[sdiy] WHICH PIC/UCONTROLLER should I buy today

[dan snazelle]

"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?)

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?


thanks so much, my inbox is filling up with really great answers!!!!





On Aug 9, 2010, at 8:19 AM, Olivier Gillet wrote:

> Hi,
> 
> Leaving aside the ARM uC which are probably overkill for what you want
> to do, there are two main choices: 8-bits AVR and PICs, for which
> people are fighting holy wars. Both families have roughly the same
> computational power, I/O capabilities, are available in all packages
> from DIP to centipedes, are cheap, and have vibrant communities from
> which you can get help.
> 
> Some reasons to use AVRs:
> - Thanks to the Arduino project, the barrier to entry in the AVR world
> is very, very low: a $20 Arduino clone + the pre-bundled Arduino
> development environment and you can find yourself running code in
> matters of minutes. There's a large community very supportive of
> beginners, and tons of code samples to reuse. You could get trapped in
> it.
> - The compiler and toolchain are based on gcc/libtools -- no
> proprietary, wacky, compilers ; and if you're used to develop on other
> platforms the workflow can be exactly the same.
> - Relatively "sane" assembly language.
> 
> Some reasons to use PICs:
> - The high-end PICs (dsPICs) can do much more stuff than the high-end
> AVRs, and can run at faster clock rates - useful if you want to do
> audio-rate signal processing/generation.
> - You can reuse bits from the MIDIbox projects.
> 
> 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)
> - R2R DAC (2 resistors per bit, one I/O pin per bit)
> - Parallel DAC chip, one I/O pin per bit
> - SPI DAC chip (eg: dual 12 bits DAC: MCP4922), 3 I/O pins dedicated
> to hardware SPI.
> - I2C DAC chip (have never used one), 2 I/O pins dedicated to hardware I2C.
> 
> Olivier
>