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PSoC™ 5, 3 & 1

Anonymous
Not applicable

Hello! I am new in PsoC and i have following problem:

   

A SPI - Slave receives 4 16-bit values and triggers an FIFO-Full interrupt. This interrupt triggers a DMA , which reads out the data out of the FIFO using following sourceadress: SPIS_RXDATA_PTR.

   

The DMA has 4 Bytes per Burst, length 2000 and request per burst = 1;

   

This works, the first 4 values gets saved correctly in a buffer-array, but the problem is, that the FIFO-Full interrupt stays high and doesn't return to zero! A new transmission is not possible anymore.

   

I have tried reading the data out of the SPI-Slave using SPIS_ReadRxData(). In this case the FIFO-Full interrupt returns to zero.

   

Do i miss anything? How is it possible to let the FIFO-Full interrupt return to zero after reading out 4 values by the dma?

   

 

   

Thanks a lot!

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1 Reply
Anonymous
Not applicable

Hi Reini,

   

 

   

There is a code example on use of SPI with DMA which can be found at the following location:

   

http://www.cypress.com/index.cfm?rID=38792

   

 

   

Looking at your comment, I have some concerns:

   

 

   

1) Since 16 bit words (2-Bytes each) is being received, and 4 such words will cause an interrupt, shouldn't the DMA be configured for 8 Bytes per Burst?

   

 

   

2) The status register can be read using Interrupt (ISR) or one of TD of the DMA Channel. (I am not sure of this method).

   

 

   

3) Can you upload your project so that we can debug the issue?

   

 

   

Regards

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