Lpc2000

Is it safe to assume that mono audio can be generated by using only
one SPI port?

Gary

--- In lpc2000@yahoogroups.com, "ian.scanlon" <scanlon.design@...> wrote:
>
> ** oops **  Misread the docs on /WS (word select).  But the concept 
> is still the same with two slaves and externally generated /ws and 
> clock.  Very simple if you can use both SPI ports.
> 
> 
> --- In lpc2000@yahoogroups.com, "ian.scanlon" <scanlon.design@> 
> wrote:
> >
> > I have done something similar.  I2S from uC to DAC looks like 
> (quick 
> > review) simple SPI interface.
> > 
> > You need to create a system with two slave devices and an external 
> > source for clock and /select. Set SPI port slave, DAC already slave.
> > 
> > Data:  Connect directly- uC slave out to DAC in
> > Clock: External clock source (timer output ?) connects to both uC 
> and 
> > DAC. Used to clock the data from the SPI port to the DAC.
> > /select: Use timer fed by clock(above) with period set to sample 
> > output rate and pulse width-low to count the number of bits in each 
> > sample.  
> > 
> > Now you just need to keep the SPI buffer full - either interrupt or 
> > polled.  The data is transfer from the SPI port (as slave) to the 
> DAC 
> > clocked by the clock and /select you have supplied.
> > 
> > Philips has a document "I2S Bus Specification" that may be 
> helpful,  
> > don't know the real .pdf filename.
> > 
> > 
> > Ian
> > 
> > --- In lpc2000@yahoogroups.com, "ee_gary" <ee_gary@> wrote:
> > >
> > > I'm interested in this as well.  Has anyone successfully 
> > communicated
> > > with an I2S DAC using SPI?
> > > 
> > > Gary
> > > 
> > > --- In lpc2000@yahoogroups.com, "croquettegnu" <croquettegnu@> 
> > wrote:
> > > >
> > > > Thanks but this link concerns at91 product !
> > > > you mean there are no peripherals dedicated to I2S or AC97 in 
> the
> > > LPC ???
> > > > 
> > > > Thanks
> > > > --- In lpc2000@yahoogroups.com, "ian.scanlon" <scanlon.design@> 
> > wrote:
> > > > >
> > > > > See:
> > > > > http://www.atmel.com/dyn/resources/prod_documents/doc2646.pdf
> > > > > 
> > > > > to implement in CPLD.
> > > > > 
> > > > > You can also set the SSP as slave and use internal timers and 
> > some 
> > > > > external logic to generate required signals and timing.
> > > > > 
> > > > > Ian
> > > > > 
> > > > > 
> > > > > --- In lpc2000@yahoogroups.com, "croquettegnu" 
> <croquettegnu@> 
> > wrote:
> > > > > >
> > > > > > I need to use the I2S protocol and I am looking for what 
> would
> > > be the
> > > > > > most appropriate peripheral to deal with ???
> > > > > > 
> > > > > > Is AC97 possible too ?
> > > > > > 
> > > > > > Thanks a lot !
> > > > > >
> > > > >
> > > >
> > >
> >
>