[sdiy] WHICH PIC/UCONTROLLER should I buy today

[Tom Wiltshire]

On 9 Aug 2010, at 13:37, dan snazelle wrote:

> 
> "Regarding the generation of analog signals, you have plenty of options:
> - PWM on a digital pin (no external component needed except maybe a RC filter)"
> 
> am i mistaken in thinking that you cant use the PWM outputs for final audio signals (sine waves, white noise,etc)?or is there a simple way to convert this signal (isnt pwm a square wave output with changing duty cycle?)

Other people have dealt with exactly how this works. I'd just like to add that with a small 8-bit uP, you're unlikely to get a PWM frequency that can produce high audio frequencies at more than about 8-bit, tops.
You need a minimum 50KHz PWM frequency for full-range audio, and that implies a counter frequency of 12.8MHz at 8-bits resolution. Perhaps an AVR can do this, but the PICs use a counter rate that is a quarter of the master clock, and that implies a 5MHz maximum. Even if the AVR can do it, it's still only 8-bit audio - so think early 80s video games, not CD quality.

> ALSO...beyond the classic hal chamberlin book, are there any really good books on using AVR's or PICS for music/audio applications? OR just good books on modern AVR's or PICS?

If there are, I haven't found them. In fact, most of the PIC books I've seen are dreadful and have hideous examples of what I'd regard as extremely poor programming practice.

T.