mirror of
https://github.com/torvalds/linux.git
synced 2024-11-22 04:02:20 +00:00
0982e519df
They are sufficiently different from Sound Blasters. Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de> Link: https://lore.kernel.org/r/20230825222157.170978-3-oswald.buddenhagen@gmx.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
227 lines
8.7 KiB
ReStructuredText
227 lines
8.7 KiB
ReStructuredText
==================================================
|
|
E-MU Digital Audio System mixer / default DSP code
|
|
==================================================
|
|
|
|
This document covers the E-MU 0404/1010/1212/1616/1820 PCI/PCI-e/CardBus
|
|
cards.
|
|
|
|
These cards use regular EMU10K2 (SoundBlaster Audigy) chips, but with an
|
|
alternative front-end geared towards semi-professional studio recording.
|
|
|
|
This document is based on audigy-mixer.rst.
|
|
|
|
|
|
Hardware compatibility
|
|
======================
|
|
|
|
The EMU10K2 chips have a very short capture FIFO, which makes recording
|
|
unreliable if the card's PCI bus requests are not handled with the
|
|
appropriate priority.
|
|
This is the case on more modern motherboards, where the PCI bus is only a
|
|
secondary peripheral, rather than the actual arbiter of device access.
|
|
In particular, I got recording glitches during simultaneous playback on an
|
|
Intel DP55 board (memory controller in the CPU), but had success with an
|
|
Intel DP45 board (memory controller in the north bridge).
|
|
|
|
The PCI Express variants of these cards (which have a PCI bridge on board,
|
|
but are otherwise identical) may be less problematic.
|
|
|
|
|
|
Driver capabilities
|
|
===================
|
|
|
|
This driver supports only 16-bit 44.1/48 kHz operation. The multi-channel
|
|
device (see emu10k1-jack.rst) additionally supports 24-bit capture.
|
|
|
|
A patchset to enhance the driver is available from `a GitHub repository
|
|
<https://github.com/ossilator/linux/tree/ossis-emu10k1>`_.
|
|
Its multi-channel device supports 24-bit for both playback and capture,
|
|
and also supports full 88.2/96/176.4/192 kHz operation.
|
|
It is not going to be upstreamed due to a fundamental disagreement about
|
|
what constitutes a good user experience.
|
|
|
|
|
|
Digital mixer controls
|
|
======================
|
|
|
|
Note that the controls work as attenuators: the maximum value is the neutral
|
|
position leaving the signal unchanged. Note that if the same destination is
|
|
mentioned in multiple controls, the signal is accumulated and can be clipped
|
|
(set to maximal or minimal value without checking for overflow).
|
|
|
|
Explanation of used abbreviations:
|
|
|
|
DAC
|
|
digital to analog converter
|
|
ADC
|
|
analog to digital converter
|
|
LFE
|
|
low frequency effects (used as subwoofer signal)
|
|
IEC958
|
|
S/PDIF
|
|
FX-bus
|
|
the EMU10K2 chip has an effect bus containing 64 accumulators.
|
|
Each of the synthesizer voices can feed its output to these accumulators
|
|
and the DSP microcontroller can operate with the resulting sum.
|
|
|
|
name='Clock Source',index=0
|
|
---------------------------
|
|
This control allows switching the word clock between interally generated
|
|
44.1 or 48 kHz, or a number of external sources.
|
|
|
|
Note: the sources for the 1616 CardBus card are unclear. Please report your
|
|
findings.
|
|
|
|
name='Clock Fallback',index=0
|
|
-----------------------------
|
|
This control determines the internal clock which the card switches to when
|
|
the selected external clock source is/becomes invalid.
|
|
|
|
name='DAC1 0202 14dB PAD',index=0, etc.
|
|
---------------------------------------
|
|
Output attenuation controls. Not available on 0404 cards.
|
|
|
|
name='ADC1 14dB PAD 0202',index=0, etc.
|
|
---------------------------------------
|
|
Input attenuation controls. Not available on 0404 cards.
|
|
|
|
name='Optical Output Mode',index=0
|
|
----------------------------------
|
|
Switches the TOSLINK output port between S/PDIF and ADAT.
|
|
Not available on 0404 cards (fixed to S/PDIF).
|
|
|
|
name='Optical Input Mode',index=0
|
|
---------------------------------
|
|
Switches the TOSLINK input port between S/PDIF and ADAT.
|
|
Not available on 0404 cards (fixed to S/PDIF).
|
|
|
|
name='PCM Front Playback Volume',index=0
|
|
----------------------------------------
|
|
This control is used to attenuate samples from left and right front PCM FX-bus
|
|
accumulators. ALSA uses accumulators 8 and 9 for left and right front PCM
|
|
samples for 5.1 playback. The result samples are forwarded to the DSP 0 & 1
|
|
playback channels.
|
|
|
|
name='PCM Surround Playback Volume',index=0
|
|
-------------------------------------------
|
|
This control is used to attenuate samples from left and right surround PCM FX-bus
|
|
accumulators. ALSA uses accumulators 2 and 3 for left and right surround PCM
|
|
samples for 5.1 playback. The result samples are forwarded to the DSP 2 & 3
|
|
playback channels.
|
|
|
|
name='PCM Side Playback Volume',index=0
|
|
---------------------------------------
|
|
This control is used to attenuate samples from left and right side PCM FX-bus
|
|
accumulators. ALSA uses accumulators 14 and 15 for left and right side PCM
|
|
samples for 7.1 playback. The result samples are forwarded to the DSP 6 & 7
|
|
playback channels.
|
|
|
|
name='PCM Center Playback Volume',index=0
|
|
-----------------------------------------
|
|
This control is used to attenuate samples from the center PCM FX-bus accumulator.
|
|
ALSA uses accumulator 6 for center PCM samples for 5.1 playback. The result samples
|
|
are forwarded to the DSP 4 playback channel.
|
|
|
|
name='PCM LFE Playback Volume',index=0
|
|
--------------------------------------
|
|
This control is used to attenuate samples from the LFE PCM FX-bus accumulator.
|
|
ALSA uses accumulator 7 for LFE PCM samples for 5.1 playback. The result samples
|
|
are forwarded to the DSP 5 playback channel.
|
|
|
|
name='PCM Playback Volume',index=0
|
|
----------------------------------
|
|
This control is used to attenuate samples from left and right PCM FX-bus
|
|
accumulators. ALSA uses accumulators 0 and 1 for left and right PCM samples for
|
|
stereo playback. The result samples are forwarded to the virtual stereo mixer.
|
|
|
|
name='PCM Capture Volume',index=0
|
|
---------------------------------
|
|
This control is used to attenuate samples from left and right PCM FX-bus
|
|
accumulators. ALSA uses accumulators 0 and 1 for left and right PCM.
|
|
The result is forwarded to the standard capture PCM device.
|
|
|
|
name='Music Playback Volume',index=0
|
|
------------------------------------
|
|
This control is used to attenuate samples from left and right MIDI FX-bus
|
|
accumulators. ALSA uses accumulators 4 and 5 for left and right MIDI samples.
|
|
The result samples are forwarded to the virtual stereo mixer.
|
|
|
|
name='Music Capture Volume',index=0
|
|
-----------------------------------
|
|
These controls are used to attenuate samples from left and right MIDI FX-bus
|
|
accumulator. ALSA uses accumulators 4 and 5 for left and right MIDI samples.
|
|
The result is forwarded to the standard capture PCM device.
|
|
|
|
name='Front Playback Volume',index=0
|
|
------------------------------------
|
|
This control is used to attenuate samples from the virtual stereo mixer.
|
|
The result samples are forwarded to the DSP 0 & 1 playback channels.
|
|
|
|
name='Surround Playback Volume',index=0
|
|
---------------------------------------
|
|
This control is used to attenuate samples from the virtual stereo mixer.
|
|
The result samples are forwarded to the DSP 2 & 3 playback channels.
|
|
|
|
name='Side Playback Volume',index=0
|
|
-----------------------------------
|
|
This control is used to attenuate samples from the virtual stereo mixer.
|
|
The result samples are forwarded to the DSP 6 & 7 playback channels.
|
|
|
|
name='Center Playback Volume',index=0
|
|
-------------------------------------
|
|
This control is used to attenuate samples from the virtual stereo mixer.
|
|
The result samples are forwarded to the DSP 4 playback channel.
|
|
|
|
name='LFE Playback Volume',index=0
|
|
----------------------------------
|
|
This control is used to attenuate samples from the virtual stereo mixer.
|
|
The result samples are forwarded to the DSP 5 playback channel.
|
|
|
|
name='Tone Control - Switch',index=0
|
|
------------------------------------
|
|
This control turns the tone control on or off. The samples forwarded to
|
|
the DSP playback channels are affected.
|
|
|
|
name='Tone Control - Bass',index=0
|
|
----------------------------------
|
|
This control sets the bass intensity. There is no neutral value!!
|
|
When the tone control code is activated, the samples are always modified.
|
|
The closest value to pure signal is 20.
|
|
|
|
name='Tone Control - Treble',index=0
|
|
------------------------------------
|
|
This control sets the treble intensity. There is no neutral value!!
|
|
When the tone control code is activated, the samples are always modified.
|
|
The closest value to pure signal is 20.
|
|
|
|
name='Master Playback Volume',index=0
|
|
-------------------------------------
|
|
This control is used to attenuate samples for all DSP playback channels.
|
|
|
|
name='EMU Capture Volume',index=0
|
|
----------------------------------
|
|
This control is used to attenuate samples from the DSP 0 & 1 capture channels.
|
|
The result is forwarded to the standard capture PCM device.
|
|
|
|
name='DAC Left',index=0, etc.
|
|
-----------------------------
|
|
Select the source for the given physical audio output. These may be physical
|
|
inputs, playback channels (DSP xx, specified as a decimal number), or silence.
|
|
|
|
name='DSP x',index=0
|
|
--------------------
|
|
Select the source for the given capture channel (specified as a hexadecimal
|
|
digit). Same options as for the physical audio outputs.
|
|
|
|
|
|
PCM stream related controls
|
|
===========================
|
|
|
|
These controls are described in audigy-mixer.rst.
|
|
|
|
|
|
MANUALS/PATENTS
|
|
===============
|
|
|
|
See sb-live-mixer.rst.
|