// #include "sam3xa/include/component/component_rtt.h"
// #include "sam3xa/include/sam3x8e.h"
#include "obd2_timer.h"

void obd2_timer_init(void)
{
    /* enable the timer: reset the RTT, enable the alarm interrupt, set the prescaler value equal to the processor clock speed*/
    RTT->RTT_MR = RTT_MR_RTTRST | RTT_MR_ALMIEN | RTT_MR_RTPRES(32768/2);
    /* set the alarm value to 0*/
    RTT->RTT_AR = 0;
    /* enable the interrupt*/
    NVIC_EnableIRQ(RTT_IRQn);
}

void obd2_timer_reset()
{
    /* To prevent several executions of the interrupt handler,
     the interrupt must be disabled in the interrupt handler
     and re-enabled when the status register is cleared.
  */
  /* disable interrupts */
  RTT->RTT_MR &= ~RTT_MR_ALMIEN;
  /* clear the status register */
  RTT->RTT_SR;
  /* set the alarm value to 0*/
  RTT->RTT_AR = 0;
  /* re-enable the interrupt*/
  RTT->RTT_MR |= RTT_MR_ALMIEN;
  /* reset the RTT*/
  RTT->RTT_MR |= RTT_MR_RTTRST;

}