I found the answer, for those trying to do this. Change this line ioctl(mixer_fd, SOUND_MIXER_WRITE_VOLUME, &vol)
to ioctl(mixer_fd, SOUND_MIXER_WRITE_PCM, &vol) On Sat, Jun 21, 2014 at 4:48 AM, John Syn <[email protected]> wrote: > > From: Charles Kerr <[email protected]> > Reply-To: "[email protected]" <[email protected]> > Date: Friday, June 20, 2014 at 6:36 PM > To: "[email protected]" <[email protected]> > Subject: [beagleboard] Setting volume from C++ on the audio cape (Rev B1) > > I have the following code which I think should set the volume on the audio > cape to 100% > > Use alsamixer to experiment with the various settings. After that, it will > be easier to work out how to do this programatically. > > Regards, > John > > > int32_t mixer_fd=0; > > mixer_fd=open("/dev/mixer", O_WRONLY); > > if (mixer_fd>0) > > { > > int vol=0x6464; > > if (ioctl( > mixer_fd, SOUND_MIXER_WRITE_VOLUME, &vol)==-1) > > { > > std::cout <<"Error setting volume"<<std::endl; > > } > > close(mixer_fd); > > } > > > However, the volume is still barely audible. Is there something else that > needs to be done? > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > > For more options, visit https://groups.google.com/d/optout. > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to a topic in the > Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/rTsdO11BIrY/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
