Priming periodic PPI tasks (Force timer event)

[eyalasko]

Hi, 

I'm trying to utilize PPI system to generate repetitive sequence of tasks (lets call them Task A, B, C, D, E, F) at 0,10,20,40,60,80 ms every second.
i.e. I need to have timing on 0,10,20,40,60,80, 1000,1010,1020,1040,1060,1080, 2000, 2010,2020...  ms boundaries

I'm using Timer4 6*compare registers the following way:

• PPI0 - Event from T4CCR0 = 10ms, Task B (some task)
• PPI1 - Event from T4CCR1 = 20ms, Task C (some other task)
• ...
• PPI4 - Event from T4CCR4 = 80ms, Task F
• and PPI5 - Event from T4CCR5 = 1000ms, Task A.
  Also, T4CCR5 uses SHORTS register for T4_CLEAR task

This way I can get the following timing: 10(B)-20(c)-40(D)-60(E)-80(F) - 1000(A)-1010(B)-1020(c)-1040(D)-1060(E)-1080(F) - 2000(B) which is as desired EXCLUDING the very first task at t=0

Is there a way to 'prime' this synchronous machine  by 'forcing' T4CCR5 event upon startup?

Is there a way to set T4 initial value to specific value , i.e. start at 1000ms value that will immediately activate PPI5 and clear itself  ?

Thanks in advance for any advice

[Jørgen Holmefjord]

Hi,

This comment should answer your first question. 

Is there any reason that you cannot trigger the first task manually when you start the timer?

Best regards,
Jørgen