[HDMI2USB] HDMI Audio to USB Sound

[mithro]

More technical details at

• HDMI2USB-misoc-firmware #160
• HDMI2USB-jahanzeb-firmware #15

Brief explanation

Push audio from HDMI to USB sound in the HDMI2USB project.

Expected results

HDMI audio is captured on a computer connected to the HDMI2USB device.

Detailed Explanation

HDMI supports sending audio over the interface (in the blanking areas called data island). This audio should be captured and sent up the USB interface.

Further Reading

• HDMI2USB Website
• Migen / MiSoC
• HDMI2USB-misoc-firmware
• USB Audio specification
• HDMI Data Islands
• HDMI Audio

Contacts

• Potential Mentors: @shenki @mithro @enjoy-digital
• Mailing list: [email protected]

[lucribas]

Hi.
I have interest in collaborate.
Are you considering only code written in Migen/python or VHDL can be accept?

[Silipwn]

I would like to work on this issue, but I am relatively new to VHDL and Migen. Any tips to follow?

[mithro]

We already have someone who is about to work on the USB side of things, so I would recommend concentrating on the HDMI side.

Firstly, I would start by watching my Dissecting HDMI (33c3). Then I would recommend taking a look at some of Hamster's stuff at http://hamsterworks.co.nz/mediawiki/index.php/Minimal_HDMI

Once you are happy with the ideas / concepts there. Then I would recommend taking a look at my stuff at TMDS repository and Google Doc with more info.

Work on extending the TMDS repository to support the data island encoding / decoding. Once the data island stuff works, then you can look at doing audio using that...

[Silipwn]

I would be working on the same, but please excuse me for my delay, I am just getting started with HDL and Migen & MiSoC are new concepts, so taking some time before I can really contribute something.

[mithro]

As mentioned, doing small extensions / improvements to my TMDS repository is a great way to get started!

[akhil-123]

A proposal for this particular problem was written for GSoC 2014. How much work is left?

[mithro]

@paddatrapper - Can you give an update on the status here?

[paddatrapper]

@akhil-123, I did some work on the USB audio side of things during last year's GSOC, the result of which can be seen in PR HDMI2USB-fx2-firmware/#43 and various commits to master. The USB headers are implemented and the FX2 chip can act as either a recording or an output device. I am working (read getting stuck) on getting two FX2 dev boards to work as a loopback device. Currently the issue is that the FX2 buffers are not filling/emptying correctly and so communication between the two devices fails.

There has been no work on adding audio capture to the FPGA yet.

[Arna-Maity]

Hi, i am to new to this project and would like to know present state of the project? How much is already done and how much is left?

[paddatrapper]

@Arna-Maity - nothing has really changed. The PR and commits to HDMI2USB-fx2-firmware master in 2017 are the current state of this issue