eap(4) - NetBSD Manual Pages

EAP(4)                  NetBSD Kernel Interfaces Manual                 EAP(4)


NAME

     eap -- AudioPCI audio device driver


SYNOPSIS

     eap*    at pci? dev ? function ?
     options EAP_USE_BOTH_DACS

     audio*  at audiobus?
     joy*    at eap?
     midi*   at eap?


DESCRIPTION

     The eap driver provides support for the Ensoniq AudioPCI and Creative
     Labs SoundBlaster PCI series of audio cards.  All models based on the
     ES1370, ES1371, and ES1373 chips are supported.

     By specifying:

           options EAP_USE_BOTH_DACS

     a second audio device is attached.  This can be used for audio output
     simultaneously with the primary DAC.  You can use it simply by directing
     audio output to the additional /dev/audioX device associated with it.


SEE ALSO

     ac97(4), audio(4), joy(4), midi(4), pci(4)


HISTORY

     The eap device driver appeared in NetBSD 1.4.


CAVEATS

     The joystick port hardware works by emulating a legacy isa(4) joystick
     port, bypassing the pci(4) bus method for address allocation.  This is
     unlikely to work on PCI busses other than the primary one.  There is also
     a possibility for conflicts with real ISA devices because the PCI bus is
     probed before ISA.  Use with caution.

     The EAP_USE_BOTH_DACS option is rather redundant after the introduction
     of the in-kernel audio mixer, and may be removed in a future release.  It
     is possible that it could be used to accelerate mixing streams by taking
     advantage of the hardware's features, but currently the additional
     (small) overhead of the kernel mixer is impossible to bypass, since
     NetBSD no longer allows userspace software to write directly to audio
     hardware.  The eap hardware only features one clock, so generally the
     second audio device must be configured in the same way as the first.

NetBSD 10.99                     May 16, 2024                     NetBSD 10.99