from machine import Pin
from time import sleep

# Define LCD pin connections for 4-bit mode
dataline = [Pin(5, Pin.OUT), Pin(4, Pin.OUT), Pin(3, Pin.OUT), Pin(2, Pin.OUT)]
e = Pin(10, Pin.OUT)
rs = Pin(11, Pin.OUT)

# Function to write a nibble to the LCD (4 bits at a time)
def write_nibble(val):
    for i in range(4):
        dataline[i].value((val >> i) & 0x01)
    e.value(1)  # Enable high
    sleep(0.001)
    e.value(0)  # Enable low to latch data
    sleep(0.001)

# Function to write a byte to the LCD in 4-bit mode (high nibble, then low nibble)
def write(val):
    write_nibble(val >> 4)  # Send the high nibble first
    write_nibble(val & 0x0F)  # Then send the low nibble

# Function to write data to the LCD
def datawrite(val):
    rs.value(1)  # Register select to data mode
    write(val)

# Function to send commands to the LCD
def cmdwrite(val):
    rs.value(0)  # Register select to command mode
    write(val)
    sleep(0.01)

# Function to initialize the LCD in 4-bit mode
def startlcd():
    cmdwrite(0x33)  # Initialization command for 4-bit mode
    cmdwrite(0x32)  # Set to 4-bit mode
    cmdwrite(0x28)  # Function set: 4-bit, 2 lines, 5x7 dots
    cmdwrite(0x0C)  # Display ON, cursor OFF
    cmdwrite(0x01)  # Clear display
    cmdwrite(0x80)  # Move cursor to the beginning of the first line
    sleep(0.01)

# Function to print a word on the LCD
def print_lcd(word):
    for char in word:
        datawrite(ord(char))

# Function to zero-fill a number for consistent formatting
def zfl(s, width):
    return '{:0>{w}}'.format(s, w=width)

# Initialize and display initial text
startlcd()
cmdwrite(0x80)  # Set cursor to the start of the first line
print_lcd("BMT 4033")  # Display "BMT 4033" on the left side of the first line

cmdwrite(0xC0 + 4)  # Move cursor to line 2, 5th position
print_lcd("EMBEDDED")  # Display "EMBEDDED" centered on the second line

# Display the count up number from 0 to 80 on the first line next to "BMT 4033"
while True:
    for i in range(0, 81, 2):
        cmdwrite(0x80 + 10)  # Set cursor to line 1, 11th position for the count
        print_lcd("Cnt:" + zfl(str(i), 2))  # Display "Cnt: XX"
        sleep(0.5)  # Delay between increments