topic Re: Trouble with delay in Classic/Legacy CodeWarrior

Trouble with delay

ignisuti — Fri, 03 Jun 2011 04:18:19 GMT

I'm using the True-Time Simulator & Real Time Debugger Ver. 6.1 Build 9279.

For some reason, my code keeps breaking in this function on the while loop.

void delay_ms(unsigned short time){   //max delay time should be 65.535 seconds    unsigned long count;        //enable_timer2_interrupt();    t2Count = 0;        set_timer_delay(&count);    while(!timer_expired_delay(count, time)){;}    //if(startTCPIPflash==FALSE)    //    DISABLE_INT_TIMER2;    }

Please help me figure out what to look for to fix this problem.

It's odd because it works immediatly after initialization, but then a short while later, my 1ms timer interrupts and trys to write data to an LCD. That function calls this delay_ms() function and fails.

Re: Trouble with delay

ignisuti — Fri, 03 Jun 2011 22:11:04 GMT

Okay, I figured out that when putting "EnableInterrupts" right before my call to delay_ms(), it works.

So, this means something is disabling my interrupts after I've enabled them in my initialization routine. I can't find where though. Any ideas on what to look for?

Re: Trouble with delay

ignisuti — Sat, 04 Jun 2011 01:27:12 GMT

Okay, I think I'm getting closer. I believe my timer_1_interrupt function is disabling interrupts. Is this normal? Or did the compiler tell it to do this because I'm calling a function in the interrupt that is also called outside the interrupt?

My whole problem occurs when MAIN_service_routine() trys to call delay_ms() which relies on this interrupt (see below). Simply adding "EnableInterrupts;" before my call to MAIN_service_routine() fixes the problem. However, I'd like to understand why this is needed.

/* =================================================================================================  FUNCTION DESCRIPTION:==      Interrupt - Hardware Timer 1 - Configured to trigger every 1ms.==          Triggers all Service Routines.====  OUTPUTS:==      N/A== =============================================================================================*/__interrupt void timer_1_interrupt(void)    {    /* Local Variables. */    static BLN service_routine_active = FALSE;    DEBUG_checkpoint( CP_ENTER_timer_1_interrupt ); //Mark Checkpoint.    RESET_TIMER1;                           //Reset timer (allow this interrupt to occur again).        t1Count++;                              //Update ms counter used for software timers.        /* Check if Service Routine already processing (prevent undesired recursion). */    if( service_routine_active == FALSE )        {                service_routine_active = TRUE;      //Mark service routine active.                      MAIN_service_routine();             //Call Main Service Routine.                service_routine_active = FALSE;     //Mark service routine inactive.        }                                           DEBUG_checkpoint( CP_EXIT_timer_1_interrupt ); //Mark Checkpoint.            } /* timer_1_interrupt() */