Picomod7 ALSA

  • Hi, how do I access the sound device? I have inlcuded the ALSAlib. In my FS there's a /proc/asound directory. Inside there's a card0 folder. The hardware is identified as pm7tlv320. The question is: what is the name of the device? With the ALSAlib there comes a test program named pcm that should generate a sinus wave to the sound output. Here I have to add the device name e.g. ./pcm -Dhw:0,0. All devices I tried did not work.


    (_snd_pcm_hw_open) Invalid value for card
    Playback open error: No such file or directory


    In my /dev folder there's no device that looks like sound.


    Thanks in advance.

  • you need these device-nodes in /dev/snd:


    Code
    1. crw-r--r-- 1 root root 116, 0 Mar 15 2012 controlC0
    2. crw-r--r-- 1 root root 116, 24 Mar 15 2012 pcmC0D0c
    3. crw-r--r-- 1 root root 116, 16 Mar 15 2012 pcmC0D0p
    4. crw-r--r-- 1 root root 116, 33 Mar 15 2012 timer


    with zImage_PicoMOD7_V0.1 you should see in the bootlog:


    Code
    1. ALSA device list:
    2. #0: pm7-tlv320 (tlv320aic23)

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.

  • I have these lines in bootlog:

    Code
    1. ALSA device list:
    2. #0: pm7-tlv320 (tlv320aic23)


    but no /dev/snd directory.


    Here I send my #ls -lah output:


  • Code
    1. mkdir /dev/snd
    2. mknod /dev/snd/controlC0 c 116 0
    3. ...


    If you use v0.1 root-file-system these are per default set.

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.