| Recording |
| --------- |
| |
| Recording does not work on the author's card, but there |
| is at least one report of it working on later silicon. |
| The chip behaves differently than described in the data sheet, |
| likely due to a chip bug. Working around this would require |
| the help of ESS (for example by publishing an errata sheet), |
| but ESS has not done so far. |
| |
| Also, the chip only supports 24 bit addresses for recording, |
| which means it cannot work on some Alpha mainboards. |
| |
| |
| /proc/sound, /dev/sndstat |
| ------------------------- |
| |
| /proc/sound and /dev/sndstat is not supported by the |
| driver. To find out whether the driver succeeded loading, |
| check the kernel log (dmesg). |
| |
| |
| 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 (or later, 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 |
| ---------------- |
| |
| The card has an OPL compatible FM synthesizer. |
| |
| Thomas Sailer |
| t.sailer@alumni.ethz.ch |