patch-2.1.109 linux/Documentation/sound/es1371

Next file: linux/Documentation/sound/mwave
Previous file: linux/Documentation/sound/es1370
Back to the patch index
Back to the overall index

diff -u --recursive --new-file v2.1.108/linux/Documentation/sound/es1371 linux/Documentation/sound/es1371
@@ -0,0 +1,56 @@
+ALaw/uLaw sample formats
+------------------------
+
+This driver does not support the ALaw/uLaw sample formats.
+ALaw is the default mode when opening a sound device
+using OSS/Free. The reason for the lack of support is
+that the hardware does not support these formats, and adding
+conversion routines to the kernel would lead to very ugly
+code in the presence of the mmap interface to the driver.
+And since xquake uses mmap, mmap is considered important :-)
+and no sane application uses ALaw/uLaw these days anyway.
+In short, playing a Sun .au file as follows:
+
+cat my_file.au > /dev/dsp
+
+does not work. Instead, you may use the play script from
+Chris Bagwell's sox-12.14 package (available from the URL
+below) to play many different audio file formats.
+The script automatically determines the audio format
+and does do audio conversions if necessary.
+http://home.sprynet.com/sprynet/cbagwell/projects.html
+
+
+Blocking vs. nonblocking IO
+---------------------------
+
+Unlike OSS/Free this driver honours the O_NONBLOCK file flag
+not only during open, but also during read and write.
+This is an effort to make the sound driver interface more
+regular. Timidity has problems with this; a patch
+is available from http://www.ife.ee.ethz.ch/~sailer/linux/pciaudio.html.
+(Timidity patched will also run on OSS/Free).
+
+
+MIDI UART
+---------
+
+The driver supports a simple MIDI UART interface, with
+no ioctl's supported.
+
+
+MIDI synthesizer
+----------------
+
+This soundcard does not have any hardware MIDI synthesizer;
+MIDI synthesis has to be done in software. To allow this
+the driver/soundcard supports two PCM (/dev/dsp) interfaces.
+
+There is a freely available software package that allows
+MIDI file playback on this soundcard called Timidity.
+See http://www.cgs.fi/~tt/timidity/.
+
+
+
+Thomas Sailer
+sailer@ife.ee.ethz.ch

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov