PSoC 5 DAC Bug

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Anonymous
Not applicable

Hi,

   

 

   

as you can read in the DAC Api, with PSoC 5 you have to write the DAC Value to the register twice. I think because of a bug.

   

 

   

So what is the solution when working with DMA? I have to send out two functions (saved in two arrays) with two DACs and sample simultanous with SAR ADC. So at this time there are 4 DMA channels in my project.

   

 

   

Sadly I see that the DACs have sometimes glitchy output. For testing purpose I added two more DMA Channels writing the same data twice to the first ones into the DAC. The output is more stable but I had some more problems in the system.

   

 

   

What is die correct solution when working with DMA and DACs under PSoC 5 (production?)

   

 

   

Bye

   

Franz

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3 Replies
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

In the C-sources you can still see that a second write is made for PSoC5 devices except for the PSoC5LP version.

   

Interesting, I never assumed or experienced an issue with the DAC and in the appnotes concerning ADC -> DMA -> DAC there was never anything special for PSoC5 mentioned.

   

 

   

Bob

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Anonymous
Not applicable

 I've used hardware strobe synchronous to the DMA strobe. That works without glitches.

   

 

   

Thanks!

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Anonymous
Not applicable

 Ohh.. Thanks for pointing this out... I was not aware of this bug before.

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