HDMI DDC (I2C) speed

When trying to work with HDMI, we found out that the speed of DDC (I2C) Jetson Nano is 400 kHz.
Our display only supports 100 kHz. Can the speed be reduced to 100 kHz?

HDMI requires that the E-DDC implement [I2C] standard mode speed (100 [kbit/s] and allows it to optionally implement fast mode speed (400 kbit/s).

So, I need standard speed.

Are you sure you have to use 100kHz?

Our HDMI DDC is already implemented and other user’s usecase is working fine with ddcutil too.

We have some device with HDMI DDS speed only 100 kbps, our display works fine.
With Jetson - no picture.

We examined any HDMI differences between Jetson and our device - found only a difference in DDC speed…

Our display is old (10 years), but we cant change it, because this is the customer’s display and he has a lot of them…

So we need to try change DDC speed, no more ideas…

There is no update from you for a period, assuming this is not an issue any more.
Hence we are closing this topic. If need further support, please open a new one.

Maybe you should share us the dmesg log to check first.

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