[sdiy] Microchip DSP kit $60

[Scott Gravenhorst]

Eric Brombaugh <ebrombaugh at earthlink.net> wrote:
>Scott Gravenhorst wrote:
>> "Barry Klein" <Barry.L.Klein at wdc.com> wrote:
>>> Supposedly new DSP dev. kit for $60.
>>> Looks like a decent kit for that much $$.
>>> Anyone doing anything with it?
>>> 
>http://microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en534506

>> > Barry, > > Thank you for this. > > DSP people - is 16 KB RAM 
>big/small/midsize? > > What sort of applications can we fit in 
>this? > > Also, what does this mean: > "Low cost audio capture 
>and play back circuitry using the 12 bit ADC and PWM Audio" > > 
>Specifically, "PWM" - pulse width modulation - is that how they 
>make audio out? Not sure > what the implications for that are 
>with respect to things like aliasing, noise and > distortion. > > 
>Max sample rate of 48KHz isn't stellar, but it's usable. 
>
>Microchip dsPIC processors are fairly nice little parts. They're 
>relatively inexpensive, available in DIP packages, have a decent 
>instruction set that's easy to remember and come with a good complement 
>of peripherals. Software development tools are free and the programming 
>hardware is fairly inexpensive.
>
>Downsides are that they're 16-bit processors so it's difficult to do 
>excellent audio DSP with them and the various revs of the parts have 
>interesting 'undocumented features' which sometimes require a bit of 
>research to work around.
>
>Overall I like them. You can do some amazing stuff with them if you are 
>prepared to bang your head against the wall a little bit.
>
>This new development system is probably a great way to get your feet wet 
>with the dsPIC in audio applications. While 48kHz is a decent sample 
>rate, I wouldn't expect great things from 12-bit converters and PWM 
>output though. For studio-quality audio, some dsPICs have an I2S codec 
>interface that's much better.

Much agreement about this - especially the point about 16 bits.  One thing I like
about doing DSP in an FPGA is that calculations can be as wide as you want them.

What about the 16K RAM?  Is that DSP code RAM?  Data RAM such as for delay line use?



-- ScottG

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-- Scott Gravenhorst
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