From ArmadeusWiki
Revision as of 12:14, 18 December 2009 by JulienB (Talk | contribs) (Usage)

Jump to: navigation, search

How to use the MAX9768 class D audio amplifier

Before installing the driver, the plateforme file (ie apf27-dev.c) has to be correctly modified to support the MAX9768 i2C chip.

Driver installation

 $ make linux26-menuconfig
Device Drivers--->
    Armadeus specific drivers ---> 
        <M> Armadeus Max9768 Audio Amplifier
 $ make 

Update the APF27 board with the new Linux kernel and rootfs.


  • Load the module:
# modprobe max9768
  • Power on the IC:
# echo 0 > /sys/class/i2c-dev/i2c-(x)/device/0-004(y)/shutdown

Where x is the I2C bus number (0 or 1) and y the i2C address of the chip

  • Mute off:
# echo 0 > /sys/class/i2c-dev/i2c-(x)/device/0-004(y)/mute
  • Change volume:
# echo 50 > /sys/class/i2c-dev/i2c-(x)/device/0-004(y)/volume

Remark: 0 <= volume value < 64