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I am working on my first LCD project. Its a 4 X 16 44780 controlled LCD.
In the PBP manual for LCDOUT, two schematics are presented. One uses four data lines, the other eight. What I don't understand is why I would use eight when it appears I can use four.
BTW, I am using a 16F886, if that makes any difference.
Would someone be so kind as to explain this to me? I have searched the forum, but can't seem to find anything on this, and the PBP manual doesn't explain why either.
Thanks,
Andy
Sorry, I meant 4 X 20 characterQuote:
Originally Posted by andywpg
I'm curious also. The closest I could google for an explanation was:
http://www.cornerstonerobotics.org/c...rii14_lcd1.pdf
I'm guessing there was an evolution of hardware involved. The parallel LCDs were most likely first used by devices that used 8 bits (1 byte) - I'm going to guess discrete components. Then microcontrollers came along and were smart enough to be able to use only 4 lines.Quote:
p. 2
This 4-bit mode is beneficial when using a
microcontroller, as fewer input/output lines are required.
From everything I've seen so far, it's a personal choice. I used 8 before, but I'm now starting to use 4 because my projects become more complex and pin usage becomes more important.
Robert
:)
It's just faster, but in 99.999% of the application you don't need it that fast.
Theoreticaly it should be twice as fast, since with the 8 lines you send one byte while with 4 lines you have to send two nibbles.
Al.