I have a FRDM-KL05Z board and I noticed something peculiar that's bothering me.
The fastest crystal on the board 8.0 MHz.
Yet one of the LED blink projects (in Keil uVision, I think) uses a delay loop that simply increments a local variable. I doesn't use any system timer or interrupt.
The trouble is that given the numbers it is counting to, there is no way it should be able to do this in the time it actually takes. It seems like it is actually running at its max speed of 48Mhz.
Is there a clock multiplier on chip or some other internal reference?