#ifndef _SYSTEM_SAMR21_H_INCLUDED_ #define _SYSTEM_SAMR21_H_INCLUDED_ #ifdef __cplusplus extern "C" { #endif #include <stdint.h> extern uint32_t SystemCoreClock; /*!< System Clock Frequency (Core Clock) */ void SystemInit(void); void SystemCoreClockUpdate(void); #ifdef __cplusplus } #endif #endif /* SYSTEM_SAMR21_H_INCLUDED */