HD 44780 module and LCD soldering

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21

@ Alex Bilityuk - That means that the contrast needs a potentiometer or maybe half the voltage on the pin. You will need a voltage divider of some type to reduce the contrast.

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22

@ Alex Bilityuk - You could maybe connect a PWM signal pin to that contrast pin to reduce the voltage that way.

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23

Or Analog Out if there is enough current.

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This won’t work actually, not that easy anyway. There are 2 resistor on your board that act like a voltage divider. You can also solder a pot instead.

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25

I experienced the same when using this board and ended up removing R1 and R2 and replacing them with something like a 10K and a 1K resistor respectively. The contrast and viewing and is now perfectly usable. This ended up giving a voltage on pin 3 of the LCD of something like 0.3V which worked well.

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26

Could you tell please how to use cerbuino bee output analog pin in code and set 0,3v as Jason adviced?

Ok i will try to find a 10k and 1k resistors, but this is a problem im our town… Maybe i will need some time to use internet shop.

Could you explaine please how to make a pot?

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@ Alex Bilityuk - Check this tutorial on how to use AnalogOut

https://www.ghielectronics.com/docs/10/analog-outputs

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Nice. it will be the first variant i am going to try, cuz i dont have a resistors yet…

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@ Alex Bilityuk - Check how much current the contrast pin on the display draws, just to be sure. Microcontroller pins don’t provide much, but it might be enough.

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Here we go guys! I want to thank all of you for advices and help! Finally i used break away headers and soldering, also i set the 3-rd pin to resistance regulator to set up a contrast manually!

Here is a picture (attached).

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@ Alex, congratulations. It seems like your persistence paid off. We’ll keep watching and see what other great things you create.

Well done.

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32

This is great, and a really good example of the helpfullness of this forum. Stay cool guys! :dance:

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33

Good job!

What are those white artifacts at the bottom of the display?

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34

Those appeared on the first image too. Interested to know what is causing them as they don’t seem to align with the pixels of the display.

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35

Reflections?

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36

More like dead pixels.

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37

It is dead pixels, but it’s not a problem…

You are right, that’s it…

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I can’t see how as part of the artifacts we are seeing are outwith the normal 5x7 pixel area.

This is a character display.

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I suppose you a right. Lets think this is mistic wite spots ))

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These pixels are liquid. When they die they leak all over. ;D

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