It is very odd.
OSInit();
OSTimeDly(10);
OSTaskCreate(start_task,(void *)0,(OS_STK *)&START_TASK_STK[TASK_STK_SIZE-1],START_TASK_PRIO);
OSStart();
In OSTimeDly(10),there is OS_Enter_CRITICAL() and OS_Exit_Critical(),and when the code is running into OS_Exit_Critical(),HardFault will happen.
void OSTimeDly (INT32U ticks)
{
INT8U y;
#if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr = 0u;
#endif
if (OSIntNesting > 0u) { /* See if trying to call from an ISR */
return;
}
if (OSLockNesting > 0u) { /* See if called with scheduler locked */
return;
}
if (ticks > 0u) { /* 0 means no delay! */
OS_ENTER_CRITICAL();
y = OSTCBCur->OSTCBY; /* Delay current task */
OSRdyTbl[y] &= (OS_PRIO)~OSTCBCur->OSTCBBitX;
if (OSRdyTbl[y] == 0u) {
OSRdyGrp &= (OS_PRIO)~OSTCBCur->OSTCBBitY;
}
OSTCBCur->OSTCBDly = ticks; /* Load ticks in TCB */
OS_EXIT_CRITICAL();
OS_Sched(); /* Find next task to run! */
}
}
But,if I change the code to this:
#if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr = 0u;
#endif
INT8U y;
...
OSInit();
OS_ENTER_CRITICAL();
y = OSTCBCur->OSTCBY; /* Delay current task */
OSRdyTbl[y] &= (OS_PRIO)~OSTCBCur->OSTCBBitX;
if (OSRdyTbl[y] == 0u) {
OSRdyGrp &= (OS_PRIO)~OSTCBCur->OSTCBBitY;
}
OS_EXIT_CRITICAL();
//OSTimeDly(10);
OSTaskCreate(start_task,(void *)0,(OS_STK *)&START_TASK_STK[TASK_STK_SIZE-1],START_TASK_PRIO);
OSStart();
There are also OS_ENTER_CRITICAL() and OS_EXIT_CRITICAL(), But when the code is running into OS_EXIT_CRITICAL(), no HardFault happens.Why? I don't think there is any different.
You are calling OSTimeDly()
before you have started the operating system.
If you want to delay/pause/wait prior to starting the OS (via OSStart()
), you will have to use a "dummy loop" with a volatile, or use a hardware timer (better), etc.