/** Set interrupt for specified timestamp
*
* @param timestamp The time in ticks to be set
*/
void lp_ticker_set_interrupt(timestamp_t timestamp)
{
if (timestamp == 0) {
timestamp = 1;
}
GPT_StopTimer(GPT2);
GPT_SetOutputCompareValue(GPT2, kGPT_OutputCompare_Channel1, timestamp);
GPT_ClearStatusFlags(GPT2, kGPT_OutputCompare1Flag);
GPT_EnableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
GPT_StartTimer(GPT2);
}
static rt_err_t rt1052_hwtimer_start(rt_hwtimer_t *timer, rt_uint32_t cnt, rt_hwtimer_mode_t mode)
{
GPT_Type *hwtimer_dev;
hwtimer_dev = (GPT_Type *)timer->parent.user_data;
RT_ASSERT(timer != RT_NULL);
hwtimer_dev->CR |= (mode == HWTIMER_MODE_PERIOD) ? GPT_CR_FRR_MASK : 0U;
GPT_SetOutputCompareValue(hwtimer_dev, kGPT_OutputCompare_Channel1, cnt);
GPT_EnableInterrupts(hwtimer_dev, kGPT_OutputCompare1InterruptEnable);
NVIC_Configuration();
GPT_StartTimer(hwtimer_dev);
return RT_EOK;
}
/** Initialize the low power ticker
*
*/
void lp_ticker_init(void)
{
gpt_config_t gptConfig;
if (!lp_ticker_inited) {
/* Setup GPT */
GPT_GetDefaultConfig(&gptConfig);
/* Use 32kHz drive */
gptConfig.clockSource = kGPT_ClockSource_LowFreq;
gptConfig.enableFreeRun = true;
gptConfig.enableMode = false;
GPT_Init(GPT2, &gptConfig);
GPT_EnableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
NVIC_ClearPendingIRQ(GPT2_IRQn);
NVIC_SetVector(GPT2_IRQn, (uint32_t)gpt_isr);
EnableIRQ(GPT2_IRQn);
GPT_StartTimer(GPT2);
lp_ticker_inited = true;
} else {
GPT_DisableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
}
}