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Author Topic: 16x2 LCD - some text displaying, some not  (Read 929 times)
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Hey all, I'm using an Arduino Mega 2560 and a 16x2 LCD from sparkfun. I'm using buttons to scroll through a menu. There are 5 options on the first level. For 3 of the options it displays the text on the screen perfectly. I set the contrast with a 10k trimpot and it looks great. However, for 2 of the menu options the contrast is screwed up and it's too dark to see anything. As soon as I scroll back up things will display properly. This happens in some of the other levels of the menu as well. Anybody have any ideas for what's going on? At the very least I'd like to be able explain why this is happening.
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Don't know what type of menu library you are talking about or even what code you are using. If I lived in your head, I'd ask your brain for all the above.  smiley-wink
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Current consumption? More details?
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Don't know what type of menu library you are talking about or even what code you are using. If I lived in your head, I'd ask your brain for all the above.  smiley-wink

Good point, my apologies. I'm using the LiquidCrystal Library with the Arduino so the code is rather simple. The menu is a self-designed menu for a project. Basically I display something and I can hit either up or down and the LCD will display something else. For some text I need to display the contrast is set perfectly, but when it displays other text the screen goes dark and I can hardly see what's being displayed.
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Well it seems to me that your connections to pin whatever are wrong and line something in your sketch is messed up as well.  I suppose when my crystal ball gets back from the shop I can give you a more specific answer.

Don
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Well it seems to me that your connections to pin whatever are wrong and line something in your sketch is messed up as well.  I suppose when my crystal ball gets back from the shop I can give you a more specific answer.

Don

What else do you need to know?
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... the code is rather simple ...

Show the code? Perhaps a photo or description of the wiring. Are you using a battery / power pack / USB?
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What else do you need to know?

Basically everything. 

You have some hardware, the LCD display and the Arduino, that are somehow interconnected.  I have to know how you intended to connect them (a circuit diagram) and how you actually connected them (a photograph).

You have some software running on the Arduino.  This consists of some pre-written (library) code and some that you wrote yourself.  I need to see the code along with a description of how it is supposed to function and how each portion of your code works toward that end.

The ultimate output is designed to be displayed on a LCD.  I have to know what is supposed to be displayed under some specific circumstances along with what is erroneously displayed.

I'm sure there is more, but that's what comes to mind so far.


Don
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