mk20dx128.c for (n=0; n<10; n++) ;

I don't understand this:

Is this not optimized away ?

mk20dx128.c

Perhaps asm volatile ("nop") is better(?)

Frank

Frank B said:

Is this not optimized away ?

Click to expand...

The variable "n" is declared volatile, so the compiler is forced to implement it.

https://github.com/PaulStoffregen/cores/blob/master/teensy3/mk20dx128.c#L371


The 2 MHz initialization consumes more power than using Duff's library. So far, nobody has figured out why, or how to fix it. I'm not currently working on this, but if anyone has any solid ideas, I've love to hear!

PaulStoffregen said:

The variable "n" is declared volatile, so the compiler is forced to implement it.

Click to expand...

Ah...i see! Thank you!!

I see that when my library goes into BLPI it leaves the Clock Out Pin using OSCERCLK0 and instead of using LPO clock. Haven't tried that yet but since I dropped going into VPLR mode in my new library I'll try to figure it out to get that elusive 1mA. The USB stuff is not even intialized when compiling at 2MHZ right? I'm wondering if its the order in starting the clocks? Maybe selecting the fast IRCS before setting the MCG OUT clk to internal ref, thats how I did it. I'll play around with this maybe I'll stumble on to something.