LCD Display (2x40, standard 14 pin LCD interface)
This is the basic wiring diagram for a standard HD44780 compatible LCD module.
/--------- LCD Module Connection ---------\
1 2 3 4 5 6 7 8 9 10 11 12 13 14 LCD pin numbers
o o o o o o o o o o o o o o
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- + C RS RW E D0 D1 D2 D3 D4 D5 D6 D7 LCD Pin names
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: : : : : : : : : : : : : :
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| | | B4 B5 B6 A0 A1 A2 A3 A4 A5 A6 A7 6522 IO Port names
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| | | o o o o o o o o o o o
| | | 14 15 16 2 3 4 5 6 7 8 9 6522 pin numbers
| | | \------- 6522 Connections ------/
| | |
| | \---| Contrast
| | v
| o---\VVVVV/-\ 10K Ohm variable resistor
| | |
| o +5vdc |
| |
o--------------/
_|_
-
gnd
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LCD_Byte - Print contents of A as a 2 character HEX number
LCD_Chr - Print contents of A as an ASCII chracter
LCD_Curs - Set the Cursor Position from A (0-4F)
LCD_Home - Move cursor to the home position without clearing display
LCD_Init - Initialize the display
LCD_Wait - Reads LCD command register and waits for it to be idle, returns
with the address pointer (cursor position) in the A register.
LCD_Write - Strobes the Enable Pin and waits for the LCD to process the command.
Uses LCD_Wait so cursor position is returned in A register.
You can download the source code under the Downloads tab.