Hi Andrea!

Am Mittwoch, 30. März 2016 23:07:55 UTC+2 schrieb 
[email protected]:
>
> My mistake was to build only the FreeBasic library and not the one in the 
> folder `c_wrapper`
>

No mistake, a lucky find. Just use the matching compiler.
 

> I have another question: I'm trying to read from the ADC the sound from a 
> microphone. So I would like to acquire data at 44100Hz
> In order to achive this result I follow your documentation so I've 
> configured the ADC as follow
>
> pruio_config(io, 2, 0x1FE, 0x22675, 4)
>>
>
> I put 22675 as a hexadecimal value because if I put it as a decimal number 
> the library continue to give me the error
>
> config failed (sample rate too big)
>
> Can you, kindly, put me in the right direction to achieve my goal?
>

It's too less code to give detailed advices. What I can see:

   - You specify only 2 samples (second parameter). That's too less. Your 
   ARM code isn't fast enough to fetch the data value by value with 
   appropriate timing.
   - You set 0x1FE as step mask (third parameter). Why do you need steps 1 
   to 8 (defaults to AIN-0 to AIN-7)? The maximum sampling rate for 8 channels 
   is 25 kHz (= 200 kHz / 8).
   - Your sampling rate (fourth parameter) is 7096.3 Hz (= 1e9 / 0x22765, 
   or in decimal 1e9 / 140917). It's not possible to sample at exactly 44100 
   Hz, but 44101,43 Hz is possible by using 22765 (= 0x5893) as fourth 
   parameter.

So from my point of view you should

   - Adapt the step mask to the necessary channels (= steps). The correct 
   value depends on your wiring and step configuration (code is missing).
   - Increase the number of samples (use all ERam: 131070 for one step or 
   65536 for two steps, when using default configuration of driver uio_pruss).
   - Adapt the sampling rate (to 0x5893 = 22765).

Then use RB mode to fetch the samples (and output them to a file or 
evaluate them directly) or MM mode for a single shot (~ 3 s recording for 1 
step, 1.5 s recording for 2 steps).

BR 

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