I am working on a RGB Led matrix and fast toggling of IO pins matters to me.
I created a simple example project to blink the LED on SAM D10 mini Xplained board. This project uses internal 8Mhz. Then I modified the project just to toggle a pin (PA_10) in the while loop. I measured the frequency of the toggling pin and this is what I get:
I am expecting the frequency to be more or less 4Mhz (8Mhz/2 - since it's toggling). I tested the project with 48Mhz DFLL also and this is what I get on test pin:
I want the toggling as fast as possible. Now the question is, if this is a normal behavior? Or if this has anything to do with internal comm bus (AHB)? Is it possible to change bus clock? How?
I have attached the project too, which I created in Atmel studio 6.2. Please review the project and tell me if I am doing it wrong.