That is a totally different issue. You were reading the same sample over and 
over again as opposed to increasing the sample rate by changing the clock 
divider, open delay, sample delay, etc. In any case, at 200ksps, each sample 
occurs every 5uS. How is a user space app going to process samples at 5uS? Even 
when you poll for the EOC with 8 channels configured, you still have to service 
the samples every 40uS and that is still not possible from a userspace app. 

My guess is the app you had was reading the same sample at a higher rate than 
1.5msps and then the scheduler switched out your app to service background 
tasks and then return a while later and then your app would read the same 
sample again. The average sample rate would then result in 1.5msps. Not a good 
idea. You should enable the channel ID to see when you miss samples. 

Regards,
John




> On Jun 20, 2016, at 5:49 PM, William Hermans <[email protected]> wrote:
> 
> So going back to what I said earlier. When using /dev/mem + mmap() yes, I was 
> (actually ) reading more than
>  200ksps from 7 channels simultaneously. For a total of somewhere around 
> 1.5Msps 
> 
> ***********BUT***********
> 
> Only 1 sample in ~8-9 per second was valid. So what I proved is possible is 
> completely different from what is accurate / possible for the AM335x's on die 
> ADC module.
> 
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