Arbitrary waveform generation using timer DMA-burst feature: what is the callback when DMA transfer is complete/half complete?

[nikwest]

I am expecting there must be a similar callback function like HAL_UART_TxCpltCallback, HAL_UART_TxHalfCpltCallback in case of using UARTs when using DMA-burst for generating arbitrary waveforms with PWM in order to be able to update the memory buffer used for DMA?

I only can find callbacks which get called with every PWM pulse.

[KnarfB]

You can register your own callback functions by using HAL_DMA_RegisterCallback like

HAL_DMA_RegisterCallback( htim3.hdma[TIM_DMA_ID_CC3], HAL_DMA_XFER_HALFCPLT_CB_ID, XferHalfCpltCallback );

where  void XferHalfCpltCallback(DMA_HandleTypeDef * _hdma) is the callback function which you implement.

[nikwest]

Thank you. I have briefly tried this already, but I'll try again. I was asuming the TIM_PWM code is consuming the DMA callbacks.

[nikwest]

No, unfortunately your suggestions does not work for me. The callback doesn't get called. Not sure what I am doing wrong here.

[KnarfB]

You're right. Started your code and set a breakpoint on the native IRQ Handler DMA1_Channel7_IRQHandler which is hit. Stepping further I ended up at the __weak default HAL_TIM_PWM_PulseFinishedHalfCpltCallback. Defining your own HAL_TIM_PWM_PulseFinishedHalfCpltCallback should work.

[nikwest]

yep, that what was my conclusion, too. But it's called with every pulse and not when DMA transfer is complete or half complete. Or maybe I misinterpreted that.

[NRoth.3]

void HAL_TIM_PeriodElapsedHalfCpltCallback(TIM_HandleTypeDef *htim)

works great and is called at the end of the DMA Transfers.