Demand Peripherals     Robotics and Automation Made Easy

AAMP: Stereo 3 Watt Audio Amplifier

The AAMP peripheral controls the volume and mute on the AAMP card.

 

Hardware:

Each AAMP card has a PAM8408 stereo class-D audio amplifier. The mute and up/down volume controls for the PAM8408 are computer controlled through the FPGA pins of a BaseBoard4. The AAMP card also has a computer controlled LED. More information about the AAMP is available here: /cards/aamp.html

 

Resources:

volume : the volume of the amplifier as a number in the range of 1 to 32. Gain values are shown below.

          Volume Control (dB)
  value Gain    value Gain    value Gain         
   32    24      21    7.5     10   -10             
   31    22.5    20    6        9   -12             
   30    21      19    4.5      8   -14             
   29    19.5    18    3        7   -16             
   28    18      17    1.5      6   -18             
   27    16.5    16    0        5   -20             
   26    15      15   -1.5      4   -22               
   25    13.5    14   -3        3   -24              
   24    12*     13   -4.5      2   -26              
   23    10.36   12   -6        1   -80           
   22    9       11   -8        

enabled : a bit to enable (1) or disable (0) the amplifier. Note that a volume change can only occur when the amplifier is enabled. This resource works with dpset and dpget.

led : LED status as 1 (on) or 0 (off). This resource works with dpset and dpget.

 

Examples:

Set gain to 6 dB and turn the LED on.

   dpset aamp enabled 1
   dpset aamp volume 18
   dpset aamp led 1