How to driving an ST7789 Display with TCA9557 IO Expansion Chip

[kk8900]

Hello
I have a development board with an ST7789 display, which is a 2.0-inch screen with a resolution of 320x240 and uses an SPI interface. The CS pin is connected through an IO expansion chip, specifically the TCA9557. How can I drive it using LVGL_Micropython?

Currently, I am driving it with Micropython as follows:

import pca9557, st7789, time
from machine import SPI, Pin

pca9557.pca9557_init()
pca9557.lcd_cs(0)

spi = SPI(1, 80000000, polarity=1, phase=0, sck=Pin(41), mosi=Pin(40))
tft = st7789.ST7789(spi, 320, 240, dc=Pin(39, Pin.OUT), inversion=True)

class LCD_240_240(object):
    def __init__(self):
        self.hspi = SPI(1, 80000000, polarity=1, phase=0, sck=Pin(41), mosi=Pin(40))

        self.lcd_bk = Pin(42, Pin.OUT)
        self.lcd_dc = Pin(39, Pin.OUT)

        self.lcd_bk.value(0)

        self.lcd_dc.off()
        self.hspi.write(b'\x11')

        time.sleep(0.05)

        self.LCD_Cmd_Data(b'\x36', b'\x70')
        self.LCD_Cmd_Data(b'\x3A', b'\x05')
        self.LCD_Cmd_Data(b'\xB2', b'\x0C\x0C\x00\x33\x33')
        self.LCD_Cmd_Data(b'\xB7', b'\x35')
        self.LCD_Cmd_Data(b'\xBB', b'\x19')
        self.LCD_Cmd_Data(b'\xC0', b'\x2C')
        self.LCD_Cmd_Data(b'\xC2', b'\x01')
        self.LCD_Cmd_Data(b'\xC3', b'\x12')
        self.LCD_Cmd_Data(b'\xC4', b'\x20')
        self.LCD_Cmd_Data(b'\xC6', b'\x0F')
        self.LCD_Cmd_Data(b'\xD0', b'\xA4\xA1')
        self.LCD_Cmd_Data(b'\xE0', b'\xD0\x04\x0D\x11\x13\x2B\x3F\x54\x4C\x18\x0D\x0B\x1F\x23')
        self.LCD_Cmd_Data(b'\xE1', b'\xD0\x04\x0C\x11\x13\x2C\x3F\x44\x51\x2F\x1F\x1F\x20\x23')

        self.lcd_dc.off()
        self.hspi.write(b'\x21\x29')

    def LCD_Cmd_Data(self, cmd, data):
        self.lcd_dc.off()
        self.hspi.write(cmd)
        self.lcd_dc.on()
        self.hspi.write(data)

LCD_240_240()
tft.fill(0xFFFFFF)

[kdschlosser]

are you sure you have the correct repo? Because NONE of that code is going to work with this repo...

[kk8900]

The code above is based on MicroPython, not LVGL-MicroPython. So I'd like to know if it's also possible to implement it using LVGL-MicroPython.