WICED Studio Wi-Fi Combo

[HaSo_2959646]

Hello everyone,

I'm trying to transfer data over SPI protocol using DMA. I see examples of SPI_SLAVE and SPI_MASTER but they don't use DMA. I was wondering if someone has done this before?

Kind regards,

Hamid.

[RaktimR_11]

Which platform are you using?

[HaSo_2959646]

CYW943907EVAL1F

[RaktimR_11 · Accepted solution]

Unfortunately, the DMA for 43907 is not really exposed so that applications on top can use that. That's why you can't see it in SPI_SLAVE or SPI_MASTER implementation amongst which 43907 only supports master mode. Please check this blog post SPI in CYW43907 if you are facing any difficulties in SPI implementation.

[HaSo_2959646]

I tested SPI using that example. When you increase the tx buffer size > 4, in inter-byte time delay increases and byte order gets messed up…this issue was also reported here:

https://community.cypress.com/message/142610#142610

I want to transmit larger packets of data without inter-byte delay, so how do I overcome this issue?

I can try include DMA in the SPI_MODE, but this doesn’t seem to fix the problem:

#define SPI_MODE     ( SPI_CLOCK_RISING_EDGE | SPI_CLOCK_IDLE_LOW | SPI_MSB_FIRST | SPI_USE_DMA )

How do I correctly use the DMA?

[RaktimR_11]

Unfortunately, you can't really use SPI over DMA; it's not exposed on the surface in WICED. You have to use the GSIO driver present in WICED. 

[PriyaM_16]

Please share the changes that you have made to send larger packets of data.

I tried to increase the tx buffer size to 5 and it appears to receive the data in orrect sequence.

[David_Zhang]

hi   PriyaM:

     please check the code,  can you share the SPI over DMA demo code?? tks;

    Re: SPI rate change in code