[FFADO-devel] AMDTP data from Fireworks

[Takashi S. <o-t...@sa...>]

Dear developers,

I'm a newbile for this project and the guy who is working for fireworks
driver in kernel land utilizing ALSA framework as Doug MxLain menthioned.
http://sourceforge.net/mailarchive/message.php?msg_id=30581442

The aim for this mail is to ask you the AMDTP data from Fireworks. For
me, it looks not to be IEC 61883-6 conformable.

Today I receive common isochronous packets from my target device.

For example (Each datum are shown as 32 bit little endian):
0x3F110018
0x9000897B
0x000004C6
0x00FFFFF8
0x00000060
0x00000040
0x00000024
0x00000028
0x00000021
0x00000034
0x00000000
0x00000000
0x00000000
0x00000000
0x00000000
0x00000000
0x00000000
0x00000000
0x80000000

The first two data are common isochronous packet headers.
It means its format is "Audio and Music" and event type is
"Basic format for AM824".

Here my target device transmit 16ch PCM samples and the
last datum is for MIDI (LABEL = 0x80).

But each Audio data has no labels. The label is always 0x00.
I think It should be 0x4X (X differs depending on sample width)
because its format is already shown as AM824 data in CIP header.

Is this IEC 61883-6 comformant or not?


========
My source is here.
https://github.com/takaswie/snd-firewire-improve

I success to transmit 16 channel PCM sample to my target device
(AudioFirePre8) in any sampling rates and implement several commands
such as retrieving hardware metering and so on. Ladish Clemens also
developed ALSA's fireworks driver but my driver utilizes
snd-firewire-lib.ko.

My aim is also expanding snd-firewire-lib.ko with receiving AMDTP
packets and handling MIDI. If Fireworks is not comformant to IEC
61883-6, I should implement it in my snd-fireworks.ko, not in
snd-firewire-lib.ko.

Regards


Takashi Sakamoto
o-t...@sa...