Connecting LCD to PIC32 PWM Channel

[MarkoSan]

Dear Sirs and Madams!

I am little confused regarding connecting negative (RGB Characters on Black Background) RGB 1602 LCD Display (HD44780 Controller) to PIC32's PWM Channel. Here is a pin listing:
Now, I've already connected normal 1602 LCD Screens on PIC32 and they work fine. I just need some help connecting Contrast via PIC32's PWM module and how do I connect those three Cathodes, so I will be able to change text color at runtime from software?

Sincerely,
Marko

 

[Ian Rogers]

Now, I've already connected normal 1602 LCD Screens on PIC32 and they work fine. I just need some help connecting Contrast via PIC32's PWM module and how do I connect those three Cathodes, so I will be able to change text color at runtime from software?

The RGB connections are just backlights... It won't change the colour of the text... However, the appearance may look like a change of colour...

Just connect a transistor to each of the pins.. Connect the base of the transistor via a suitable resistor to the pin of the micro... Also connect the collector via the recomended resistor to the RGB connections on the display... The emitter to ground.

As for the contrast... I have never connected that through PWM.... I'm not even sure its the best way to go... I would personally use a digital pot for that...

 

[MarkoSan]

The RGB connections are just backlights... It won't change the colour of the text... However, the appearance may look like a change of colour...

Just connect a transistor to each of the pins.. Connect the base of the transistor via a suitable resistor to the pin of the micro... Also connect the collector via the recomended resistor to the RGB connections on the display... The emitter to ground.

As for the contrast... I have never connected that through PWM.... I'm not even sure its the best way to go... I would personally use a digital pot for that...

Well, I have this LCD, take a look at the video:

As you can see, the LCD is negative (black background - backlight) and text color is changing. What I want to control is, RGB text color with PWM.