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📄 os_sem.lst

📁 一个UC/OS的小应用
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 213          /*$PAGE*/
 214          /*
 215          *********************************************************************************************************
 216          *                                           PEND ON SEMAPHORE
 217          *
 218          * Description: This function waits for a semaphore.
 219          *
 220          * Arguments  : pevent        is a pointer to the event control block associated with the desired
 221          *                            semaphore.
 222          *
 223          *              timeout       is an optional timeout period (in clock ticks).  If non-zero, your task will
 224          *                            wait for the resource up to the amount of time specified by this argument.
 225          *                            If you specify 0, however, your task will wait forever at the specified
 226          *                            semaphore or, until the resource becomes available (or the event occurs).
 227          *
 228          *              err           is a pointer to where an error message will be deposited.  Possible error
 229          *                            messages are:
 230          *
 231          *                            OS_NO_ERR           The call was successful and your task owns the resource
 232          *                                                or, the event you are waiting for occurred.
 233          *                            OS_TIMEOUT          The semaphore was not received within the specified
 234          *                                                timeout.
 235          *                            OS_ERR_EVENT_TYPE   If you didn't pass a pointer to a semaphore.
 236          *                            OS_ERR_PEND_ISR     If you called this function from an ISR and the result
 237          *                                                would lead to a suspension.
 238          *                            OS_ERR_PEVENT_NULL  If 'pevent' is a NULL pointer.
 239          *
 240          * Returns    : none
C51 COMPILER V7.06   OS_SEM                                                                04/04/2006 15:07:22 PAGE 5   

 241          *********************************************************************************************************
 242          */
 243          
 244          void  OSSemPend (OS_EVENT *pevent, INT16U timeout, INT8U *err)LG_REENTRANT
 245          {
 246   1      #if OS_CRITICAL_METHOD == 3                           /* Allocate storage for CPU status register      */
                  OS_CPU_SR  cpu_sr;
              #endif    
 249   1      
 250   1      
 251   1          if (OSIntNesting > 0) {                           /* See if called from ISR ...                    */
 252   2              *err = OS_ERR_PEND_ISR;                       /* ... can't PEND from an ISR                    */
 253   2              return;
 254   2          }
 255   1      #if OS_ARG_CHK_EN > 0
 256   1          if (pevent == (OS_EVENT *)0) {                    /* Validate 'pevent'                             */
 257   2              *err = OS_ERR_PEVENT_NULL;
 258   2              return;
 259   2          }
 260   1          if (pevent->OSEventType != OS_EVENT_TYPE_SEM) {   /* Validate event block type                     */
 261   2              *err = OS_ERR_EVENT_TYPE;
 262   2              return;
 263   2          }
 264   1      #endif
 265   1          OS_ENTER_CRITICAL();
 266   1          if (pevent->OSEventCnt > 0) {                     /* If sem. is positive, resource available ...   */
 267   2              pevent->OSEventCnt--;                         /* ... decrement semaphore only if positive.     */
 268   2              OS_EXIT_CRITICAL();
 269   2              *err = OS_NO_ERR;
 270   2              return;
 271   2          }
 272   1                                                            /* Otherwise, must wait until event occurs       */
 273   1          OSTCBCur->OSTCBStat |= OS_STAT_SEM;               /* Resource not available, pend on semaphore     */
 274   1          OSTCBCur->OSTCBDly   = timeout;                   /* Store pend timeout in TCB                     */
 275   1          OS_EventTaskWait(pevent);                         /* Suspend task until event or timeout occurs    */
 276   1          OS_EXIT_CRITICAL();
 277   1          OS_Sched();                                       /* Find next highest priority task ready         */
 278   1          OS_ENTER_CRITICAL();
 279   1          if (OSTCBCur->OSTCBStat & OS_STAT_SEM) {          /* Must have timed out if still waiting for event*/
 280   2              OS_EventTO(pevent);
 281   2              OS_EXIT_CRITICAL();
 282   2              *err = OS_TIMEOUT;                            /* Indicate that didn't get event within TO      */
 283   2              return;
 284   2          }
 285   1          OSTCBCur->OSTCBEventPtr = (OS_EVENT *)0;
 286   1          OS_EXIT_CRITICAL();
 287   1          *err = OS_NO_ERR;
 288   1      }
 289          /*$PAGE*/
 290          /*
 291          *********************************************************************************************************
 292          *                                         POST TO A SEMAPHORE
 293          *
 294          * Description: This function signals a semaphore
 295          *
 296          * Arguments  : pevent        is a pointer to the event control block associated with the desired
 297          *                            semaphore.
 298          *
 299          * Returns    : OS_NO_ERR           The call was successful and the semaphore was signaled.
 300          *              OS_SEM_OVF          If the semaphore count exceeded its limit.  In other words, you have
 301          *                                  signalled the semaphore more often than you waited on it with either
 302          *                                  OSSemAccept() or OSSemPend().
C51 COMPILER V7.06   OS_SEM                                                                04/04/2006 15:07:22 PAGE 6   

 303          *              OS_ERR_EVENT_TYPE   If you didn't pass a pointer to a semaphore
 304          *              OS_ERR_PEVENT_NULL  If 'pevent' is a NULL pointer.
 305          *********************************************************************************************************
 306          */
 307          
 308          INT8U  OSSemPost (OS_EVENT *pevent)LG_REENTRANT
 309          {
 310   1      #if OS_CRITICAL_METHOD == 3                                /* Allocate storage for CPU status register */
                  OS_CPU_SR  cpu_sr;                               
              #endif    
 313   1      
 314   1      
 315   1      #if OS_ARG_CHK_EN > 0
 316   1          if (pevent == (OS_EVENT *)0) {                         /* Validate 'pevent'                        */
 317   2              return (OS_ERR_PEVENT_NULL);
 318   2          }
 319   1          if (pevent->OSEventType != OS_EVENT_TYPE_SEM) {        /* Validate event block type                */
 320   2              return (OS_ERR_EVENT_TYPE);
 321   2          }
 322   1      #endif
 323   1          OS_ENTER_CRITICAL();
 324   1          if (pevent->OSEventGrp != 0x00) {                      /* See if any task waiting for semaphore    */
 325   2              OS_EventTaskRdy(pevent, (void *)0, OS_STAT_SEM);   /* Ready highest prio task waiting on event */
 326   2              OS_EXIT_CRITICAL();
 327   2              OS_Sched();                                        /* Find highest priority task ready to run  */
 328   2              return (OS_NO_ERR);
 329   2          }
 330   1          if (pevent->OSEventCnt < 65535) {                 /* Make sure semaphore will not overflow         */
 331   2              pevent->OSEventCnt++;                         /* Increment semaphore count to register event   */
 332   2              OS_EXIT_CRITICAL();
 333   2              return (OS_NO_ERR);
 334   2          }
 335   1          OS_EXIT_CRITICAL();                               /* Semaphore value has reached its maximum       */
 336   1          return (OS_SEM_OVF);
 337   1      }
 338          /*$PAGE*/
 339          /*
 340          *********************************************************************************************************
 341          *                                          QUERY A SEMAPHORE
 342          *
 343          * Description: This function obtains information about a semaphore
 344          *
 345          * Arguments  : pevent        is a pointer to the event control block associated with the desired
 346          *                            semaphore
 347          *
 348          *              pdata         is a pointer to a structure that will contain information about the
 349          *                            semaphore.
 350          *
 351          * Returns    : OS_NO_ERR           The call was successful and the message was sent
 352          *              OS_ERR_EVENT_TYPE   If you are attempting to obtain data from a non semaphore.
 353          *              OS_ERR_PEVENT_NULL  If 'pevent' is a NULL pointer.
 354          *********************************************************************************************************
 355          */
 356          
 357          #if OS_SEM_QUERY_EN > 0
              INT8U  OSSemQuery (OS_EVENT *pevent, OS_SEM_DATA *os_pdata)LG_REENTRANT
              {
              #if OS_CRITICAL_METHOD == 3                                /* Allocate storage for CPU status register */
                  OS_CPU_SR  cpu_sr;
              #endif    
                  INT8U     *psrc;
                  INT8U     *pdest;
C51 COMPILER V7.06   OS_SEM                                                                04/04/2006 15:07:22 PAGE 7   

              
              
              #if OS_ARG_CHK_EN > 0
                  if (pevent == (OS_EVENT *)0) {                         /* Validate 'pevent'                        */
                      return (OS_ERR_PEVENT_NULL);
                  }
                  if (pevent->OSEventType != OS_EVENT_TYPE_SEM) {        /* Validate event block type                */
                      return (OS_ERR_EVENT_TYPE);
                  }
              #endif
                  OS_ENTER_CRITICAL();
                  os_pdata->OSEventGrp = pevent->OSEventGrp;                /* Copy message mailbox wait list           
             -*/
                  psrc              = &pevent->OSEventTbl[0];
                  pdest             = &os_pdata->OSEventTbl[0];
              #if OS_EVENT_TBL_SIZE > 0
                  *pdest++          = *psrc++;
              #endif
              
              #if OS_EVENT_TBL_SIZE > 1
                  *pdest++          = *psrc++;
              #endif
              
              #if OS_EVENT_TBL_SIZE > 2
                  *pdest++          = *psrc++;
              #endif
              
              #if OS_EVENT_TBL_SIZE > 3
                  *pdest++          = *psrc++;
              #endif
              
              #if OS_EVENT_TBL_SIZE > 4
                  *pdest++          = *psrc++;
              #endif
              
              #if OS_EVENT_TBL_SIZE > 5
                  *pdest++          = *psrc++;
              #endif
              
              #if OS_EVENT_TBL_SIZE > 6
                  *pdest++          = *psrc++;
              #endif
              
              #if OS_EVENT_TBL_SIZE > 7
                  *pdest            = *psrc;
              #endif
                  os_pdata->OSCnt      = pevent->OSEventCnt;                /* Get semaphore count                      
             -*/
                  OS_EXIT_CRITICAL();
                  return (OS_NO_ERR);
              }
              #endif                                                     /* OS_SEM_QUERY_EN                          */
 415          #endif                                                     /* OS_SEM_EN                                */


MODULE INFORMATION:   STATIC OVERLAYABLE
   CODE SIZE        =    826    ----
   CONSTANT SIZE    =   ----    ----
   XDATA SIZE       =   ----    ----
   PDATA SIZE       =   ----    ----
   DATA SIZE        =   ----    ----
   IDATA SIZE       =   ----    ----
C51 COMPILER V7.06   OS_SEM                                                                04/04/2006 15:07:22 PAGE 8   

   BIT SIZE         =   ----    ----
END OF MODULE INFORMATION.


C51 COMPILATION COMPLETE.  0 WARNING(S),  0 ERROR(S)

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