declaration inside SR_Service_Prepare()

MIOS programming (C)
1

just a little question.

what is the most efficient option?

1/ variables globally declared and used in SR_Service_Prepare()

2/ variables locally declared inside SR_Service_Prepare() and used in SR_Service_Prepare()

I guess in the case 2/ each time the SR_Service_Prepare() is called, declarations eat cpu time … right ?

so it may be the 1/ to choose

?!

2

  1. is the most efficient solution as it only allocates local stack (in zero time) - but take care that stack memory is limited (1024 bytes), don’t declare huge arrays there

  2. is expensive since it allocates RAM statically, and it’s bad programming style - you want to avoid the usage of global variables whenever possible.

Best Regards, Thorsten.

3

I was almost sure I had to ask this :slight_smile:

thanks a lot.

I understand the logic under the hood