I was once porting my OS to a new platform, and hadn't got the screen to work yet. What I did get to work was the screen's backlight, so I would have it blink t

I was once porting my OS to a new platform, and hadn't got the screen to work yet. What I did get to work was the screen's backlight, so I would have it blink to show debugging info. It was a huge pain in the ass.