Function BURTC_Init

bsp/efm32/Libraries/emlib/src/em_burtc.c:101–162

/ * @brief Initialize BURTC * * @details * Configures the BURTC peripheral. * * @note * Before initialization, BURTC module must first be enabled by clearing the * reset bit in the RMU, i.e. * @verbatim * RMU_ResetControl(rmuResetBU, false); * @endverbatim * Compare channel 0 must be configured outside this function, before * initialization if enable is set to true. The co

 *   Pointer to BURTC initialization structure
 ******************************************************************************/
void BURTC_Init(const BURTC_Init_TypeDef *burtcInit)
{
  uint32_t ctrl;
  uint32_t presc;

  /* Check initializer structure integrity */
  EFM_ASSERT(burtcInit != (BURTC_Init_TypeDef *) 0);
  /* Clock divider must be between 1 and 128, really on the form 2^n */
  EFM_ASSERT((burtcInit->clkDiv >= 1) && (burtcInit->clkDiv <= 128));
  /* Ignored compare bits during low power operation must be less than 7 */
  /* Note! Giant Gecko revision C errata, do NOT use LPCOMP=7 */
  EFM_ASSERT(burtcInit->lowPowerComp <= 6);
  /* You cannot enable the BURTC if mode is set to disabled */
  EFM_ASSERT((burtcInit->enable == false) ||
             ((burtcInit->enable == true) && (burtcInit->mode != burtcModeDisable)));
  /* Low power mode is only available with LFRCO or LFXO as clock source */
  EFM_ASSERT((burtcInit->clkSel != burtcClkSelULFRCO) ||
             ((burtcInit->clkSel == burtcClkSelULFRCO) && (burtcInit->lowPowerMode == burtcLPDisable)));

  /* Calculate prescaler value from clock divider input */
  /* Note! If clock select (clkSel) is ULFRCO, a non-zero clkDiv will select */
  /* 1kHz clock source, while any other value will use a 2kHz ULFRCO clock */
  presc = BURTC_DivToLog2(burtcInit->clkDiv);

  /* Make sure all registers are updated simultaneously */
  if (burtcInit->enable)
  {
    BURTC_FreezeEnable(true);
  }

  /* Configure low power mode */
  BURTC->LPMODE = (uint32_t)(burtcInit->lowPowerMode);

  /* New configuration */
  ctrl = ((BURTC_CTRL_RSTEN) |
          (burtcInit->mode) |
          (burtcInit->debugRun << _BURTC_CTRL_DEBUGRUN_SHIFT) |
          (burtcInit->compare0Top << _BURTC_CTRL_COMP0TOP_SHIFT) |
          (burtcInit->lowPowerComp << _BURTC_CTRL_LPCOMP_SHIFT) |
          (presc << _BURTC_CTRL_PRESC_SHIFT) |
          (burtcInit->clkSel) |
          (burtcInit->timeStamp << _BURTC_CTRL_BUMODETSEN_SHIFT));

  /* Clear interrupts */
  BURTC->IFC = 0xFFFFFFFF;

  /* Set new configuration */
  BURTC->CTRL = ctrl;

  /* Enable BURTC and counter */
  if (burtcInit->enable)
  {
    /* To enable BURTC counter, we need to disable reset */
    BURTC_Enable(true);

    /* Clear freeze */
    BURTC_FreezeEnable(false);