Re: 22.6us and ~10mips to create pink noise real time

On 19 May 2006 15:04:03 -0700, acannell@xxxxxxx wrote:

Okay I've got an Atmel AVR ATTiny13V. Runs off 3V, 100ns instruction
time. I am trying to generate 8 bit pink noise real time, cd quality,

For true "CD quality" you need a 16-bit sample.

so I have 1/44100 = 22.6us to generate each sample. I can write it in
assembler, or C, but I only have 1k of program memory so assembler is
probably the way to go here. Where should I start? Is it possible to
make a -3db/octave digital filter in assembler which takes random 8 bit
numbers and spits out pink noise?

At about 200 instructions per sample, 8-bit math and no hardware
multiply-accumulate function, I doubt you could do the filter.
If you use a D*** or one of the MSP430's that has the MAC add-on,
you MAY be able to do an appropriate FFT filter in real time. I think
I would go for one of the inexpensive but 'real' DSP's from TI or
Moto, er, Freescale. With these you can do 'true 16bit' and at least
get 12-bit resolution, or even do fixed-point "double precision"
32-bit and get better than 16-bit performance, easily done at the CD
sample rate.

.

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