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Asserting CS line in SPI continuous mode

Posted: Thu Dec 09, 2021 9:43 pm
by Tanguy
Hello,

We need to continuously sample some inputs through an external ADC.

First question :
We're using an ESP32 with DMA in continuous mode. It is working fine but CS is kept low as long as the SPI operation isn't interrupted. The problem is most ADC needs the CS line to be pulled high between each transaction. Is there a way to make the CS line high at regular interval? At the end of each outlink list for example?

Second question :
We''ll maybe try to go with the new esp32-C3. Will it be able to provide the same SPI-DMA continuous mode? There is no mention of a register for DMA continuous mode but maybe with the C3 it's enough to have circular linked lists? Technical reference doesn't have the SPI section yet. Any idea when it will be provided?

Thanks,