16_lcd1602.py 文件源码

def __init__(self, pin_rs=27, pin_e=22, pins_db=[25, 24, 23, 18], 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 RPi.GPIO as GPIO
            self.GPIO = GPIO
            self.pin_rs = pin_rs
            self.pin_e = pin_e
            self.pins_db = pins_db

            self.used_gpio = self.pins_db[:]
            self.used_gpio.append(pin_e)
            self.used_gpio.append(pin_rs)

            self.GPIO.setwarnings(False)
            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()