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Author Topic: 128x64 GLCD ... scrolling data available?  (Read 1219 times)
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Tennessee
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I'm running a ks0108 (Satistronics) 128x64 GLCD.  With the system font used in the GLCD library, I can fit 7 rows of data on the screen.  If I need to display 8 lines or more, how can I set it up to scroll up and down to see all the data?

I assume I will have to install some buttons (scroll up, scroll down).  Im not sure if I'm even asking this correctly.  forgive my noobness.
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Dallas, TX USA
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Each character of the system 5x7 font is 7 pixels tall with 1 pixel of inter row pad below it,
which allows 8 rows of text to fit on a 128x64 pixel display.

Unfortunately the library does not buffer any character data, it renders characters
directly to glcd memory and does scrolling by moving the contents of that glcd memory around.
Since the library does not track/buffer any characters itself, once something is scrolled off the display,
it is essentially lost.

You might be able to implementing something on top of the library in your sketch to provide some sort
of virtual scrolling that works kind of like scroll bars in typical GUI text areas.

You would have to buffer all the lines of text and them print them line by line
as needed.
You might be able to take advantage of the text area scroll direction to perform
some scrolling in the glcd text area to keep from having to send entire screen of lines.

--- bill



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Tennessee
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I was afraid of that...  Doing "virtual buffering" in my sketch would be WAY more work than I wanted. 

Are the text-only LCD's the same? I definitely don't mind scooping a different LCD if that would work.
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I was afraid of that...  Doing "virtual buffering" in my sketch would be WAY more work than I wanted. 

Are the text-only LCD's the same? I definitely don't mind scooping a different LCD if that would work.
Pretty much. The scrolling will lose all contents after everything is scrolled out the memory or display area.

I'm working on some code to enable scroll arbitrary direction. Tune in if you're interested.

http://arduino.cc/forum/index.php/topic,60830.0.html
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Tennessee
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I was afraid of that...  Doing "virtual buffering" in my sketch would be WAY more work than I wanted. 

Are the text-only LCD's the same? I definitely don't mind scooping a different LCD if that would work.
Pretty much. The scrolling will lose all contents after everything is scrolled out the memory or display area.

I'm working on some code to enable scroll arbitrary direction. Tune in if you're interested.

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

Subscribed.  Thanks!
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