TM4C129ENCPDT: Delay using Timer

Kurian,

There could be something on your interrupt implementation, you did not send that part. Did you test that interrupts occur?

Also on your code, you are loading the timer with the system clock. You want to load it with the pause cycles you are are looking for. And if it is a one shot count only, for a pause, then PERIODIC ain't the best option, since you are reconfiguring the timer on the next call of the function. Another detail, it might not be too good to disable and re-enable the timer peripheral "every time the function is called".

However, the code you presented blocks the processor on the while(DelaySet) loop. You won't be able to do anything else until the flag is set - which is not that useful; you shall aim to set some sort of semaphores, and decide on the code executions according to those. During the wait time, you shall either be sleeping or using your processor for other important tasks...

Rgds

Thank you Amit and Bruno.

The interrupt is occurring, I have analyzed it using break points. considering the discussed points the modifications on timer configuration and the interrupt handler are as follows.  But the issue is, these codes are running in execution on detail debug analysis. but the delay function is not returning back to where it has been call. While on testing, found that the continues execution of a 1 ms delayed toggled I/O write with 'ROM_SysCtlDelay()' is working but the delay function cal is not. 

//------------------------------------------------------------------------------------------

ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER3);
while(!SysCtlPeripheralReady(SYSCTL_PERIPH_TIMER3)){}

ROM_TimerConfigure(TIMER3_BASE, TIMER_CFG_ONE_SHOT);

ROM_TimerLoadSet(TIMER3_BASE, TIMER_A, g_ui32SysClock);              // 120Mhz

//--------------------------------------------------------------------------------------------------------------------------------------------

void Delay(uint32_t Delay_value)
{
uint32_t Timer_Count;

Timer_Count = (120000 * Delay_value); // Count calcultion for value in milli sec

ROM_IntEnable(INT_TIMER3A);
ROM_TimerIntEnable(TIMER3_BASE, TIMER_TIMA_TIMEOUT);
ROM_TimerLoadSet(TIMER3_BASE, INT_TIMER3A, Timer_Count);
ROM_TimerEnable(TIMER3_BASE, TIMER_A);

while(DelaySet_Flag <1) {}                    //delayset flag is initially 0 

DelaySet_Flag=0;      
ROM_TimerIntDisable(TIMER3_BASE, TIMER_A); // Disable Timer3 interrupt
ROM_TimerDisable(TIMER3_BASE, TIMER_A); // Disable Timer3
}

--------------------------------------------------------------------------------------------------------------------------------------------------------------

void Timer3IntHandler(void)
{
Interrupt_Flag = (Interrupt_Flag | Timer3_interrupt);
ROM_TimerIntClear(TIMER3_BASE, TIMER_TIMA_TIMEOUT);
DelaySet_Flag++;
}

KurianThomas said:

the delay function is not returning back to where it has been call

Are you saying it is returning to a wrong memory execution location? Or is it stuck in one of your conditional loops?

Maybe you are continuously going back into the timer ISR, because you are only clearing one specific interrupt flag (TIMER_TIMA_TIMEOUT) and there might be some other flag active? See the API examples, normally inside any IRS which requires flag clearing, the sequence is: read all the flags into a variable, clear ALL the interrupts, and take the appropriate measures according to each interrupt cause stored in the variable.