/**************************************************************************//**
* @brief Check if voltage is higher than indicated
*
* @param vdd
* The voltage level to compare against.
* @return
* Returns true if voltage is lower, false otherwise
*****************************************************************************/
bool VDDCHECK_LowVoltage(float vdd)
{
VCMP_Init_TypeDef vcmp = VCMP_INIT_DEFAULT;
/* Configure VCMP */
vcmp.triggerLevel = VCMP_VoltageToLevel(vdd);
vcmp.warmup = vcmpWarmTime128Cycles;
vcmp.lowPowerRef = false;
vcmp.enable = true;
VCMP_Init(&vcmp);
/* Delay until warm up ready */
while (!VCMP_Ready()) ;
/* If zero result, voltage is lower */
if (VCMP_VDDHigher()) return false;
/* Otherwise return false */
return true;
}
/***************************************************************************//**
* @brief
* Configure and enable Voltage Comparator
*
* @param[in] vcmpInit
* VCMP Initialization structure
******************************************************************************/
void VCMP_Init(const VCMP_Init_TypeDef *vcmpInit)
{
/* Verify input */
EFM_ASSERT((vcmpInit->inactive == 0) || (vcmpInit->inactive == 1));
EFM_ASSERT((vcmpInit->biasProg >= 0) && (vcmpInit->biasProg < 16));
/* Configure Half Bias setting */
if (vcmpInit->halfBias)
{
VCMP->CTRL |= VCMP_CTRL_HALFBIAS;
}
else
{
VCMP->CTRL &= ~(VCMP_CTRL_HALFBIAS);
}
/* Configure bias prog */
VCMP->CTRL &= ~(_VCMP_CTRL_BIASPROG_MASK);
VCMP->CTRL |= (vcmpInit->biasProg << _VCMP_CTRL_BIASPROG_SHIFT);
/* Configure sense for falling edge */
if (vcmpInit->irqFalling)
{
VCMP->CTRL |= VCMP_CTRL_IFALL;
}
else
{
VCMP->CTRL &= ~(VCMP_CTRL_IFALL);
}
/* Configure sense for rising edge */
if (vcmpInit->irqRising)
{
VCMP->CTRL |= VCMP_CTRL_IRISE;
}
else
{
VCMP->CTRL &= ~(VCMP_CTRL_IRISE);
}
/* Configure warm-up time */
VCMP->CTRL &= ~(_VCMP_CTRL_WARMTIME_MASK);
VCMP->CTRL |= (vcmpInit->warmup << _VCMP_CTRL_WARMTIME_SHIFT);
/* Configure hysteresis */
switch (vcmpInit->hyst)
{
case vcmpHyst20mV:
VCMP->CTRL |= VCMP_CTRL_HYSTEN;
break;
case vcmpHystNone:
VCMP->CTRL &= ~(VCMP_CTRL_HYSTEN);
break;
default:
break;
}
/* Configure inactive output value */
VCMP->CTRL |= (vcmpInit->inactive << _VCMP_CTRL_INACTVAL_SHIFT);
/* Configure trigger level */
VCMP_TriggerSet(vcmpInit->triggerLevel);
/* Enable or disable VCMP */
if (vcmpInit->enable)
{
VCMP->CTRL |= VCMP_CTRL_EN;
}
else
{
VCMP->CTRL &= ~(VCMP_CTRL_EN);
}
/* If Low Power Reference is enabled, wait until VCMP is ready */
/* before enabling it, see reference manual for deatils */
/* Configuring Low Power Ref without enable has no effect */
if(vcmpInit->lowPowerRef && vcmpInit->enable)
{
/* Poll for VCMP ready */
while(!VCMP_Ready());
VCMP_LowPowerRefSet(vcmpInit->lowPowerRef);
}
/* Clear edge interrupt */
VCMP_IntClear(VCMP_IF_EDGE);
}
