Forums - DAC output goes to zero after an ADC read

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DAC output goes to zero after an ADC read
Join Date: 14 Feb 17
Posts: 2
Posted: Tue, 2017-02-14 07:58


Title kind of says it all.

I have a DAC that i set to a specifiy voltage on AIO[0].  Later on I do a ADC read on a different AIO pin(AIO[1]).  I notice that the voltage from the DAC output goes to zero right after an ADC read. Setting up break points in the code showed me this. If i get rid of the ADC read the DAC output is always there and stable. But I need the ADC read.  I can't figure out what is going on or is this how it works?  



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Dr. Nissim Zur
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Join Date: 6 Jun 16
Location: Skype: nissim.test CSR1010 External design house
Posts: 235
Posted: Tue, 2017-02-14 10:07

There is no 3 AIO and no 3 DAC. 
Only one unit that server all  3 AIO and no 3 DAC. 

I do not know what CSR present that as defiant hardware units. 

So any AIO read  will rest all other AIO and DAC

Any ADC will do the same to other AIO and DAC

It's a kind of selector of one internal HD unit


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Join Date: 14 Feb 17
Posts: 2
Posted: Tue, 2017-02-14 12:26

Thanks for your input.  

But there are three AIO pins 0, 1 ,2.  Any of them pins can be used to set a DAC level or be used for an ADC input.

So your point really is its a crappy all in one ADC / DAC module .  That ANY AIO that is used will reset the other AIO pins.

I wish they stated this in their spec.  It's trial and error with them.

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