MKMxxZxxACxx5 Bare Metal Software Drivers  R4.1.6
Reference Manual
FLL IRC Clock Sources

Overview

List of internal reference clock sources.

Macros

#define SLOWCLK_SRC
 slow clock (32 KHz IRC)
 
#define FASTCLK_SRC
 fast clock (4MHz IRC); use FLL_SetFastClkDiv macro to scale down 4MHz IRC frequency.