Mukhammad

try
 
sudo h3disp -m 5 -d  
and reboot
 
If you get a clear display, you can set the display area to 800x480 later by modifying the script.bin file.
 
[disp_init] disp_init_enable = 1 disp_mode = 0 screen0_output_type = 3 screen0_output_mode = 5 screen1_output_type = 3 screen1_output_mode = 5 fb0_format = 0 fb0_width = 800 fb0_height = 480 fb1_format = 0 fb1_width = 0 fb1_height = 0 hdcp_enable = 1