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Author Topic: Scroll LCD bottom line  (Read 1649 times)
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Need to scroll only bottom line of standard H44780 4 bit mode 16 x 2 LCD. Top line to stay fixed. I've been all over this forum, many confusing answers. Does an appended LiquidCrystal library exist to do this function? I would like to reopen this subject for more ideas or a solution.
Thanks
 
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The HD44780 LCD controller cannot inherently shift one line without the other and I don't know of any libraries that do this in software.  The best way to accomplish this is to shift both lines and then rewrite the line(s) that you didn't want to change.  If you haven't noticed, the correct terminology is shift not scroll.  That's how it is described in the LCD controller data sheet.

Don
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From my reading, it sure seems true what you said.  I thought by now a library might have developed. Thanks for a concise 1 sentence idea of a shift procedure.

Also Don
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Quote
From my reading, it sure seems true what you said.
Would I lie to you?

Quote
I thought by now a library might have developed.
That's not as easy as it may seem due to the wide variety of displays that are run from the same (ancient) controller.  For some insight into the problem check out the LCD Addressing link at http://web.alfredstate.edu/weimandn.

Don
« Last Edit: May 17, 2011, 08:36:28 pm by floresta » Logged

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Check this out. I've not published my codes yet, still a few more things to add before I roll out the new library version:

http://arduino.cc/forum/index.php/topic,60830.0.html

You can scroll back and forth with text area and scrolling list items.
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