Once the DAC DMA is started, do I need to stop it in order to change the content of the buffer? Or I can simply do a HAL_DAC_Start_DMA() again with an updated buffer?

[VNado.1]

..

[waclawek.jan]

> Once the DAC DMA is started, do I need to stop it in order to change the content of the buffer?

DMA does not care what you do in your buffer. If it runs (e.g. in Circular mode), DMA simply takes whatever it finds there and puts it into DAC.

JW

[Ozone]

You cannot stop DMA in a reproducible manner, the data item will be random.

You would need to divide the output into small enough sections.