Oh, the technical reference manual notes that the DMA channel is shared. So I guess it's a hardware limitation? GP-SPI3 is also a general purpose SPI controller, but shares a DMA channel with ADC and DAC modules. GP-SPI3 works as either a master or a slave. As a master, GP-SPI3 provides three CS lin...

I just ran into this issue, and it looks like the IDF is hardcoding SPI3_HOST for both the DAC and ADC: https://github.com/espressif/esp-idf/blob/a322e6bdad4b6675d4597fb2722eea2851ba88cb/components/driver/dac/esp32s2/dac_dma.c#L37 https://github.com/espressif/esp-idf/blob/a322e6bdad4b6675d4597fb2722...