Update MPER register with every HRTIM period

[Odiug]

I am also failing in reproducing the DMA example from https://wiki.st.com/stm32mcu/wiki/Getting_started_with_HRTIM#To_go_further_about_DMA_burst.

HAL_HRTIM_BurstDMAConfig() is mentioned in the text, but not present in the code example. Did you miss to put it into the example?

Minor issue: I find it weird to edit HAL_HRTIM_MspInit() to change DMA_MEMORY_TO_PERIPH to DMA_MEMORY_TO_MEMORY as this gets overwritten by the next code generation.

Would it be safe to put this in the user section below:

    /* USER CODE BEGIN HRTIM1_MspInit 1 */
    hdma_hrtim1_a.Init.Direction = DMA_MEMORY_TO_MEMORY;

    if (HAL_DMA_Init(&hdma_hrtim1_a) != HAL_OK)
    {
      Error_Handler();
    }
    /* USER CODE END HRTIM1_MspInit 1 */

This would result calling HAL_DMA_Init() twice. Is this OK?

Kind regards,

Guido

[Odiug]

Sorry, I was wrong. HAL_HRTIM_BurstDMAConfig() is called in the autogenerated MX_HRTIM1_Init().

[Odiug]

What I would like to achieve in the end is a running HRTIM1 where the MPER register gets updated with every period. I assumed this can be achieved with burst DMA.

The example from https://wiki.st.com/stm32mcu/wiki/Getting_started_with_HRTIM#To_go_further_about_DMA_burst is the only one, I could find.

In order to learn more about burst DMA, I started experimenting. First, I wanted to update multiple registers.

I am writing to the four CMP registers and preset them with different values to visualize it better:

static uint32_t reg_update[] = {
		0xaaaa,
		0xbbbb,
		0xcccc,
		0xdddd,
};

static inline void BurstDMA_Test(void)
{
	HAL_StatusTypeDef ret;

	HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP1xR = 0x11;
	HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP2xR = 0x22;
	HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP3xR = 0x33;
	HRTIM1->sTimerxRegs[HRTIM_TIMERINDEX_TIMER_A].CMP4xR = 0x44;

	ret = HAL_HRTIM_BurstDMATransfer(
			&hhrtim1, HRTIM_TIMERINDEX_TIMER_A, (uint32_t)reg_update, 4);
	if (ret != HAL_OK)
	{
	   Error_Handler();
	}
}

 But that just gave me:

So, the first value is copied into all the configure registers.

OK, so maybe I have to set the "Increment Address" for the DMA configuration:

But this results in only one register being updated:

I am puzzled!

So, my first piece in understanding would be: How to update multiple registers from a single buffer.

Kind regards,

Guido

[Christian N]

This post has been escalated to the ST Online Support Team for additional assistance. We'll contact you directly.

Regards,
Christian