S32KのトピックRe: S32K3 DMA with SPI

S32K3 DMA with SPI

sobo — Tue, 23 Aug 2022 14:35:37 GMT

Hello,

For our project we would like to use DMA with SPI, I read the example :

C:\NXP\SW32K3_RTD_4.4_2.0.1\eclipse\plugins\Spi_TS_T40D34M20I1R0\examples\EBT\Spi_Transfer_S32K344

In the description the slave is used with DMA.

In configuration I see the configuration (MCL) the DMA logic channel for RX and TX.

But I don't understand how the DMA works here as we used Spi_WriteIB and Spi_ReadIB to copy and read buffer for slave.

When DMA is "triggered" and from which buffer to/from which it transfer data ?

In main.c functions

/* Copy transmitted data to internal buffer */
Spi_WriteIB(1u, TxChBuf1);

/* This sequence of slave: transferring 10 frame 16 bits using Dma */
Spi_AsyncTransmit(SpiConf_SpiSequence_SpiSequence_Slave);

/* Read received buffer with data length configured in configuration tool */
Spi_ReadIB(1u, RxChBuf1);

Sophie

Re: S32K3 DMA with SPI

cuongnguyenphu — Tue, 30 Aug 2022 07:00:26 GMT

Hi @sobo , sorry for late response
In this example, Channel 1 as Slave using FlexIO with DMA method:

Spi_WriteIB(1u, TxChBuf1) will be used to copy transmit data from TxChBuf1 to Internal buffer:

Then, when Spi_AsyncTransmit(SpiConf_SpiSequence_SpiSequence_Slave) is called, it will called until Flexio_Spi_Ip_AsyncTransmit(), and in this function, 2 Ip will be called to setup Dma parameter and value, then set command :

For Receive data, when using Spi_ReadIB(1u, RxChBuf1), data will be store in Rx buffer by Dma then copy to RxChBuf1:

Re: S32K3 DMA with SPI

sobo — Wed, 31 Aug 2022 07:34:03 GMT

Thank you for answer, it help me to better understand this part.

Re: S32K3 DMA with SPI

MVR — Thu, 13 Feb 2025 19:37:38 GMT

Hello @cuongnguyenphu,

How can I use these functions with SPI defined as master mode?

Thanks,

MVR

Re: S32K3 DMA with SPI

LeaP — Wed, 26 Mar 2025 13:43:24 GMT

Hi, @cuongnguyenphu,

I am also looking at how to configure both the Master and the Slave with DMA.
I cannot find anything on this online and in the user manuals.

The only thing that works for me is when the Slave is configured to do Async Transmit with DMA, and the Master is configured Sync Transmit without DMA

But I would like both to use DMA

Is it possible?

Thank you for your help,
BR
Léa