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#include "project.h"
static volatile uint32_t ticks;
static uint32_t scale = 7;
unsigned led1 = 1000, led2 = 1000;
void
delay_us (uint32_t d)
{
d *= scale;
while (d--)
__asm__ ("nop");
}
void
sys_tick_handler (void)
{
ticks++;
cdcacm_tick();
if (led1)
led1--;
if (led2)
led2--;
if (led1)
gpio_clear (LED1_BANK, LED1_GPIO);
else
gpio_set (LED1_BANK, LED1_GPIO);
if (led2)
gpio_clear (LED2_BANK, LED2_GPIO);
else
gpio_set (LED2_BANK, LED2_GPIO);
}
void
ticker_init (void)
{
uint32_t v, w;
/*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();
/*Calibrate the delay loop */
do {
scale--;
v = ticks;
while (v == ticks)
;
delay_us (1000);
w = ticks;
v++;
w -= v;
} while (w);
}
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