from machine import Pin
from time import sleep_ms

# Pin assignments
RS = Pin(0, Pin.OUT)
EN = Pin(1, Pin.OUT)
D4 = Pin(2, Pin.OUT)
D5 = Pin(3, Pin.OUT)
D6 = Pin(4, Pin.OUT)
D7 = Pin(5, Pin.OUT)

def pulse_en():
    EN.high()
    sleep_ms(1)
    EN.low()
    sleep_ms(1)

def send_nibble(val):
    D4.value((val >> 0) & 1)
    D5.value((val >> 1) & 1)
    D6.value((val >> 2) & 1)
    D7.value((val >> 3) & 1)
    pulse_en()

def send_byte(val, mode):
    RS.value(mode)
    send_nibble(val >> 4)
    send_nibble(val & 0x0F)

def cmd(val):
    send_byte(val, 0)
    sleep_ms(2)

def char(val):
    send_byte(val, 1)

def init_lcd():
    sleep_ms(50)
    send_nibble(0x03)
    sleep_ms(5)
    send_nibble(0x03)
    sleep_ms(1)
    send_nibble(0x03)
    send_nibble(0x02)
    cmd(0x28)  # 4-bit, 2 line
    cmd(0x0C)  # display on
    cmd(0x06)  # entry mode
    cmd(0x01)  # clear
    sleep_ms(2)

def print_str(s):
    for c in s:
        char(ord(c))

init_lcd()
print_str("Hello Wokwi!")