Resetting Timer Unit used for Timer Interrupt

[justusandjustic]

I'm trying to use a timer to catch the end of a ModBus message.  ModBus has a minimum delay time between messages, so my goal was to have the interrupt period be the minimum delay time, and have the timer reset whenever a new character is received.  However, when I create a TimerInt component based off the TimerUnit component, the ResetCounter function because 'grayed-out'.  I know this is a common method for determining the end of a ModBus message, so how would I go about doing this with Processor Expert?

[Alexis_A]

Dear justusandjustice‌,

Could you let me know which MCU are you using?

Best Regards,

Alexis Andalon

[justusandjustic]

Thanks for the response.  The chip is S9KEAZN64MLC2.  The project is in Kinetis Design Studio with Processor Expert.

-Josiah

[Alexis_A]

Dear Josiah,

In the description of this function there's the next note:

But I think if you use the SetPeriodTicks could be a good replace to this function.

Best Regards.

Alexis Andalon

[justusandjustic]

Alexis,

Yes, I had seen that note, but I didn't think that was applicable, because when I create the TimerUnit component, I am able to enabled the ResetCounter function, but when I attach a TimerInt component to that TimerUnit, I am no longer able to use that function.  Why would creating the Interrupt component disable that function?

As for using the SetPeriodTicks function, are you suggesting that I simply continually move the goal time forward instead of resetting the counter?  That might work.  I'll give that a try.

-Josiah

[Alexis_A]

Hi Josiah,

When you enable the interrupt the counter will be cleared when the interrupt is triggered, that's why this function disable the reset counter.

Best Regards,

Alexis Andalon

[justusandjustic]

I think I understand.  So the interrupt is triggered by the reset, so resetting it would also trigger the interrupt.  I want the interrupt to be triggered by the match, and then the counter to be reset, but that's not how it works, apparently.

Thanks for your help,

-Josiah