Question
STM32H7B0 DFSDM has eight filters but only four DMA lines?
I’m starting a project with the STM32H7B0 which will heavily utilize the DFSDM (DFSDM1, specifically). I see that there are eight filters in this instantiation, unlike other STM32s I’ve used which only had four. But when I look at the DMAMUX inputs (Reference Manual Table 102), I see only four assigned to DFSDM1: numbers 101-104, labeled DFSDM1_dma0/1/2/3.
How are these four lines mapped to the eight DFSDM1 filters? The obvious interpretation would be that they come from filters 0-3, and filters 4-7 aren’t DMA capable at all. But then why include the extra four filters? Does anyone actually use the DFSDM *without* DMA (there’s no FIFO...)? What am I missing here?