Testing displays for bad pixels

[tago]

Hi,

i wonder how to test new displays for bad pixels.

I have some standard 128x64 OLEDs and some character LCDs i'd like to test.

My first idea was to enable/disable all pixels at once. Is this sufficient? If yes, which char displays all available pixels per char?

 

Thank you!

Edited March 29, 2019 by tago

[tago]

According to the HD44780 datasheet i need to send 1111/1111 to the display to enable all pixels per char, but don't know the string equivalent is to enter in the .ngc file.