[sdiy] (OT)help processing realtime audio on Arduino?

[Stewart Pye]

Hi Dan,

Have you looked at the AVR instruction set? I think it's more detailed 
than what's in the datasheets...
www.atmel.com/dyn/resources/prod_documents/doc0856.pdf


Stew.





dan snazelle wrote:
> can anyone recommend a source for understanding things like CBI, SBI, timers, etc?
> other than just the AVR datasheet? are these universal terms which i will find outside of the avr world? I did buy a book that aaron lanterman recommended on more general programming concepts
> but I HQBWNR 																
>
>
> i suppose that just like all the arduino terms i have been starting to learn, this code wouldnt seem as hard if i knew what some of the stuff meant.
> but right now, there is little in that article's code that is obvious.
>
> everyone recommends this article though. i played around with the actual code on saturday....seeing what it could do. interesting...however it was certainly not high fi
>
>
> i am still trying to figure out if this chip is going to be able to handle any of the tasks i want it to handle or if i should start looking into something more powerful like a dspic or a 
> 16 or 32 bit pic.
>
> but this seems hard enough for now and certainly fun!!!
>
> thanks
>
>
>
>
>
> On Feb 1, 2011, at 3:19 PM, Olivier Gillet wrote:
>
>   
>>> I had a read-through of that LAB3 article, and it's not *too* bad. Although I didn't understand why the set a timer up at 62.5KHz and then only used every other interrupt to read an audio sample. Perhaps the ADC is slow.
>>>       
>> The timer pre-scaler is coarse, it is set by increments of 8 IIRC.
>> Though you can use phase accurate PWM instead of fast PWM in which
>> case the interrupt rate is divided by two and you'll get 31.25kHz. See
>> the ATMega328p datasheet.
>>
>>     
>>> Maybe i need a book not on arduino but on the AVR!
>>>       
>> The arduino library (digitalWrite, analogRead) has a huge overhead
>> (these are functions - run-time abstractions - not macro or templates
>> - compile-time abstractions) and favors blocking I/O. It is not
>> appropriate for audio coding, so you have to dig into the "low level"
>> stuff.
>>
>>     
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>
>