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I have an LCD from a Chonese manufacturer. 12.3", resolution is 1920x720 pixels. When I set the following in the config.txt file I get some white stuff at the bottom of the screen. Any ideas why?

This is my config.txt file contents:

hdmi_force_hotplug=1
hdmi_group=2 
hdmi_mode=1 
hdmi_mode=87 
hdmi_cvt 1920 720 60 6 0 0 0

Here is the image of what the output looks like: Here is the image of what the output looks like:

The manufacturer also has provided the following advising to set the HDMI to, but I'm unsure of how to set this up in the config.txt file.

#define   Vclk_MHZ   132
#define   LCD_XSIZE   1920
#define   LCD_YSIZE   720
#define ADJHIGHT    LCD_YSIZE

#define   LCD_BPP      16

#define FRAME_RATE   60

#define   LCD_ROTATE   0


#define  HBPD       110
#define  HFPD        8
#define  HSPW       8

#define  VBPD        10
#define  VFPD        10
#define  VSPW        4

Any help is appreciated. Thank you.

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I'm pretty sure we have the same screen (CDTech 12.3 inch 1920x720)

I had the same issue when I typed following into the config.txt file:

hdmi_cvt=1920 720 60 0 0 0 0

However, it turns out the pi doesn't properly adjust the pixel frequency of the display. You might need to do some tuning, but the process should more or less be the same. In your config.txt file, add this line above the "hdmi_group" property:

hdmi_ignore_edid=0xa5000080

This will disable the pi from automatically assuming an approximate pixel frequency, which is likely causing our issue. Next, toward the end of the config.txt file, add this line:

hdmi_timings=1920 0 88 44 148 720 0 4 5 36 0 0 0 60 0 109244953 1

I've obtained these values by running an EDID scan (not entirely sure what that even means lol) and using this webpage, which is a great resource: https://www.raspberrypi.org/forums/viewtopic.php?t=24679

The second to last number might be specific to your module (I think), but it doesn't hurt to try the number I posted. This is the pixel frequency.

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