HDSP release notes

From the ALSA wiki

Latest revision as of 20:11, 3 January 2007

I'm pleased to announce that ALSA now has support for the Hammerfall DSP audio interface. Details of the Hammerfall DSP are available at RME's website (www.rme-audio.com).

The driver supports:

• all sample rates
• both MIDI ports
• "simple mixer" controls to allow alsamixer to control each playback stream's volume. Remember: as usual with ALSA, the initial state is "all output muted".
• peak meters for input, output and playback, with serial clipping counters.
• a non-standard control element for the matrix mixer (this may change; do not plan long term application support around it)

Things that are not tested but should work:

• big-endian systems
• multiface i/o box
• cardbus interface
• different sample clock sync sources

Things that don't work:

• RMS meters
• Flashing the firmware into the I/O box

The driver is similar in some ways the Hammerfall driver. Most notably, it requires large chunks of physically contiguous memory. This is best provided for by loading the snd-hammerfall-mem module early during booting, which provides memory for both Hammerfall and Hammerfall DSP drivers. The module has a snd-enable option which takes a comma-separated list of 0's or 1's indicating whether or not to allocate memory for the n'th Hammerfall or Hammerfall DSP device. If you have only once such device, then snd-enable=1 will be sufficient. The module checks for installed devices, so you can always insert the module and the right thing will happen even if you have removed your Hammerfall/Hammerfall DSP cards.

I am sure there will be minor glitches along the way. I would really appreciate feedback from anyone with an H-DSP (marcus - that means you! :)

A huge thank you to RME for the foresight and sense to make available sufficient information to make this driver possible.