SPI communication via DMA in background using ppi and a timer

RE: SPI communication via DMA in background using ppi and a timer

Vidar Berg — Wed, 12 Jun 2019 13:57:20 GMT

We don't have an example for this, but the driver documentation which I linked to earlier explains how you can enable list mode (NRF_DRV_SPI_FLAG_TX_POSTINC) and start transfers through PPI.

RE: SPI communication via DMA in background using ppi and a timer

Constantin — Thu, 06 Jun 2019 13:30:43 GMT

Sorry no. The SPI Master Example is the lowest performance ever. I would like to have an Example with ArrayList mode which runs without CPU usage like the Example of Martin.

I did not mean to use TWIM and SPIM at the same time but SPIM in Arraylist mode and normal SPIM. It is not working when the SPIM is in Arraylist mode I cannot write to it although no communication is going. I have to uninit it and init again without Arraylist.

RE: SPI communication via DMA in background using ppi and a timer

Vidar Berg — Thu, 06 Jun 2019 12:59:57 GMT

Hi,

Have you tried to have a look at the SDK example: SPI Master Example. The driver documentation can be found here: SPIM.

[quote userid="18764" url="~/f/nordic-q-a/48198/spi-communication-via-dma-in-background-using-ppi-and-a-timer"]So far in the TWIM example it is not possible to switch between DMA and direct write without uninitialization of the SPI.[/quote]

The TWIM0 and SPIM0 are shared so they cannot be used at the same time. Maybe you can use another TWIM or SPIM instance instead?

RE: SPI communication via DMA in background using ppi and a timer

CheMax — Wed, 05 Jun 2019 13:02:56 GMT

Hi,

I think. you can try find some code examples in this topic : ads1299-reading-register_spi_nrf52832 or /nordic-q-a/37497/rare-counter-error

Best regards,

Max