#include "project.h"

static volatile uint32_t delay_ms_count;
volatile uint32_t ticks;
static volatile int tick_ready;

uint32_t clock_scale = 72;

void
delay_us (uint32_t d)
{
  d *= clock_scale;

  while (d--)
    __asm__ ("nop");
}



void
sys_tick_handler (void)
{
  static unsigned slow = 0;
  static unsigned medium = 0;

  if (delay_ms_count)
    delay_ms_count--;

  ticks++;

  if (!tick_ready)
    return;

  //buttons_ticker();
  //
  led_tick();
  usart_ticker();


  medium++;

  if (medium < 1000) return;

  medium = 0;

  //target_tick();

  slow++;

  if (slow < 5) return;

  slow = 0;

  logic_tick();


}



void
delay_ms (uint32_t d)
{
  delay_ms_count = d;

  while (delay_ms_count);
}


void
ticker_init (void)
{
  uint32_t v, w;

  /*Start periodic timer */
  systick_set_clocksource (STK_CSR_CLKSOURCE_AHB_DIV8);
  /* 72MHz / 8 = > 9Mhz */
  systick_set_reload (9000);
  /* 9MHz / 9000 => 1kHz */
  systick_interrupt_enable();
  systick_counter_enable();

  do {
    clock_scale--;
    v = ticks;

    while (v == ticks);

    delay_us (1000);
    w = ticks;
    v++;
    w -= v;
  } while (w);


  tick_ready = 1;

  SCS_DEMCR |= SCS_DEMCR_TRCENA;
  SCS_DWT_CTRL |= SCS_DWT_CTRL_CYCCNTENA;
}