NHD-3.5-640480EF-MSXP-CTP connection with Raspberry pi 4 using MIPI DSI interface

Hello, 

I'm currently trying to use the TFT display NHD-3.5-640480EF-MSXP-CTP with my raspberry pi 4 : I can see the backlight is working, but I get no images (black screen). 

I read the product specification document but I'm a bit confused, so I wanted to check with you if I understood correctly. Here is my wiring drawing : 

Since the pi has only two DSI lanes, I connected the DSI lanes 0 and 1 to the corresponding pi lanes, and the DSI lanes 2 and 3 to the ground (as stated in the documentation : Connect DSI_D3P/N and DSI_D2P/N to VSS in 2 data lanes application.) . 

I connected the T_IM signal to VSS in order to select the interface to MIPI DSI. 

I connected the RESX to VDD since it's active low. 

Finally, I set the IM1, IM0 and LANSEL respectively to 1 0 0, in order to keep the default data lanes. 

Can you confirm that my wiring is ok ? 

When I tried to connect it to the pi, it did not work. So I did some research online and on this forum, and I found out that there might be a power on sequence, where I should use the SETMIPI command in order to inform the screen that I want to use 2 lanes. But I want to use the MIPI DSI interface, not the DPI/DBI type-C Option 1 

So my question is : Should I set T_IM to 1 at startup, in order to send the command SETMIPI to set the number of lanes to 2, and then switch T_IM to 0 in order to select the interface to MIPI DSI ? 

Best regards ,

Flogo

PS: On the raspberry pi, I installed the raspbian image 64 bits based on Bookworm. It's working with another screen on the MIPI DSI port.