#include "rcc.h"
#include "timer.h"

void tim4_init(void) {
  // Enable timer
  RCC->APB1ENR |= RCC_APB1ENR_TIM4_ENABLE;

  // Reset timer
  TIM4->CR1 = 0x0000;
  TIM4->CR2 = 0x0000;

  // Set prescaler
  // f_clk = 48MHz -> /48000 = 1KHz counting frequency = 1ms
  TIM4->PSC = (uint16_t) 48000 - 1;

  // Set ARR to maximum value to get 1ms between updates
  TIM4->ARR = (uint16_t) 0xFFFF;
}

void tim4_start(void) {
  TIM4->CR1 |= TIM_ENABLE;
}