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AT91RM9200 SSC and I2S audio DAC

Started by Marcel-G January 18, 2004
Is there anybody who has used the SSC of the atmel AT91RM9200 in
master mode to control an audio DAC ?

I used the settings as described in the Atmel application note in my
device driver, but when a data to the driver and watch output on a
scope I see that left and right channels sometimes swap.

After this I did a test by writing only one short ( 16bit ) into the
SSC_THR and watch this data in relation to the frame sync signal, the
data is sometimes output when framesync = 0, and sometimes when
framesync = 1
I can not find any logic behaviour. 

Settings I used are as follows :
***TFMR***		
FSEDGE = 0
FSDEN = 0
FSOS = 1
FSLEN = 15
DATNB = 1
MSBF = 1
DATLEN = 15

***TCMR***
PERIOD=15
STDDLY=1
START=4
CKI=0
CKO=1
CKS=0

Any help would be apriciated, since I`m really ran out of ideas :-(

Marcel G
"Marcel-G" <marcel-g@xs4all.nl> wrote in message
news:1a53e44a.0401180633.1ddba5ea@posting.google.com...
> Is there anybody who has used the SSC of the atmel AT91RM9200 in > master mode to control an audio DAC ? > > I used the settings as described in the Atmel application note in my > device driver, but when a data to the driver and watch output on a > scope I see that left and right channels sometimes swap. > > After this I did a test by writing only one short ( 16bit ) into the > SSC_THR and watch this data in relation to the frame sync signal, the > data is sometimes output when framesync = 0, and sometimes when > framesync = 1 > I can not find any logic behaviour. > > Settings I used are as follows : > ***TFMR*** > FSEDGE = 0 > FSDEN = 0 > FSOS = 1 > FSLEN = 15 > DATNB = 1 > MSBF = 1 > DATLEN = 15 > > ***TCMR*** > PERIOD=15 > STDDLY=1 > START=4 > CKI=0 > CKO=1 > CKS=0 > > Any help would be apriciated, since I`m really ran out of ideas :-( >
Contact at91support at atmel dot com for direct contact with the Apps Lab. -- Best Regards Ulf at atmel dot com These comments are intended to be my own opinion and they may, or may not be shared by my employer, Atmel Sweden.