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flotulopex
- 1st October 2006, 20:26
Hello,

I'm using a HD44780 compatible LCD display.

I can't find any example about how to modify the existing character set.

Does anyone have a simple example how to do this?

Thank you

SteveB
- 1st October 2006, 20:53
In most HD44780 compatible LCD displays, you can only create 8 user-defined characters. They normally are the first eight character addresses (00h-07h). It's been a while since I have played with this, so if I can dig up an example, I'll post it.


Found something to get you started, but not an "example":
Have a look at Everday Practical Electronics (http://www.epemag.wimborne.co.uk/resources.htm) articles on "How to use Intelligent LCDs". The first article (http://www.epemag.wimborne.co.uk/lcd1.pdf), in experiment 6, explains how to use the 8 custom characters.

Will post more if I find it.

HTH,
Steve

sayzer
- 1st October 2006, 21:48
Hi flotulopex,

How did you miss this post?

Custom Character Generator
http://www.picbasic.co.uk/forum/showthread.php?t=2598

Don't forget to send your special thanks to Darrel Taylor!
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flotulopex
- 2nd October 2006, 10:33
Well,

Thank you (again) Darrel.



...I don't understand why I couldn't find this thread in my search...

sayzer
- 2nd October 2006, 10:43
If you are familiar with using Read/Write feature of LCD, then may be you could store your set in the LCD memory. But, I do not have experince on doing it.


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Darrel Taylor
- 2nd October 2006, 18:52
Hi flotul,

Hope it does what you need.

The normal character set is stored in ROM on the HD44780, so there's no way to change those. You're limited to just the 8 chars of CGRAM.

If you really need a whole different charset, then a Graphic LCD (GLCD) is the only way to go. But man those things are expensive. Not to mention it'll suck up a lot of program space in the PIC.

And, there's still stuff on the forum I've never even seen before. I sit in the "Who's On-Line" page alot and watch the search bot's roaming around. Almost everytime I'll see something that looks interesting that I've never noticed before. Having been here since the very beginning, it's amazing.

When you're looking for things in the forum, sometimes it's better to use the google "Site" search. Just enter site:picbasic.co.uk and then the keywords.

site:picbasic.co.uk lcd character (http://www.google.com/search?hl=en&q=site%3Apicbasic.co.uk+lcd+character&btnG=Google+Search)

It also allows 3 letter words, wereas searching for "LCD" with the forums search, won't work.
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SteveB
- 2nd October 2006, 19:13
When you're looking for things in the forum, sometimes it's better to use the google "Site" search. Just enter site:picbasic.co.uk and then the keywords.

site:picbasic.co.uk lcd character (http://www.google.com/search?hl=en&q=site%3Apicbasic.co.uk+lcd+character&btnG=Google+Search)

It also allows 3 letter words, wereas searching for "LCD" with the forums search, won't work.
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Darrel,
This info is well worth a sticky post in the FAQ section!

Steve

Darrel Taylor
- 2nd October 2006, 19:44
Probably a good idea. And I think I can do even better than that.

I'll see what I can come up with.

Thanks Steve,

flotulopex
- 2nd October 2006, 21:52
Thank you for your advise.

Next time, I'll find it by myself, for sure ;-)

woodygjw
- 2nd October 2006, 23:39
Hello flotul
You could also try searching these forums by typing something like lcd* character, or lcd*, or whatever you are looking for and that will turn out some results for you, always worked for me when the word was 3 letters or shorter.

Greg

Darrel Taylor
- 2nd October 2006, 23:48
A better Search tool for the Forum
http://www.picbasic.co.uk/forum/showthread.php?t=4751
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