AVR-Chat

----- Original Message ----- 
From: "Marc R.J. Brevoort" <mrjb@dnd.utwente.nl>
To: <AVR-Chat@yahoogroups.com>
Sent: Sunday, December 27, 2009 2:56 PM
Subject: [AVR-Chat] ATtiny2313 audio


> Hello all,
>
> I've been programming the ATtiny2313 to generate
> monophonic, square wave beeps (you could call it
> 'music' with a bit of imagination). The code was
> based mostly around the delay function.
>
> I'd like to try polyphonic audio now- still using
> simple square waves. As the time needed per
> calculation is now variable and/or the wave forms
> more complex, I can no longer count on the delay
> function. So instead, I wanted to make the code
> interrupt-driven.
>
> However, I don't seem to manage to get even nearly
> enough interrupts per second to generate audio.
> I would need about 16000 interrupts per second.
> The ATtiny2313 is running at 8 MHz. Is the 2313
> simply too slow for the task? Surely if a lowly
> 286 could feed audio to a DAC, the ATtiny2313
> should be able to handle the load as well?

I've generated sine waves using a software DDS up to 200 kHz or so, with a 
12 MHz Tiny2313.

Leon