STM CircleOS forum / audio output level on Primer2

mdce · 2009-12-21 12:53:41

Hi,
I mesured 0.13 Vpp at full scale and maximum volume on the headphone jack.
How can I get a higher level?

yrt · 2009-12-25 16:48:24

Hi,

The maximum volume is limited by the CircleOS in the function "AUDIO_Inc_Volume" (minimum attenuation = -4 dB), and in the function " AUDIO_Set_Volume" for the headphones, at the double attenuation of the loudspeaker's one.

You can modify the following line in "circle.h"
#define AUDIO_MIN_ATTENUATION 4 // Min attenuation in dB
or modify the "AUDIO_Set_Volume" function as you want.

Yves

mdce · 2009-12-27 17:24:13

Thank you.
I will modify audio.c
The loudspeaker level is currently set from -2 dB to -24 dB in 2 dB steps, and the headphone level from -24 dB to -40 dB in 4 dB steps !!!!

Manuel

# 1 2009-12-21 12:53:41 audio output level on Primer2

audio output level on Primer2

# 2 2009-12-25 16:48:24 audio output level on Primer2

Re: audio output level on Primer2

# 3 2009-12-27 17:24:13 audio output level on Primer2

Re: audio output level on Primer2

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