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Re: iTunes - Can I create multiple profiles?



Simon D. Williams wrote:
Tristan Mumford wrote:

IIRC iPods can also accept things in plain .wav format. Just write a simple
program to spit out a header and dynamically generate the music in pure
8-bit digital!

Might me completely senseless but it sounds like fun


I wonder if CFFA is fast enough to allow "streaming" playback of .wav
files via DAC522. 8-bit 11KHz mono files are comparable in size to MP3
and sound quality really isn't that bad... someone clever should
seriously look into this ;-)

A fundamental problem is that DAC522 *completely* occupies the
processor while playing, so there would be no way to read in another
memory-load without stopping the playing.  This is true even for DMA,
since DMA steals processor memory cycles and would disturb the timing
of DAC522.

Anything that must be done while DAC522 is playing must be carefully
integrated into DAC522, maintaining cycle-accurate timing--and the
total budget for additional code (beyond what is needed to fetch
and prepare the next sample and test for the end) is almost nil.

This constraint is what made CRATE.SYNTH and RT.SYNTH so interesting.
;-)

-michael

NadaNet networking for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

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