#include "delay.h" #include uint32_t us_ticks; void systick_configure() { SysTick->LOAD = SYSTICK_LOAD; SysTick->VAL = 0; SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | SysTick_CTRL_ENABLE_Msk; //| SysTick_CTRL_TICKINT_Msk; us_ticks = 0; } void systick_handler() { us_ticks++; }