envy
— VIA Envy24
audio device
envy* at pci?
audio* at envy?
midi* at envy?
The envy
driver supports sound cards based
on VIA Envy24 and Envy24HT PCI chips. The following sound cards are
currently supported:
- Dynex DX-SC51
- ESI Julia
- M-Audio Delta 1010, 1010LT, 66 and 44
- M-Audio Audiophile 2496
- M-Audio Revolution 5.1
- M-Audio Audiophile 192k
- Terratec EWX 24/96
- VIA Tremor 5.1
The chip features a digital mixer that routes and mixes the
streams below as follows:
inputs
- There are 8 streams corresponding to data received by the device from the
codecs. They are labelled line0 –
line7 in the
mixer(4) interface.
outputs
- There are 8 streams corresponding to data sent by the device to the
codecs. They are labelled line0 –
line7. Each of them can be individually configured
to use any of the external inputs or its corresponding playback stream as
source. Additionally, outputs line0 and
line1 can be configured to use
mon0 or mon1 as sources.
monitor
- There are 2 streams that can be configured to contain any linear
superposition of any of the 10 playback and 10 external input streams.
They are labelled mon0 and
mon1. From the mixer's point of view they are input
streams, so they can be used as sources of output streams. This feature is
specific to Envy24 based cards.
playback
- There are 10 streams corresponding to samples transferred from the host to
the device. They are labelled play0 –
play9. From the mixer's point of view they are input
streams, so they are usable as sources of output streams.
record
- There are 12 streams corresponding to samples transferred from the device
to the host. They are not controllable by the mixer. Streams 0 to 7 are
hardwired to external inputs line0 –
line7 and streams 10 and 11 are hardwired to
mon0 and mon1.
Both playback and record use linear encoding. Samples are
represented by 32-bit signed numbers in little endian order. Only the first
24 most significant bits are used. On Envy24-based cards, playback uses 10
channels and record uses 12 channels, while on Envy24HT-based cards the
number of streams depend on the number of codecs physically present on the
card.
The envy
driver first appeared in
OpenBSD 4.3.
S/PDIF transmitter/receiver is not supported.
Ring buffer sizes are limited to 64kB, which can be limiting at
high sample rates.