[LAD] Call for testing: new ALSA driver for Digi 002/003 family

Takashi Sakamoto o-takashi at sakamocchi.jp
Thu Apr 2 01:15:35 UTC 2015


Hi Damien,

On Apr 02 2015 09:28, Damien Zammit wrote:
> On 02/04/15 09:41, Takashi Sakamoto wrote:
>> Several issues are still remained:
>>   * When allocates 2 or more channel numbers for the device, after 15 to
>> 20 seconds from playbacking, any PCM samples causes noisy sound. Then,
>> all of LED on the front panel light. The streaming still continues
>> correctly.
> I have not seen this behaviour with your latest driver, Takashi.
> I think you would see this if the midi quadlet is confused with the pcm
> quadlets and you feed audio data into the midi port. (I have seen this
> before)

The channel is *not* PCM or MIDI, it's IEEE 1394 isochronous resource 
channels. I shouhd have mention about it, sorry.

In short, when two or more devices are connected on the same IEEE 1394 
bus, the driver may cause the issue (or not).

>>   * The actual effects of external clock source is not clear. When set
>> the clock source is somewhat external, even if stopping the clock
>> source, the device continues to sound PCM samples against my expectation.
>
> I have successfully tested the device with ADAT and SPDIF sync. When I
> connect external clock source to the SPDIF-in port and send
> 0xffffe0000118 1 the SPDIF led light turns on and the streaming now
> syncs to the new clock.  A flashing Sync led means that the sample rates
> are mismatched and the sync is not working correctly.  But sync works
> well when sample rates are matched.

OK. My Digi 002 Rack has no LEDs to show current clock source, so I have 
no way to check the actual sync in my eyes.

I request you to test stopping the supply of clock source during 
streaming. I expect the streaming is stopped suddenly, then PCM 
playback/capturing also stop.

> I tried 0x011c but I am not convinced that this is related to ADAT at
> all.  I think it is a switch to select the mode of SPDIF between
> consumer and pro SPDIF modes?  I am guessing here but SPDIF sync no
> longer works when I toggle the mode to 1, and it has no effect when I
> attach ADAT cable and sync to ADAT, then toggling the mode does nothing.

In my Digi 002 Rack, it's a selector between S/PDIF or ADAT for optical 
input/output interfaces. If not in your Digi 003+, this seems to be 
model-dependent issue and I'll drop it from the driver (digi00x-proc.c).


Regards

Takashi Sakamoto


More information about the Linux-audio-dev mailing list