IDTV936 audio problems

We'd be happy to assist you with you questions.

Do you have an o-scope? Please capture the waveform and make sure it is what you had in mind.

Hi Paul thank you for your interest.

Unfortunately I've many open questions on my linux driver for IDTV936. I can try to expose to you one of my problems :-)

The main problem is that sometimes during a reprogramming sequence the audio disappear.

This because after reset sometime I need to reprogram registers of IDTV936 because I change the video format in the video capture control (reg 0x04 bit [2..0]),  for example from Input format 2 to Input format 0.

More or less the programming sequence is:
- POWER_CTRL, 0x01 put device in power saving mode
- wait if device is busy (test register 0x7C bit 0x40)
- write registers
- put device in full powermode (POWER_CTRL, 0x02)
- wait untill device it's busy (DEVICE_STATE == 0x10)
- trig configuration (register 0x03)

I repeat many times this sequence, changing video clock and input format and sometimes the audio in the monitor disappear.

I sure that the audio in i2s interface it's ok. In my opinion IDTV936 sometime stop to send audio in HDMI frame.

The only way to have audio again it's to reset IDTV936.

Do you have any suggestions?

Fabrizio,

Unfortuantely we are not able to comment on devices from other manufactuer. The only HDMI TX device that I have worked on is from Silicon Image, and I don't recall seeing anything wrong with that. What I will do is, again, capture video and audio at the TI device pin, and see if it behaves funny during reset and other activities. If TI device is good, I suggest you talk to IDT directly.

OK Paul

Thank you again, I'll try to write an email to IDTV support.

On my board I have an hdmi receiver (IDTV923) but I'm not sure that it's work so good to test my HDMI output :-)

BYE