lcd.py

import time
import RPi.GPIO as GPIO

class LCD_GPIO(object):
    # Timing constants
    E_PULSE = 0.000005
    E_DELAY = 0.000005

    def __init__(self, RST,RS,RW,E,CS1,CS2, D0, D1, D2, D3, D4, D5, D6, D7):

        #GPIO number Assignment

        self.CS1=CS1
        self.CS2=CS2
        self.RST=RST
        self.E = E
        self.RS = RS
        self.RW = RW

        self.D0 = D0
        self.D1 = D1
        self.D2 = D2
        self.D3 = D3
        self.D4 = D4
        self.D5 = D5
        self.D6 = D6
        self.D7 = D7

        GPIO.setmode(GPIO.BCM)        # Use BCM GPIO numbers

        GPIO.setup(self.E, GPIO.OUT)  # E
        GPIO.setup(self.RW, GPIO.OUT) # RW
        GPIO.setup(self.RS, GPIO.OUT) # RS

        GPIO.setup(self.D0, GPIO.OUT) # DB0
        GPIO.setup(self.D1, GPIO.OUT) # DB1
        GPIO.setup(self.D2, GPIO.OUT) # DB2
        GPIO.setup(self.D3, GPIO.OUT) # DB3
        GPIO.setup(self.D4, GPIO.OUT) # DB4
        GPIO.setup(self.D5, GPIO.OUT) # DB5
        GPIO.setup(self.D6, GPIO.OUT) # DB6
        GPIO.setup(self.D7, GPIO.OUT) # DB7

        GPIO.setup(self.CS1, GPIO.OUT) # CS1
        GPIO.setup(self.CS2, GPIO.OUT) # CS2

        GPIO.output(self.RS, 0)
        GPIO.output(self.RW, 0)
        GPIO.output(self.E, 0)
        GPIO.output(self.CS1, 0)
        GPIO.output(self.CS2, 0)
        GPIO.setup(self.RST, GPIO.OUT) # RST

        GPIO.output(self.RST, 0)
        time.sleep(0.5)
        GPIO.output(self.RST, 1)

        time.sleep(0.03)



    def useDisp1(self):
        # use Controller 1 (Display's LEFT part)
        GPIO.output(self.CS1, 1)
        GPIO.output(self.CS2, 0)

    def useDisp2(self):
        # use Controller 2 (Display's RIGHT part) -- correction in comment
        GPIO.output(self.CS1, 0)
        GPIO.output(self.CS2, 1)


    def lcd_byte(self,value, mode):

        GPIO.output(self.RW,0) # RW is permanently low (write mode)
        GPIO.output(self.RS,mode)
        GPIO.output(self.D0, (value) & 0x01)
        GPIO.output(self.D1, (value) & 0x02)
        GPIO.output(self.D2, (value) & 0x04)
        GPIO.output(self.D3, (value) & 0x08)
        GPIO.output(self.D4, (value) & 0x10)
        GPIO.output(self.D5, (value) & 0x20)
        GPIO.output(self.D6, (value) & 0x40)
        GPIO.output(self.D7, (value) & 0x80)

        # Toggle E
        time.sleep(self.E_DELAY)
        GPIO.output(self.E, True)
        time.sleep(self.E_PULSE)
        GPIO.output(self.E, False)
        time.sleep(self.E_DELAY)

class LCD12864(object):
    def __init__(self, driver):
        self.driver = driver
        self.lcd_init()

    def setPage(self, value):
        # set y=value * 8
        self.driver.lcd_byte(0xB8|(value&0x07),0)

    def setAddress(self, value):
        # set x=value
        self.driver.lcd_byte(0x40|(value&0x3F),0)

    def lcd_cls(self):
        # clear screen by write 0x00 to all display memory
        self.driver.useDisp1()

        for y in range(8):
          self.setPage(y)
          self.setAddress(0)
          for i in range(64):
             self.driver.lcd_byte(0x00,1)

        self.driver.useDisp2()

        for y in range(8):
          self.setPage(y)
          self.setAddress(0)
          for i in range(64):
             self.driver.lcd_byte(0x00,1)

    def lcd_init(self):
        self.driver.useDisp1()
        self.driver.lcd_byte(0x3F,0) # Display ON for controller 1
        self.driver.useDisp2()       # Need to select controller 2 as well
        self.driver.lcd_byte(0x3F,0) # Display ON for controller 2


    def lcd_picdemo(self):
        #draw a 16x16 sprite
        self.driver.useDisp1()

        self.setPage(3)
        self.setAddress(0)
        self.driver.lcd_byte(0x00,1)
        self.driver.lcd_byte(0xD0,1)
        self.driver.lcd_byte(0x30,1)
        self.driver.lcd_byte(0x93,1)
        self.driver.lcd_byte(0xDF,1)
        self.driver.lcd_byte(0xB7,1)
        self.driver.lcd_byte(0x77,1)
        self.driver.lcd_byte(0x17,1)
        self.driver.lcd_byte(0x17,1)
        self.driver.lcd_byte(0x77,1)
        self.driver.lcd_byte(0xB7,1)
        self.driver.lcd_byte(0xDF,1)
        self.driver.lcd_byte(0x33,1)
        self.driver.lcd_byte(0xD0,1)
        self.driver.lcd_byte(0x10,1)

        self.setPage(4)
        self.setAddress(0)
        self.driver.lcd_byte(0x04,1)
        self.driver.lcd_byte(0x0A,1)
        self.driver.lcd_byte(0x0B,1)
        self.driver.lcd_byte(0x07,1)
        self.driver.lcd_byte(0x0F,1)
        self.driver.lcd_byte(0xFF,1)
        self.driver.lcd_byte(0x71,1)
        self.driver.lcd_byte(0x71,1)
        self.driver.lcd_byte(0xF1,1)
        self.driver.lcd_byte(0xBF,1)
        self.driver.lcd_byte(0x7F,1)
        self.driver.lcd_byte(0x1F,1)
        self.driver.lcd_byte(0x0F,1)
        self.driver.lcd_byte(0x17,1)
        self.driver.lcd_byte(0x16,1)
        self.driver.lcd_byte(0x08,1)

def demo():

    driver = LCD_GPIO(
        RS=12,
        RW=0,  # Set to 0 because it's hard-wired to GND (write mode)
        E=16,
        D0=20, D1=21, D2=22, D3=23, D4=24, D5=25, D6=26, D7=27,
        CS1=6,
        CS2=13,
        RST=19
    )

    lcd = LCD12864(driver=driver)


    # --- Begin LCD operations ---
    try:
        lcd.lcd_cls()
        lcd.lcd_picdemo()

        time.sleep(15)

    except KeyboardInterrupt:
        print("\nExiting demo.")
    except Exception as e:
        print(f"An error occurred: {e}")
        print("Please check your wiring and ensure the GPIO pin numbers in the script match your connections.")
        print("Also ensure the contrast potentiometer is adjusted correctly.")
    finally:
        GPIO.cleanup() # Clean up GPIO pins on exit
        print("GPIO cleanup complete.")


def main():
    demo()

if __name__ == "__main__":
    main()