[alsa-devel] Behringer FCA 202 packet dump (Re: [PATCH 1/4] ALSA: firewire-lib: add buffer-over-run protection at receiving more data blocks than expected)

Takashi Sakamoto o-takashi at sakamocchi.jp
Sat May 16 13:30:01 CEST 2015


On May 16 2015 20:22, Takashi Sakamoto wrote:
> But, Behringer F-Control Audio 202 (based on OXFW 970) has a quirk to
> postpone transferring isochronous packet till finish handling any
> asynchronous packets. In this case, this model is lazy, transfers no
> packets during several cycle-start packets. After finishing, this model
> pushes required data in next isochronous packet. As a result, the
> packet include more data blocks than IEC 61883-6 defines.

This is an actual packet dump. We can see this model postpone
transferring packets during handling asynchronous transaction.

FYI

-- Time expressed in clock-ticks of 10.172526 nSec
19657542078 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F3F024 speed=100
19657546326 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  02020072 900002E4 40FFFF8B
40000005   [...r.... at ...@...]
                               0010:  40FFFFD8 40FFFFFD 40FFFF37
40FFFFA5   [@... at ...@..7 at ...]
                               0020:  40FFFE81 40FFFF2F
    [@... at ../]
19657554363 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F40024 speed=100
19657559477 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  02020076 90000351 40FFFF1C
40FFFF95   [...v...Q at ...@...]
                               0010:  40FFFF01 40FFFEF6 40FFFF2E
40FFFF77   [@... at ...@... at ..w]
                               0020:  40FFFEE9 40FFFF72
    [@... at ..r]
19657566647 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F41024 speed=100
19657570253 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  0202007A 90000244 40FFFF11
40FFFF80   [...z...D at ...@...]
                               0010:  40FFFF2A 40FFFFA7 40FFFF40
40FFFF71   [@..*@... at ..@@..q]
                               0020:  40FFFF0E 40FFFFB1
    [@... at ...]
19657578933 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F42024 speed=100
19657582987 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  0202007E 900002B4 40FFFF8C
40FFFFC5   [...~.... at ...@...]
                               0010:  40FFFF79 40FFFFBB 40FFFFDE
40FFFFE0   [@..y at ...@... at ...]
                               0020:  40FFFFF2 40000031
    [@... at ..1]
19657591217 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F43024 speed=100
19657595721 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  02020082 90000324 4000004C
4000004B   [.......$@..L at ..K]
                               0010:  40000054 40FFFFF9 4000004D
40FFFFFE   [@..T at ...@..M at ...]
                               0020:  40000053 4000003F
    [@..S at ..?]
19657600127 ReadReq        dst=0xFFC2 label=36 rcode=retry_X src=0xFFC3
offset=0xFFFFF0000904 speed=400 ack=ack_pending
19657603503 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F44024 speed=100
19657615788 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F45024 speed=100
19657628072 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F46024 speed=100
19657633918 ReadResp       dst=0xFFC3 label=36 rcode=retry_X src=0xFFC2
response=resp_complete data=0x81008042 speed=400 ack=ack_complete
19657640358 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F47024 speed=100
19657644228 Streaming      length=136 tag=1 channel=0 synchronization=0
speed=400
                               0000:  02020086 90000257 40FFFFE9
4000003C   [.......W at ...@..<]
                               0010:  40000000 40FFFFE2 40FFFFDF
40FFFFD9   [@... at ...@... at ...]
                               0020:  40000010 40000024 40FFFF6E
4000000B   [@... at ..$@..n at ...]
                               0030:  40FFFFC7 40FFFFE8 40FFFFE6
40FFFFAF   [@... at ...@... at ...]
                               0040:  40FFFFE1 4000002A 40000039
4000004A   [@... at ..*@..9 at ..J]
                               0050:  40000055 40000043 40000091
400000C0   [@..U at ..C@... at ...]
                               0060:  40000089 40000010 40FFFFEF
40FFFFE7   [@... at ...@... at ...]
                               0070:  40000036 4000001D 40FFFFF8
40FFFFD5   [@..6 at ...@... at ...]
                               0080:  4000001C 40000014
    [@... at ...]
19657652642 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F48024 speed=100
19657657066 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  02020096 900002F1 40FFFFC2
40FFFF9F   [........ at ...@...]
                               0010:  40FFFFC1 4000000A 4000002A
40000018   [@... at ...@..*@...]
                               0020:  40FFFFA5 40FFFFD5
    [@... at ...]
19657664928 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F49024 speed=100
19657670106 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  0202009A 90000380 40000044
40000053   [........ at ..D@..S]
                               0010:  40000050 40000046 40000086
4000003A   [@..P at ..F@... at ..:]
                               0020:  4000006D 4000002D
    [@..m at ..-]
19657677213 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F4A024 speed=100
19657680881 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  0202009E 90000253 4000006A
40000047   [.......S at ..j@..G]
                               0010:  40000056 4000000A 40000074
4000001F   [@..V at ...@..t at ...]
                               0020:  4000004A 4000004A
    [@..J at ..J]
19657689497 CycleStart     dst=0xFFFF label=0 rcode=retry_1 src=0xFFC3
offset=0xFFFFF0000200 cycle_time_data=0x58F4B024 speed=100
19657693615 Streaming      length=40 tag=1 channel=0 synchronization=0
speed=400
                               0000:  020200A2 900002C4 40000030
40000014   [........ at ..0@...]
                               0010:  4000002F 4000002D 40000013
4000001A   [@../@..- at ...@...]
                               0020:  4000002F 40FFFFBE
    [@../@...]


Regards

Takashi Sakamoto


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