Lpc2000

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 !

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 !
>

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 !
> >
>

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 !
> > >
> >
>

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 !
> > > >
> > >
> >
>

** 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 !
> > > > >
> > > >
> > >
> >
>

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 !
> > > > > >
> > > > >
> > > >
> > >
> >
>

Yes. When /ws is 1 no data will be transmitted from SPI as slave. In 
the case of I2S you will want the duty cycle of /ws to be 50% and the 
period 2x the number of data bits. 


Ian



--- In lpc2000@yahoogroups.com, "ee_gary" <ee_gary@...> wrote:
>
> 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 !
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
>