the maximum value for the idle
 949          *                 counter.
 950          *********************************************************************************************************
 951          */
 952          
 953          #if OS_TASK_STAT_EN > 0
              void  OS_TaskStat (void *ppdata)
              {
              #if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */
                  OS_CPU_SR  cpu_sr;
              #endif    
                  INT32U     run;
                  INT32U     max;
                  INT8S      usage;
              
              
                  ppdata = ppdata;                               /* Prevent compiler warning for not using 'pdata'     *
             -/
                  while (OSStatRdy == FALSE) {
                      OSTimeDly(2 * OS_TICKS_PER_SEC);         /* Wait until statistic task is ready                 */
                  }
                  max = OSIdleCtrMax / 100L;
                  for (;;) {
                      OS_ENTER_CRITICAL();
                      OSIdleCtrRun = OSIdleCtr;                /* Obtain the of the idle counter for the past second */
                      run          = OSIdleCtr;
                      OSIdleCtr    = 0L;                       /* Reset the idle counter for the next second         */
                      OS_EXIT_CRITICAL();
                      if (max > 0L) {
                          usage = (INT8S)(100L - run / max);
                          if (usage >= 0) {                    /* Make sure we don't have a negative percentage      */
                              OSCPUUsage = usage;
                          } else {
                              OSCPUUsage = 0;
                          }
                      } else {
                          OSCPUUsage = 0;
                          max        = OSIdleCtrMax / 100L;
                      }
                      OSTaskStatHook();                        /* Invoke user definable hook                         */
                      OSTimeDly(OS_TICKS_PER_SEC);             /* Accumulate OSIdleCtr for the next second           */
                  }
C51 COMPILER V9.01   OS_CORE                                                               10/31/2012 17:19:07 PAGE 18  

              }
              #endif
 991          /*$PAGE*/
 992          /*
 993          *********************************************************************************************************
 994          *                                            INITIALIZE TCB
 995          *
 996          * Description: This function is internal to uC/OS-II and is used to initialize a Task Control Block when
 997          *              a task is created (see OSTaskCreate() and OSTaskCreateExt()).
 998          *
 999          * Arguments  : prio          is the priority of the task being created
1000          *
1001          *              ptos          is a pointer to the task's top-of-stack assuming that the CPU registers
1002          *                            have been placed on the stack.  Note that the top-of-stack corresponds to a
1003          *                            'high' memory location is OS_STK_GROWTH is set to 1 and a 'low' memory
1004          *                            location if OS_STK_GROWTH is set to 0.  Note that stack growth is CPU
1005          *                            specific.
1006          *
1007          *              pbos          is a pointer to the bottom of stack.  A NULL pointer is passed if called by
1008          *                            'OSTaskCreate()'.
1009          *
1010          *              id            is the task's ID (0..65535)
1011          *
1012          *              stk_size      is the size of the stack (in 'stack units').  If the stack units are INT8Us
1013          *                            then, 'stk_size' contains the number of bytes for the stack.  If the stack
1014          *                            units are INT32Us then, the stack contains '4 * stk_size' bytes.  The stack
1015          *                            units are established by the #define constant OS_STK which is CPU
1016          *                            specific.  'stk_size' is 0 if called by 'OSTaskCreate()'.
1017          *
1018          *              pext          is a pointer to a user supplied memory area that is used to extend the task
1019          *                            control block.  This allows you to store the contents of floating-point
1020          *                            registers, MMU registers or anything else you could find useful during a
1021          *                            context switch.  You can even assign a name to each task and store this name
1022          *                            in this TCB extension.  A NULL pointer is passed if called by OSTaskCreate().
1023          *
1024          *              opt           options as passed to 'OSTaskCreateExt()' or,
1025          *                            0 if called from 'OSTaskCreate()'.
1026          *
1027          * Returns    : OS_NO_ERR         if the call was successful
1028          *              OS_NO_MORE_TCB    if there are no more free TCBs to be allocated and thus, the task cannot
1029          *                                be created.
1030          *
1031          * Note       : This function is INTERNAL to uC/OS-II and your application should not call it.
1032          *********************************************************************************************************
1033          */
1034          
1035          INT8U  OS_TCBInit (INT8U prio, OS_STK *ptos, OS_STK *pbos, INT16U id, INT32U stk_size, void *pext, INT16U 
             -opt)
1036          {
1037   1      #if OS_CRITICAL_METHOD == 3                                /* Allocate storage for CPU status register */
                  OS_CPU_SR  cpu_sr;
              #endif    
1040   1          OS_TCB    *ptcb;
1041   1      
1042   1      
1043   1          OS_ENTER_CRITICAL();
1044   1          ptcb = OSTCBFreeList;                                  /* Get a free TCB from the free TCB list    */
1045   1          if (ptcb != (OS_TCB *)0) {
1046   2              OSTCBFreeList        = ptcb->OSTCBNext;            /* Update pointer to free TCB list          */
1047   2              OS_EXIT_CRITICAL();
1048   2              ptcb->OSTCBStkPtr    = ptos;                       /* Load Stack pointer in TCB                */
1049   2              ptcb->OSTCBPrio      = (INT8U)prio;                /* Load task priority into TCB              */
C51 COMPILER V9.01   OS_CORE                                                               10/31/2012 17:19:07 PAGE 19  

1050   2              ptcb->OSTCBStat      = OS_STAT_R

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