📄 os_sem.lst
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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
241 *********************************************************************************************************
C51 COMPILER V7.20 OS_SEM 06/14/2006 20:19:47 PAGE 5
242 */
243 #if OS_SEM_PEND_EN>0
244 void OSSemPend (OS_EVENT *pevent, INT16U timeout, INT8U *err) 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
if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
*err = OS_ERR_PEVENT_NULL;
return;
}
if (pevent->OSEventType != OS_EVENT_TYPE_SEM) { /* Validate event block type */
*err = OS_ERR_EVENT_TYPE;
return;
}
#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 #endif
290 /*$PAGE*/
291 /*
292 *********************************************************************************************************
293 * POST TO A SEMAPHORE
294 *
295 * Description: This function signals a semaphore
296 *
297 * Arguments : pevent is a pointer to the event control block associated with the desired
298 * semaphore.
299 *
300 * Returns : OS_NO_ERR The call was successful and the semaphore was signaled.
301 * OS_SEM_OVF If the semaphore count exceeded its limit. In other words, you have
302 * signalled the semaphore more often than you waited on it with either
303 * OSSemAccept() or OSSemPend().
C51 COMPILER V7.20 OS_SEM 06/14/2006 20:19:47 PAGE 6
304 * OS_ERR_EVENT_TYPE If you didn't pass a pointer to a semaphore
305 * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer.
306 *********************************************************************************************************
307 */
308 #if OS_SEM_PEND_EN>0
309
310 INT8U OSSemPost (OS_EVENT *pevent) reentrant
311 {
312 1 #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr;
#endif
315 1
316 1
317 1 #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
325 1 OS_ENTER_CRITICAL();
326 1 if (pevent->OSEventGrp != 0x00) { /* See if any task waiting for semaphore */
327 2 OS_EventTaskRdy(pevent, (void *)0, OS_STAT_SEM); /* Ready highest prio task waiting on event */
328 2 OS_EXIT_CRITICAL();
329 2 OS_Sched(); /* Find highest priority task ready to run */
330 2 return (OS_NO_ERR);
331 2 }
332 1 if (pevent->OSEventCnt < 65535) { /* Make sure semaphore will not overflow */
333 2 pevent->OSEventCnt++; /* Increment semaphore count to register event */
334 2 OS_EXIT_CRITICAL();
335 2 return (OS_NO_ERR);
336 2 }
337 1 OS_EXIT_CRITICAL(); /* Semaphore value has reached its maximum */
338 1 return (OS_SEM_OVF);
339 1 }
340 #endif
341 /*$PAGE*/
342 /*
343 *********************************************************************************************************
344 * QUERY A SEMAPHORE
345 *
346 * Description: This function obtains information about a semaphore
347 *
348 * Arguments : pevent is a pointer to the event control block associated with the desired
349 * semaphore
350 *
351 * pdata is a pointer to a structure that will contain information about the
352 * semaphore.
353 *
354 * Returns : OS_NO_ERR The call was successful and the message was sent
355 * OS_ERR_EVENT_TYPE If you are attempting to obtain data from a non semaphore.
356 * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer.
357 *********************************************************************************************************
358 */
359
360 #if OS_SEM_QUERY_EN > 0
INT8U OSSemQuery (OS_EVENT *pevent, OS_SEM_DATA *ppdata) reentrant
{
#if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr;
#endif
C51 COMPILER V7.20 OS_SEM 06/14/2006 20:19:47 PAGE 7
INT8U *psrc;
INT8U *pdest;
#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();
ppdata->OSEventGrp = pevent->OSEventGrp; /* Copy message mailbox wait list */
psrc = &pevent->OSEventTbl[0];
pdest = &ppdata->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
ppdata->OSCnt = pevent->OSEventCnt; /* Get semaphore count */
OS_EXIT_CRITICAL();
return (OS_NO_ERR);
}
#endif /* OS_SEM_QUERY_EN */
418 #endif /* OS_SEM_EN */
MODULE INFORMATION: STATIC OVERLAYABLE
CODE SIZE = 712 ----
CONSTANT SIZE = ---- ----
XDATA SIZE = ---- ----
PDATA SIZE = ---- ----
DATA SIZE = ---- ----
IDATA SIZE = ---- ----
C51 COMPILER V7.20 OS_SEM 06/14/2006 20:19:47 PAGE 8
BIT SIZE = ---- ----
END OF MODULE INFORMATION.
C51 COMPILATION COMPLETE. 0 WARNING(S), 0 ERROR(S)
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