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Rarely right after the startup my LCD display shows half the screen completely white, the other half shows the software without problems. The main problem here is that to see this problem I have to initialize my hardware a lot of times, I don't have the exactly figures but maybe once every one hundred initializations. Once the display is initialized with the problem the software and the touchscreen work as expected. But I see a pattern that maybe can help me to understand what goes on when the problem happens.

The screen is always divided in half vertically with one half working and other in white. If this is a random bug, the screen would be white on diferent proportions horizontally or vertically; The half section that does not show the software is always white. After a couple of tests I've noticed that the white color is the color when nothing is written on the pixel; The bug is very rare. And even at this low probability, when this happens the problem is the same, half the screen on white color;

I am using a LPC1788 connected to a LVDS transmitter (DS90C383B) and then to my LCD (HDA700L-GHL - 7”, WVGA 800 X480 , TFT Color Graphics ,White LED Backlight).

Can someone give me some advice? Thanks

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  • \$\begingroup\$ Look for a race condition in your initialization code \$\endgroup\$ – DoxyLover May 26 '17 at 1:00
  • \$\begingroup\$ Power OK before Reset ? \$\endgroup\$ – Sunnyskyguy EE75 May 26 '17 at 4:27
  • \$\begingroup\$ I am willing to think that the problem has some relathionship with the signas HSYNC and VSYNC. But I still do not know how these signals can make only half the screen be drawn on the LCD. \$\endgroup\$ – Rodolfo May 26 '17 at 13:57
  • \$\begingroup\$ I don't think that the code is the one to blame, but who knows. About the power, once I saw the problem with my equipment loosely attached to the power cable. \$\endgroup\$ – Rodolfo May 26 '17 at 14:19

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