User manual

7) PYTHON SCRIPT for PI LCD, PART 4:

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# LCD4: Learning how to control an LCD module from Pi

# See w8bh.net for more information.

########################################################################

import time #for timing delays

import RPi.GPIO as GPIO

import random

#OUTPUTS: map GPIO to LCD lines

LCD_RS = 7 #GPIO7 = Pi pin 26

LCD_E = 8 #GPIO8 = Pi pin 24

LCD_D4 = 17 #GPIO17 = Pi pin 11

LCD_D5 = 18 #GPIO18 = Pi pin 12

LCD_D6 = 27 #GPIO21 = Pi pin 13

LCD_D7 = 22 #GPIO22 = Pi pin 15

OUTPUTS = [LCD_RS,LCD_E,LCD_D4,LCD_D5,LCD_D6,LCD_D7]

#HD44780 Controller Commands

CLEARDISPLAY = 0x01

RETURNHOME = 0x02

RIGHTTOLEFT = 0x04

LEFTTORIGHT = 0x06

DISPLAYOFF = 0x08

CURSOROFF = 0x0C

CURSORON = 0x0E

CURSORBLINK = 0x0F

CURSORLEFT = 0x10

CURSORRIGHT = 0x14

LOADSYMBOL = 0x40

SETCURSOR = 0x80

#Line Addresses.

LINE = [0x00,0x40,0x14,0x54] #for 20x4 display

battery = [

[ 0x0E, 0x1B, 0x11, 0x11, 0x11, 0x11, 0x11, 0x1F ], #0% (no charge)

[ 0x0E, 0x1B, 0x11, 0x11, 0x11, 0x11, 0x1F, 0x1F ], #17%

[ 0x0E, 0x1B, 0x11, 0x11, 0x11, 0x1F, 0x1F, 0x1F ], #34%

[ 0x0E, 0x1B, 0x11, 0x11, 0x1F, 0x1F, 0x1F, 0x1F ], #50% (half-full)

[ 0x0E, 0x1B, 0x11, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F ], #67%

[ 0x0E, 0x1B, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F ], #84%

[ 0x0E, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F ], #100% (full charge)

]

patterns = [

[ 0x15, 0x0A, 0x15, 0x0A, 0x15, 0x0A, 0x15, 0x0A ], #50%

[ 0x0A, 0x15, 0x0A, 0x15, 0x0A, 0x15, 0x0A, 0x15 ], #alt 50%

[ 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15 ], #3 vbars

[ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ],