Error connecting same source AVB on endpoint out

[charquet426]

Hello Everybody,

I designed an AVB endpoint card 8xIN 8xOUT, 1GHz Network with a XE216-512 configured with streams of one channel 48kHz.
The library used TSN 7.0.2.
All except one thing working properly
If I connect the same source of an IN's endpoint on multiple channels OUT of another endpoint,audio channels previously switched disappears.
For example I connect a stream of endpoint '0' source IN '0' to endpoint '1' destination OUT '0' -> OK, audio out. After then I connect another stream of the same source (endpoint '0' source IN '0') to endpoint '1' (same destination endpoint) destination OUT '1', the connection is good and the audio is well on channel 1 but disappears on channel 0.
Two streams do exist on AVB layer.

Does anyone has this problem ?

[Thomas]

You can get debug information from the realtime stack trace.
To enable the realtime stack trace over xSCOPE, follow the steps in APPENDIX B of application notes AN00202 or AN00203.

When you connect the second stream, additional messages will be printed.
Analysing those should provide additional clues.

[charquet426]

I traced the file debug the case described in the post. I made a mistake when connecting the problem seen in the AVB layer are false.
If someone has an idea !!

[ers35]

It looks like you are trying to connect the same talker source to multiple listener sinks. lib_tsn 7.0.2 does not support this. Each channel in a talker source stream has a one to one mapping to an output audio FIFO on a single listener sink. This is why audio disappears on one of the listener sinks when you connect the same talker source. See avb_1722_listener_process_packet() in lib_tsn/src/1722/avb_1722_listener_support_audio.c.

What are you trying to accomplish by doing this? There may be a workaround. Or, you could try adding support for one to many mappings to lib_tsn.

[charquet426]

The aim of my application is to distribute audio sources in several building. For example, each building have a endpoint and is divided into 8 zones.
So we can distributed in all areas of all building background music, therefore one source to all outputs (broadcasting). Specifically by area it is possible to transmit dedicated message at any time.
When I started this project one and half year ago, I did the first tests with the demo board XK-AVB-LC-SYS and the AVB library AVnu. With this system connect a single source to multiple outputs of the same endpoint worked.
I changed to a XK-AUDIO-216-MC model to use a network Gb but I must used TSN library.

[ers35]

Can you reproduce this test with the XK-AVB-LC-SYS? Were you using version 6.1.1 of the AVB endpoint software?

A potential solution is to connect the talker source only once and handle the copying of the samples to multiple (i2s, TDM, etc.) outputs in your application code.

[charquet426]

Yes I used the 6.1.1 library but I can not reproduce this test because I do not have the demos boards.

I thought to duplicate sources in the endpoint but I have to send a command SET_CONTROL from the controller to the concerned endpoint to indicate the source and destination of the duplication. I use AVDECC_LIB library for the controller and this feature is not implemented.

[ers35]

I checked 6.1.1 and the code is nearly the same. I tried the same test as you in the past with two XK-AVB-LC-SYS boards and I got the same result. Reading the code I do not see how this could have worked for you in the past.

[charquet426]

It is always possible that I made a mistake but I found in my notes this test and found a email to XMOS (without answer) with a question about this topic.
So I could have the same source to multiple outputs. If somebody can check it ?