Loopback with AVB AUDIO ENDPOINT

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vinaykmurthy
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Loopback with AVB AUDIO ENDPOINT

Post by vinaykmurthy »

Hello All,

I have got 2 AVB Audio End Point Reference boards and I am trying to get a loop-back of audio working with it. 

I have connected the output from iPod to the "Audio Input Jack" on one device. The 2 devices are connected via RJ-45 cables. For the other device, I have connected it to the speakers. I am now streaming audio to see if the data can be received on the other side. However, I see that there is no audio on the receiver side.

I searched thro' various videos given in the xmos site, but none of them show a configuration with just 2 devices.

1) Can you please let me know if this is a valid configuration.

2) If so, can you please help me point out what is needed to get the above set-up working.

Thanks,

Vinay

 



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Andy
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Post by Andy »

Hi Vinay,What version of the firmware are you running?
vinaykmurthy
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Joined: Mon Nov 10, 2014 6:40 am

Post by vinaykmurthy »

Hello Andy,

 

I have downloaded the 6.0.4 source code (AVB-Endpoint-Software(6.0.4).zip) from the web and compiled it.

 

-Vinay

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larry
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Post by larry »

The AVB Endpoint Quick Start Guide is worth double checking step by step if you haven't done that yet.

vinaykmurthy
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Post by vinaykmurthy »

Hello Larry,

Thanks for the reply.

I have followed the Quick Start Guide and I have also referred the page https://github.com/xcore/sw_avb/blob/ma ... kstart.rst

The web page says that "Connect the two development boards together directly via an Ethernet cable between the RJ45 connectors", but the Quick Start Guide mentions that "Connect the two development boards into an AVB capable Ethernet switch via the provided Ethernet cables".

I have tried both but without any luck. When I probe the clock on both the xmos devices, I see that there is a drift between them. The first one shows 20.831us where-as the other one shows 20.835us. They appear not be in sync. Is this a normal behavior ? 

Really appreciate any help on this.

-Vinay

vinaykmurthy
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Post by vinaykmurthy »

Hello All,

An update on my experiment. I have connected the 2 xmos devices via an AVB enabled switch so that I can snoop all the packets. 

I am observing that both the xmos devices are not sending any "ANNOUNCE" messages. I only see MSRP and PATH delay messages. With this, both the xmos devices are assuming that they are grand-masters and hence the clocks are not in sync. 

Can you please let me know is there any quick diagnostic test to confirm if the xmos devices that I have is faulty or not ?

-Vinay

trice001
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Post by trice001 »

thanks
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