app/ticker.c


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#include "project.h"

static volatile uint32_t delay_ms_count;
uint32_t ticks;

void
delay_us (uint32_t d)
{
  d *= 36;
  while (d--)
    {
      __asm__ ("nop");
    }
}

void
sys_tick_handler (void)
{
  if (delay_ms_count)
    delay_ms_count--;

  ticks++;

  led_tick ();
  lcd_refresh_wdt ();
}


void
delay_ms (uint32_t d)
{
  delay_ms_count = d;
  while (delay_ms_count);
}


void
ticker_init (void)
{

  /*Start periodic timer */
  systick_set_clocksource (STK_CSR_CLKSOURCE_AHB_DIV8);
  /* 48MHz / 8 = > 6Mhz */
  systick_set_reload (6000);
  /* 6MHz / 6000 => 1kHz */
  systick_interrupt_enable ();
  systick_counter_enable ();


}