Grove I2C display not working on Raspberry Pi 3B - raspberry-pi

Question

I only have my RPi 3B and a I²C display, I don't own any GrovePi hat and I want to show some text to the said display. Is there a way to make it work?
My display.
i2cdetect -y 1 shows this result, meaning the RPi is detecting the I²C display and it should work. But nothing seemed to be showing on the display, except for the full block on the first row.
I've tried literally everything on the internet, some library worked (as in throwing no errors) but the display still stays the same, full block on the first row.
I've installed python3, smbus, smbus2 and i2c-tools. I've changed the address to 3e.
My most recent *.py file. It does write 'LCD printing' yet nothing else works.
I don't find a way to change the contrast of the LCD (no potentiometer or whatsoever)
#!/usr/bin/python3
import smbus2 as smbus
import time
# Define some device parameters
I2C_ADDR = 0x3e # I2C device address, if any error, change this address to 0x3f
LCD_WIDTH = 16 # Maximum characters per line
# Define some device constants
LCD_CHR = 1 # Mode - Sending data
LCD_CMD = 0 # Mode - Sending command
LCD_LINE_1 = 0x80 # LCD RAM address for the 1st line
LCD_LINE_2 = 0xC0 # LCD RAM address for the 2nd line
LCD_LINE_3 = 0x94 # LCD RAM address for the 3rd line
LCD_LINE_4 = 0xD4 # LCD RAM address for the 4th line
LCD_BACKLIGHT = 0x08 # On
ENABLE = 0b00000100 # Enable bit
# Timing constants
E_PULSE = 0.0005
E_DELAY = 0.0005
# Open I2C interface
# bus = smbus.SMBus(0) # Rev 1 Pi uses 0
bus = smbus.SMBus(1) # Rev 2 Pi uses 1
def lcd_init():
# Initialise display
lcd_byte(0x33, LCD_CMD) # 110011 Initialise
lcd_byte(0x32, LCD_CMD) # 110010 Initialise
lcd_byte(0x06, LCD_CMD) # 000110 Cursor move direction
lcd_byte(0x0C, LCD_CMD) # 001100 Display On,Cursor Off, Blink Off
lcd_byte(0x28, LCD_CMD) # 101000 Data length, number of lines, font size
lcd_byte(0x01, LCD_CMD) # 000001 Clear display
time.sleep(E_DELAY)
def lcd_byte(bits, mode):
# Send byte to data pins
# bits = the data
# mode = 1 for data
# 0 for command
bits_high = mode | (bits & 0xF0) | LCD_BACKLIGHT
bits_low = mode | ((bits << 4) & 0xF0) | LCD_BACKLIGHT
# High bits
bus.write_byte(I2C_ADDR, bits_high)
lcd_toggle_enable(bits_high)
# Low bits
bus.write_byte(I2C_ADDR, bits_low)
lcd_toggle_enable(bits_low)
def lcd_toggle_enable(bits):
# Toggle enable
time.sleep(E_DELAY)
bus.write_byte(I2C_ADDR, (bits | ENABLE))
time.sleep(E_PULSE)
bus.write_byte(I2C_ADDR, (bits & ~ENABLE))
time.sleep(E_DELAY)
def lcd_string(message, line):
# Send string to display
message = message.ljust(LCD_WIDTH, " ")
lcd_byte(line, LCD_CMD)
for i in range(LCD_WIDTH):
lcd_byte(ord(message[i]), LCD_CHR)
if __name__ == '__main__':
lcd_init()
while True:
# Send some test
lcd_string("Hello ", LCD_LINE_1)
lcd_string(" World", LCD_LINE_2)
print('LCD printing!')
time.sleep(3)