DS90UB949-Q1: HDMI Audio device missing in device manager

Danny Feland1

Part Number: DS90UB949-Q1

Hi, I am looking for minimum requirements to enable built in HDMI Audio. The EVM kit displays an HD Audio device in the Windows Device Manager, but our custom board only shows a PNP Monitor and no Audio device. Is the EDID on the EVM kit and all die Revs identical to the datasheet example in "7.3.4.4 Internal Pre-Programmed EDID"?

over 3 years ago

0 Casey McCrea over 3 years ago

TI__Guru** 103215 points

Hello Danny,

Yes the EDID is the same. You can override the internal SRAM EDID using registers 0x48-0x4E

In your custom board do you have a deserializer connected/detected? There needs to be a deserializer present for the 949 to bring HPD high

Best Regards,

Casey

0 Danny Feland1 over 3 years ago in reply to Casey McCrea

Prodigy 20 points

Hi Casey,

Yes, I have a DS90UB948 connected. I verified HPD goes high, I've verified a data exchange occurs via DDC with Windows, and I have good video output on my target screen connected to the 948. I can also find a monitor device property in windows device manager that contains TXN0949, so I assume the DDC content is at least partially exchanging.

0 Casey McCrea over 3 years ago in reply to Danny Feland1

TI__Guru** 103215 points

Hello Danny,

Ok, the 949 SRAM defaults to 2 channel audio. Is this what you are trying to do?

Best Regards,

Casey

0 Danny Feland1 over 3 years ago in reply to Casey McCrea

Prodigy 20 points

Yes, I'm only trying to send I2S_DA to a 2 channel stereo amplifier IC.

0 Casey McCrea over 3 years ago in reply to Danny Feland1

TI__Guru** 103215 points

Hello Danny,

Ok, I'm not sure what you are saying the issue is exactly? You don't see the 949 device as an output device in the Windows Sound Settings? But you are seeing it a display device? Can you share some pictures of what you are seeing exactly?

Best Regards,

Casey

0 Casey McCrea over 3 years ago in reply to Casey McCrea

TI__Guru** 103215 points

Make sure AUX_I2S is strapped to "0" from the MODE_SEL0 pin

Best Regards,

Casey

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DS90UB949-Q1: HDMI Audio device missing in device manager