MIPI-DSI VFP, VBP value settings

[burhanhagi]

I will implement driver code for a MIPI-DSI based LCD Display in my custom IMXrt1170 card.

Before doing that, I am trying to understand the examples in SDK with LCDIFv2 MIPI DSI based ones.

I could not understand one point that: As you see below SS,  VFP and VBP configuration values of Display in SDK example code is different from RK055MHD091 Panel datasheet. (Both values must be 2 each as per datsheet). How values code in BSP calculated ? Where I am missing? Thanks.

Datasheet says that for VFP and VSP setting, refer to application note. But it does not mention which application note? 

[burhanhagi]

Hi @Gavin_Jia , As you see the picture I added in my previous post; HS, HBP and HFP values in code was entered correctly . Those values match with the values in datasheet. They are also specified as min. values in datasheet.  See the below;

So again, it is important for me to understand how VFP and VBP values calculated? Thanks again

[Gavin_Jia · Accepted solution]

Hi @burhanhagi ,

Thank you for your patience. I have re-discussed this issue with internal experts and confirmed that theoretically the value only needs to be greater than the given minimum value. The configurations in the SDK are from the optimal results provided by vendor, you can refer to the configurations in the SDK or try to fine-tune them yourself. 

Hope this helps!

Best regards,
Gavin

[Gavin_Jia]

Hi @burhanhagi ,

Thanks for your interest in NXP MIMXRT series!

The vertical/horizontal front/back porch values are display dependent, their appropriate values should be found in the display data sheet document.

Looking at the code and the datasheet, what's in the code should be the typical value we need, although the datasheet doesn't give a typical value. I'm not sure why it's missing here and need to confirm this internally.

Best regards,
Gavin