AnsweredAssumed Answered

DAC to Audio Out

Question asked by dreschel.william on Dec 13, 2011
Latest reply on Feb 12, 2012 by bulmer.g
Has anyone been able to use the DAC output (PA4) to generate sound on the headphone port? It seemed like a trivial thing to do, set up the CS43L22 in analog pass-thru mode... but that was 3 days ago. I generate a 3.5kHz sine wave on PA4 and can scope it all the way to the Cirrus CS43L22 but nothing I have programmed to it over the I2C has worked. I even downloaded the scripts to Cirrus' eval board and mimic'd them in my code's I2C comands and that did not work.
I know the CS43L22 is alive because I was able to compile and run an abbreviated vesion of the Audio_playback_and_record demo. I tried modifying  waveplayer.c to choose the AUDIO_INTERFACE_DAC... no luck. Any insights would be appreciated.
By the way, the way the Discovery is configured (2.5V on the CS43L22 and 3.3V on the STM32F4 DAC) appears to apply a voltage above the max rating on the analog in (AIN1A & AIN1B) pin of the CS43L22... maybe I accidently smoked the analog input by using the DAC at full range...
THANKS...

Outcomes