I just connected a lcd 16x2 display to the raspberry pi (directly, no breadboard). I can display text and send command to it without problem. The only problem is that the text is black while it should be white (blue backlight). Any thought on how I could fix that? Thanks in advance!
closed as unclear what you're asking by Steve Robillard, Milliways, Dmitry Grigoryev, Darth Vader♦ Oct 12 '18 at 11:10
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Those HD44780 driven LCDs don't have reverse characters in their character set. If yours is displaying black text on the background, you are stuck with that.
— Well, you could undo the display frame and flip the polarizer, but most times, it's glued onto the glass. It's up to you if you find it worth a try. —
You end up with blue text on black then, of course. Cool? Not cool?
The "white text on blue" variant has a special blueish polarizer instead of a black one and a white backlight.
I just added a resistor and plug it to the 5V pin. Now it displays white on blue, as expected.