LCD DIsplay on GPIO ports

[mauris]

I try use a LCD display 16*2 with the GPIO ports of the A13, I have installed the GPIO_A13 library with this instructions https://github.com/OLIMEX/OLINUXINO/tree/master/SOFTWARE/A13/PYTHON-A13-GPIO
For this project I use a code make for the Rasberrypi and I think that I forget something to adapt the code for A13

http://mchobby.be/wiki/index.php?title=Rasp-Hack-Afficheur-LCD-Python

Python code (class) :

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#!/usr/bin/python

#
# based on code from lrvick and LiquidCrystal
# lrvic - https://github.com/lrvick/raspi-hd44780/blob/master/hd44780.py
# LiquidCrystal - https://github.com/arduino/Arduino/blob/master/libraries/LiquidCrystal/LiquidCrystal.cpp
#

from time import sleep

class Adafruit_CharLCD:

    # commands
    LCD_CLEARDISPLAY = 0x01
    LCD_RETURNHOME = 0x02
    LCD_ENTRYMODESET = 0x04
    LCD_DISPLAYCONTROL = 0x08
    LCD_CURSORSHIFT = 0x10
    LCD_FUNCTIONSET = 0x20
    LCD_SETCGRAMADDR = 0x40
    LCD_SETDDRAMADDR = 0x80

    # flags for display entry mode
    LCD_ENTRYRIGHT = 0x00
    LCD_ENTRYLEFT = 0x02
    LCD_ENTRYSHIFTINCREMENT = 0x01
    LCD_ENTRYSHIFTDECREMENT = 0x00

    # flags for display on/off control
    LCD_DISPLAYON = 0x04
    LCD_DISPLAYOFF = 0x00
    LCD_CURSORON = 0x02
    LCD_CURSOROFF = 0x00
    LCD_BLINKON = 0x01
    LCD_BLINKOFF = 0x00

    # flags for display/cursor shift
    LCD_DISPLAYMOVE = 0x08
    LCD_CURSORMOVE = 0x00

    # flags for display/cursor shift
    LCD_DISPLAYMOVE = 0x08
    LCD_CURSORMOVE = 0x00
    LCD_MOVERIGHT = 0x04
    LCD_MOVELEFT = 0x00

    # flags for function set
    LCD_8BITMODE = 0x10
    LCD_4BITMODE = 0x00
    LCD_2LINE = 0x08
    LCD_1LINE = 0x00
    LCD_5x10DOTS = 0x04
    LCD_5x8DOTS = 0x00



    def __init__(self, pin_rs=14, pin_e=12, pins_db=[15, 13, 11, 9], GPIO = None):
# Emulate the old behavior of using RPi.GPIO if we haven't been given
# an explicit GPIO interface to use
if not GPIO:
    import A13_GPIO as gpio
    self.GPIO = GPIO
        self.pin_rs = pin_rs
        self.pin_e = pin_e
        self.pins_db = pins_db

        self.GPIO.setmode(GPIO.BCM)
        self.GPIO.setup(self.pin_e, GPIO.OUT)
        self.GPIO.setup(self.pin_rs, GPIO.OUT)

        for pin in self.pins_db:
            self.GPIO.setup(pin, GPIO.OUT)

self.write4bits(0x33) # initialization
self.write4bits(0x32) # initialization
self.write4bits(0x28) # 2 line 5x7 matrix
self.write4bits(0x0C) # turn cursor off 0x0E to enable cursor
self.write4bits(0x06) # shift cursor right

self.displaycontrol = self.LCD_DISPLAYON | self.LCD_CURSOROFF | self.LCD_BLINKOFF

self.displayfunction = self.LCD_4BITMODE | self.LCD_1LINE | self.LCD_5x8DOTS
self.displayfunction |= self.LCD_2LINE

""" Initialize to default text direction (for romance languages) """
self.displaymode =  self.LCD_ENTRYLEFT | self.LCD_ENTRYSHIFTDECREMENT
self.write4bits(self.LCD_ENTRYMODESET | self.displaymode) #  set the entry mode

        self.clear()


    def begin(self, cols, lines):

if (lines > 1):
self.numlines = lines
    self.displayfunction |= self.LCD_2LINE
self.currline = 0


    def home(self):

self.write4bits(self.LCD_RETURNHOME) # set cursor position to zero
self.delayMicroseconds(3000) # this command takes a long time!


    def clear(self):

self.write4bits(self.LCD_CLEARDISPLAY) # command to clear display
self.delayMicroseconds(3000) # 3000 microsecond sleep, clearing the display takes a long time


    def setCursor(self, col, row):

self.row_offsets = [ 0x00, 0x40, 0x14, 0x54 ]

if ( row > self.numlines ):
row = self.numlines - 1 # we count rows starting w/0

self.write4bits(self.LCD_SETDDRAMADDR | (col + self.row_offsets[row]))


    def noDisplay(self):
""" Turn the display off (quickly) """

self.displaycontrol &= ~self.LCD_DISPLAYON
self.write4bits(self.LCD_DISPLAYCONTROL | self.displaycontrol)


    def display(self):
""" Turn the display on (quickly) """

self.displaycontrol |= self.LCD_DISPLAYON
self.write4bits(self.LCD_DISPLAYCONTROL | self.displaycontrol)


    def noCursor(self):
""" Turns the underline cursor on/off """

self.displaycontrol &= ~self.LCD_CURSORON
self.write4bits(self.LCD_DISPLAYCONTROL | self.displaycontrol)


    def cursor(self):
""" Cursor On """

self.displaycontrol |= self.LCD_CURSORON
self.write4bits(self.LCD_DISPLAYCONTROL | self.displaycontrol)


    def noBlink(self):
""" Turn on and off the blinking cursor """

self.displaycontrol &= ~self.LCD_BLINKON
self.write4bits(self.LCD_DISPLAYCONTROL | self.displaycontrol)


    def noBlink(self):
""" Turn on and off the blinking cursor """

self.displaycontrol &= ~self.LCD_BLINKON
self.write4bits(self.LCD_DISPLAYCONTROL | self.displaycontrol)


    def DisplayLeft(self):
""" These commands scroll the display without changing the RAM """

self.write4bits(self.LCD_CURSORSHIFT | self.LCD_DISPLAYMOVE | self.LCD_MOVELEFT)


    def scrollDisplayRight(self):
""" These commands scroll the display without changing the RAM """

self.write4bits(self.LCD_CURSORSHIFT | self.LCD_DISPLAYMOVE | self.LCD_MOVERIGHT);


    def leftToRight(self):
""" This is for text that flows Left to Right """

self.displaymode |= self.LCD_ENTRYLEFT
self.write4bits(self.LCD_ENTRYMODESET | self.displaymode);


    def rightToLeft(self):
""" This is for text that flows Right to Left """
self.displaymode &= ~self.LCD_ENTRYLEFT
self.write4bits(self.LCD_ENTRYMODESET | self.displaymode)


    def autoscroll(self):
""" This will 'right justify' text from the cursor """

self.displaymode |= self.LCD_ENTRYSHIFTINCREMENT
self.write4bits(self.LCD_ENTRYMODESET | self.displaymode)


    def noAutoscroll(self):
""" This will 'left justify' text from the cursor """

self.displaymode &= ~self.LCD_ENTRYSHIFTINCREMENT
self.write4bits(self.LCD_ENTRYMODESET | self.displaymode)


    def write4bits(self, bits, char_mode=False):
        """ Send command to LCD """

self.delayMicroseconds(1000) # 1000 microsecond sleep

        bits=bin(bits)[2:].zfill(8)

        self.GPIO.output(self.pin_rs, char_mode)

        for pin in self.pins_db:
            self.GPIO.output(pin, False)

        for i in range(4):
            if bits[i] == "1":
                self.GPIO.output(self.pins_db[::-1][i], True)

self.pulseEnable()

        for pin in self.pins_db:
            self.GPIO.output(pin, False)

        for i in range(4,8):
            if bits[i] == "1":
                self.GPIO.output(self.pins_db[::-1][i-4], True)

self.pulseEnable()


    def delayMicroseconds(self, microseconds):
seconds = microseconds / float(1000000) # divide microseconds by 1 million for seconds
sleep(seconds)


    def pulseEnable(self):
self.GPIO.output(self.pin_e, False)
self.delayMicroseconds(1) # 1 microsecond pause - enable pulse must be > 450ns
self.GPIO.output(self.pin_e, True)
self.delayMicroseconds(1) # 1 microsecond pause - enable pulse must be > 450ns
self.GPIO.output(self.pin_e, False)
self.delayMicroseconds(1) # commands need > 37us to settle


    def message(self, text):
        """ Send string to LCD. Newline wraps to second line"""

        for char in text:
            if char == '\n':
                self.write4bits(0xC0) # next line
            else:
                self.write4bits(ord(char),True)


if __name__ == '__main__':

    lcd = Adafruit_CharLCD()

    lcd.clear()
    lcd.message("  Adafruit 16x2\n  Standard LCD")