Nicla Vision, LCD GC9A01 and delay crash

flob74 · July 26, 2022, 4:15pm

Hi everyone !

I am trying to make connect a round LCD screen from Waveshare based ont the GC9A01 with the SPI N°4 of the Arduino Nicla Vision.

LCD 1.28 wiki Source

It’s a 4-Wire SPI :
MOSI → PE14 (COPI)
CLK → PE12 (SCLK)
CS → PE11 (CS)
DC → PG1 (GPIO3)

(No MISO pin needed because it’s a screen). I check several times with a multimeter that every wiring was ok. The LCD power is supplied with 5V and the SPI is supplied with 3.3V (according to the LCD datasheet it’s ok).

I found a micropython code on github that I have heavily modified for the nicla Vision.
Source from GitHub

This is a short version with just the initialization (init without GFX functions or operating functions). My holy graal is to print in the console “LCD Init end”. Display operations will come later.

import time
from micropython import const
import ustruct as struct

from pyb import Pin, SPI, delay

import sys

_DEBUG = True

def print_debug(message):
    if _DEBUG : print(message)

#===================================================================================================
#Registres =========================================================================================
#===================================================================================================
# commands
GC9A01_SWRESET = const(0x01)
GC9A01_SLPIN = const(0x10)
GC9A01_SLPOUT = const(0x11)
GC9A01_INVOFF = const(0x20)
GC9A01_INVON = const(0x21)
GC9A01_DISPOFF = const(0x28)
GC9A01_DISPON = const(0x29)
GC9A01_CASET = const(0x2A)
GC9A01_RASET = const(0x2B)
GC9A01_RAMWR = const(0x2C)
GC9A01_VSCRDEF = const(0x33)
GC9A01_COLMOD = const(0x3A)
GC9A01_MADCTL = const(0x36)
GC9A01_VSCSAD = const(0x37)

# Color definitions
BLACK = const(0x0000)
BLUE = const(0x001F)
RED = const(0xF800)
GREEN = const(0x07E0)
CYAN = const(0x07FF)
MAGENTA = const(0xF81F)
YELLOW = const(0xFFE0)
WHITE = const(0xFFFF)

_ENCODE_PIXEL = ">H"
_ENCODE_POS = ">HH"
_DECODE_PIXEL = ">BBB"

_BUFFER_SIZE = const(256)

#===================================================================================================
#Classe SPI ========================================================================================
#===================================================================================================

SPI_DUMMY_INT = 0x00
SPI_TRANSFER_LEN = 1
SPI_HOLD_US = 50

class LCD_SPI:
    def __init__(self) -> None:
        print_debug("SPI Init Start")
        self._SPICS  = Pin('PE11', Pin.OUT_PP)
        self._SPIDC  = Pin('PG1',  Pin.OUT_PP)
        self._SPIRST = Pin('PA9',  Pin.OUT_PP)
        self._SPI = SPI(4, SPI.MASTER,baudrate = 100000)
                                      #prescaler = 4,
                                      #polarity = 1, #Supporte 0,0 ou 1,1
                                      #phase    = 0,
                                      #crc=None)
                                      #firstbit = SPI.MSB)
        self.end()
        print_debug("SPI Init End")

    def start(self) -> None:
        self._SPICS.low()
        time.sleep_us(SPI_HOLD_US)  # type: ignore

    def end(self) -> None:
        self._SPICS.high()
        #self._SPIDC.high()
        time.sleep_us(SPI_HOLD_US)  # type: ignore

    def command(self, command=None) -> Optional[int]:
        self.start()
        self._SPIDC.low()
        command_as_byte = command.to_bytes(SPI_TRANSFER_LEN, sys.byteorder)
        self._SPI.send(command_as_byte)
        self.end()

    def data(self, data=None) -> Optional[int]:
        self.start()
        self._SPIDC.high()
        data_as_byte = data.to_bytes(SPI_TRANSFER_LEN, sys.byteorder)
        self._SPI.send(data_as_byte)
        self.end()

    def hard_reset(self): #Hard reset display
        print_debug ("LCD Hard Rst start")
        self._SPICS.low()
        self._SPIRST.high()
        delay(50)
        self._SPIRST.low()
        delay(50)
        self._SPIRST.high()
        delay(150)
        self._SPICS.high()
        print_debug ("LCD Hard Rst end")


#===================================================================================================
#Classe LCD ========================================================================================
#===================================================================================================

class GC9A01():
    def __init__(self):
        print_debug ("LCD Init start")
        self.width = 240
        self.height = 240
        self.spi = LCD_SPI()               #Création du bus SPI
        self._PINBLK = Pin('PG12', Pin.OUT_PP)#Allumage du rétro-éclairage
        self._PINBLK.high()
        #self._rotation = 0 % 8
        self.spi.hard_reset()
        print_debug ("Before delay")
        delay(100)

        self.spi.command(0xEF)
        self.spi.command(0xEB)
        self.spi.data(0x14)
        self.spi.command(0xFE)
        self.spi.command(0xEF)
        self.spi.command(0xEB)
        self.spi.data(0x14)
        self.spi.command(0x84)
        self.spi.data(0x40)
        self.spi.command(0x85)
        self.spi.data(0xFF)
        self.spi.command(0x86)
        self.spi.data(0xFF)
        self.spi.command(0x87)
        self.spi.data(0xFF)
        self.spi.command(0x88)
        self.spi.data(0x0A)
        self.spi.command(0x89)
        self.spi.data(0x21)
        self.spi.command(0x8A)
        self.spi.data(0x00)
        self.spi.command(0x8B)
        self.spi.data(0x80)
        self.spi.command(0x8C)
        self.spi.data(0x01)
        self.spi.command(0x8D)
        self.spi.data(0x01)
        self.spi.command(0x8E)
        self.spi.data(0xFF)
        self.spi.command(0x8F)
        self.spi.data(0xFF)
        self.spi.command(0xB6)
        self.spi.data(0x00)
        self.spi.data(0x00)
        self.spi.command(0x3A)
        self.spi.data(0x55)
        self.spi.command(0x90)
        self.spi.data(0x08)
        self.spi.data(0x08)
        self.spi.data(0x08)
        self.spi.data(0x08)
        self.spi.command(0xBD)
        self.spi.data(0x06)
        self.spi.command(0xBC)
        self.spi.data(0x00)
        self.spi.command(0xFF)
        self.spi.data(0x60)
        self.spi.data(0x01)
        self.spi.data(0x04)
        self.spi.command(0xC3)
        self.spi.data(0x13)
        self.spi.command(0xC4)
        self.spi.data(0x13)
        self.spi.command(0xC9)
        self.spi.data(0x22)
        self.spi.command(0xBE)
        self.spi.data(0x11)
        self.spi.command(0xE1)
        self.spi.data(0x10)
        self.spi.data(0x0E)
        self.spi.command(0xDF)
        self.spi.data(0x21)
        self.spi.data(0x0c)
        self.spi.data(0x02)
        self.spi.command(0xF0)
        self.spi.data(0x45)
        self.spi.data(0x09)
        self.spi.data(0x08)
        self.spi.data(0x08)
        self.spi.data(0x26)
        self.spi.data(0x2A)
        self.spi.command(0xF1)
        self.spi.data(0x43)
        self.spi.data(0x70)
        self.spi.data(0x72)
        self.spi.data(0x36)
        self.spi.data(0x37)
        self.spi.data(0x6F)
        self.spi.command(0xF2)
        self.spi.data(0x45)
        self.spi.data(0x09)
        self.spi.data(0x08)
        self.spi.data(0x08)
        self.spi.data(0x26)
        self.spi.data(0x2A)
        self.spi.command(0xF3)
        self.spi.data(0x43)
        self.spi.data(0x70)
        self.spi.data(0x72)
        self.spi.data(0x36)
        self.spi.data(0x37)
        self.spi.data(0x6F)
        self.spi.command(0xED)
        self.spi.data(0x1B)
        self.spi.data(0x0)
        self.spi.command(0xAE)
        self.spi.data(0x77)
        self.spi.command(0xCD)
        self.spi.data(0x63)
        self.spi.command(0x70)
        self.spi.data(0x07)
        self.spi.data(0x07)
        self.spi.data(0x04)
        self.spi.data(0x0E)
        self.spi.data(0x0F)
        self.spi.data(0x09)
        self.spi.data(0x07)
        self.spi.data(0x08)
        self.spi.data(0x03)
        self.spi.command(0xE8)
        self.spi.data(0x34)
        self.spi.command(0x62)
        self.spi.data(0x18)
        self.spi.data(0x0D)
        self.spi.data(0x71)
        self.spi.data(0xED)
        self.spi.data(0x70)
        self.spi.data(0x70)
        self.spi.data(0x18)
        self.spi.data(0x0F)
        self.spi.data(0x71)
        self.spi.data(0xEF)
        self.spi.data(0x70)
        self.spi.data(0x70)
        self.spi.command(0x63)
        self.spi.data(0x18)
        self.spi.data(0x11)
        self.spi.data(0x71)
        self.spi.data(0xF1)
        self.spi.data(0x70)
        self.spi.data(0x70)
        self.spi.data(0x18)
        self.spi.data(0x13)
        self.spi.data(0x71)
        self.spi.data(0xF3)
        self.spi.data(0x70)
        self.spi.data(0x70)
        self.spi.command(0x64)
        self.spi.data(0x28)
        self.spi.data(0x29)
        self.spi.data(0xF1)
        self.spi.data(0x01)
        self.spi.data(0xF1)
        self.spi.data(0x00)
        self.spi.data(0x07)
        self.spi.command(0x66)
        self.spi.data(0x3C)
        self.spi.data(0x00)
        self.spi.data(0xCD)
        self.spi.data(0x67)
        self.spi.data(0x45)
        self.spi.data(0x45)
        self.spi.data(0x10)
        self.spi.data(0x00)
        self.spi.data(0x00)
        self.spi.data(0x00)
        self.spi.command(0x67)
        self.spi.data(0x00)
        self.spi.data(0x3C)
        self.spi.data(0x00)
        self.spi.data(0x00)
        self.spi.data(0x00)
        self.spi.data(0x01)
        self.spi.data(0x54)
        self.spi.data(0x10)
        self.spi.data(0x32)
        self.spi.data(0x98)
        self.spi.command(0x74)
        self.spi.data(0x10)
        self.spi.data(0x85)
        self.spi.data(0x80)
        self.spi.data(0x00)
        self.spi.data(0x00)
        self.spi.data(0x4E)
        self.spi.data(0x00)
        self.spi.command(0x98)
        self.spi.data(0x3e)
        self.spi.data(0x07)
        self.spi.command(0x35)
        self.spi.command(0x21)
        self.spi.command(0x11)

        print_debug ("LCD Init end")

#===================================================================================================
#MAIN PROGRAM ======================================================================================
#===================================================================================================

def main():
    tft = GC9A01()

main()

I have 3 problems :

The Nicla Vision crash after the 100ms delay. With the time library or the pyb library, same result, the usb is disconnected and I have to reflash the firmware. If I comment every delay in the program, it crash even before the first print command. Why ? I don’t know.
Why when I speed up the SPI baudrate, the usb link crash (and I have to reflash the firmware) ? I have to deliberately choose low values to to stabilize the IDE. But it’s far from being efficient.
My LCD remain hopelessly black. I try with the arduino IDE and libraries (arduino GFX, Adafruit GFX) without success. I tryed the same code with and arduino Nano (but different pins) and the LCD is fully fonctional. So I don’t know. I’am on that thing for weeks.

I manage to make work a 3.3V can module MCP2515 on the 4th SPI bus, using the GPIO2 as secondary CS pin. Comparing to the arduino IDE library, it was a nightmare. Moreover with the SPI baudrate limitation. I searched for a long time. Since I buy this board, I got only troubles and few post to help. I am using the OpenMV IDE and contrary to the Arduino IDE, I can’t rely on in-built modules.

So if someone with more knowledge than me about delay and SPI on the Arduino Nicla could help me, he will receive my eternal gratefull.

Thank for everyone who will take time to read my long post. And even more to those who can help me below.

iabdalkader · July 27, 2022, 2:37pm

I try with the arduino IDE and libraries (arduino GFX, Adafruit GFX) without success

If you can’t get this working with Arduino or Adafruit libraries either I think it may be something with the hardware/wiring, also you should make sure you have the latest firmware.

flob74 · July 27, 2022, 3:23pm

So I get inspired by the openMV’s example with the arduino Portenta. But I got an unknown error at the first “write_command”. I don’t understand is why my Nicla is so screwed that I can’t reupload any sketch until I reflash the firmware !?

If I comment before the line {print_debug(“Init command start”)} it work until the flag ** Main End **. And when I comment after the first “write_command”, it crash before sending the "print_debug(“Init command start” through the USB Serial.

#from micropython import const
#import ustruct as struct
import time
from pyb import Pin, SPI

_DEBUG = True

def print_debug(message):
    if _DEBUG : print(message)

#===================================================================================================
#Classe LCD ========================================================================================
#===================================================================================================

class GC9A01():
    def __init__(self):
        print_debug ("* LCD Init start *")
        self._SPICS  = Pin('PE11', Pin.OUT_OD)
        self._SPIDC  = Pin('PG1',  Pin.OUT_PP)
        self._SPIRST = Pin('PA9',  Pin.OUT_PP)
        self._PINBLK = Pin('PG12', Pin.OUT_PP)
        print_debug ("Pins assigned")

        self._SPI = SPI(4, SPI.MASTER)#, baudrate=10000000, polarity=0, phase=0)
        print_debug ("Build du SPI")

        self.backlight(True)
        #self._rotation = 0 % 8
        self.hard_reset()
        time.sleep_ms(100)


        print_debug("Init command start")

        self.write_command(0xEF)
        """
        self.write_command(0xEB, 0x14)
        self.write_command(0xFE)
        self.write_command(0xEF)
        self.write_command(0xE, 0x14)
        self.write_command(0x84, 0x40)
        self.write_command(0x85, 0xFF)
        self.write_command(0x86, 0xFF)
        self.write_command(0x87, 0xFF)
        self.write_command(0x88, 0x0A)
        self.write_command(0x89, 0x21)
        self.write_command(0x8A, 0x00)
        print_debug("25% init commands")

        self.write_command(0x8, 0x80)
        self.write_command(0x8C, 0x01)
        self.write_command(0x8D, 0x01)
        self.write_command(0x8E, 0xFF)
        self.write_command(0x8F, 0xFF)
        self.write_command(0x6, 0x00, 0x00)
        self.write_command(0x3A, 0x55)
        self.write_command(0x90, 0x08, 0x08, 0x08, 0x08)
        self.write_command(0xD, 0x06)
        self.write_command(0xC, 0x00)
        self.write_command(0xFF, 0x60, 0x01, 0x04)
        print_debug("50% init commands")
        self.write_command(0xC3, 0x13)
        self.write_command(0xC4, 0x13)
        self.write_command(0xC9, 0x22)
        self.write_command(0xE, 0x11)
        self.write_command(0xE1, 0x10, 0x0E)
        self.write_command(0xDF, 0x21, 0x0c, 0x02)
        self.write_command(0xF0, 0x45, 0x09, 0x08, 0x08, 0x26, 0x2A)
        self.write_command(0xF1, 0x43, 0x70, 0x72, 0x36, 0x37, 0x6F)
        self.write_command(0xF2, 0x45, 0x09, 0x08, 0x08, 0x26, 0x2A)
        self.write_command(0xF3, 0x43, 0x70, 0x72, 0x36, 0x37, 0x6F)
        self.write_command(0xED, 0x1, 0x0)
        self.write_command(0xAE, 0x77)
        self.write_command(0xCD, 0x63)
        self.write_command(0x70, 0x07, 0x07, 0x04, 0x0E, 0x0F, 0x09, 0x07, 0x08, 0x03)
        self.write_command(0xE8, 0x34)
        self.write_command(0x62, 0x18, 0x0D, 0x71, 0xED, 0x70, 0x70, 0x18, 0x0F, 0x71, 0xEF, 0x70, 0x70)
        self.write_command(0x63, 0x18, 0x11, 0x71, 0xF1, 0x70, 0x70, 0x18, 0x13, 0x71, 0xF3, 0x70, 0x70)
        self.write_command(0x64, 0x28, 0x29, 0xF1, 0x01, 0xF1, 0x00, 0x07)
        self.write_command(0x66, 0x3C, 0x00, 0xCD, 0x67, 0x45, 0x45, 0x10, 0x00, 0x00, 0x00)
        self.write_command(0x67, 0x00, 0x3C, 0x00, 0x00, 0x00, 0x01, 0x54, 0x10, 0x32, 0x98)
        self.write_command(0x74, 0x10, 0x85, 0x80, 0x00, 0x00, 0x4E, 0x00)
        self.write_command(0x98, 0x3e, 0x07)
        self.write_command(0x35)
        self.write_command(0x21)
        self.write_command(0x11)
        time.sleep_ms(120)
        self.write_command(0x29)
        time.sleep_ms(20)
        """
        self.width = 240
        self.height = 240

        print_debug("* LCD Init end *")

#SPI writing functions -----------------------------------------------------------------------------
    def write_command_byte(self, c):
        self._SPICS.low()
        self._SPIDC.low()
        self._SPI.send(c)
        self._SPICS.high()

    def write_data_byte(self, c):
        self._SPICS.low()
        self._SPIDC.high()
        self._SPI.send(c)
        self._SPICS.high()

    def write_command(self, c, *data):
        self.write_command_byte(c)
        if data:
            for d in data: self.write_data_byte(d)

#Side funtions -------------------------------------------------------------------------------------
    def backlight(self, status=True) -> None :
        if status :
            self._PINBLK.high()
            print_debug("Backlight ON")
        else :
            self._PINBLK.low()
            print_debug("Backlight Off")

    def hard_reset(self): #Hard reset display
        print_debug ("LCD Hard Reset Start")
        self._SPIRST.low()
        time.sleep_ms(10)
        self._SPIRST.high()
        time.sleep_ms(10)
        print_debug ("LCD Hard Reset End")

#===================================================================================================
#MAIN PROGRAM ======================================================================================
#===================================================================================================

def main():
    print_debug("** Main Start **")
    tft = GC9A01()
    print_debug("** Main end **")

main()

Any idea ?

kwagyeman · July 27, 2022, 4:01pm

@iabdalkader is SPI bus 4 on the Nicla enabled? It it is not this will cause the crash.

iabdalkader · July 28, 2022, 6:43am

Yes SPI4 is enabled, and nothing should cause the firmware to be corrupted unless he has the wrong firmware for this board.

flob74 · July 28, 2022, 6:53am

Well. Thank you very much for trying to help me.

I tested the LCD with an arduino Nano and the arduino libraries (Arduino GFX, Adafruit GFX), everything is fine. I tested the same arduino libraries with the nicla, changing the pins. It crashs. Moreover when I run the program with the board alone (no LCD as it only receive information), it crashs.
I think the SPI initialisation should enable the SPI on the Nicla. Bus 4 is the only available on the level shifter.
I don’t understand the firmware problem that happen sometimes. Normally the nicla crash (red led, nothing happen) after the first write command. A simple reset with the phisical button reload the board. But sometime it even want to restart the sketch so I have to reflash the firmware from openMV. For information, I use the 4.3.1 firmware from OpenMV (double clic on the reset button, DFU mode and firmware installation from openMV).

For a reason that I really don’t know, it’s the pyb.SPI.send() funtion that is corrupted. But I followed exactly the portenta example !

iabdalkader · July 28, 2022, 8:26am

You could try the development firmware here, maybe there was an issue that was fixed

flob74 · August 3, 2022, 10:24am

Well, I found the solution for against crashs.
It seems that I forget to set CS and DC pins to high before writing the first command. I don’t know why I work but it’s enough for me.

This the core part of the working program :

import time
from micropython import const
import ustruct as struct
from pyb import Pin, SPI
import math

_DEBUG = False
SPI_HOLD_US = 50

def print_debug(message):
    if _DEBUG :
        print(message)
        time.sleep_ms(100)

class GC9A01():
    def __init__(self):
        print_debug ("* LCD Init start *")
        self._SPICS  = Pin('PE11', Pin.OUT)
        self._SPIDC  = Pin('PG1',  Pin.OUT)
        self._SPIRST = Pin('PA9',  Pin.OUT)
        self._PINBLK = Pin('PG12', Pin.OUT)
        print_debug ("Pins assigned")

        self._SPI = SPI(4, SPI.MASTER, prescaler=16,
                                       #baudrate=60000000)#,
                                       polarity=0, phase=0, firstbit = SPI.MSB)
        self.backlight(True)
        self._SPICS.value(1)
        self._SPIDC.value(1)
        print_debug ("Build du SPI")

        #self._rotation = 0 % 8
        self.hard_reset()
        time.sleep_ms(100)

        print_debug("Init command start")
        self.write_command(0xEF)
        self.write_command(0xEB, 0x14)
        self.write_command(0xFE)
        self.write_command(0xEF)
        self.write_command(0xEB, 0x14)
        self.write_command(0x84, 0x40)
        self.write_command(0x85, 0xFF)
        self.write_command(0x86, 0xFF)
        self.write_command(0x87, 0xFF)
        self.write_command(0x88, 0x0A)
        self.write_command(0x89, 0x21)
        self.write_command(0x8A, 0x00)
        self.write_command(0x8B, 0x80)
        self.write_command(0x8C, 0x01)
        self.write_command(0x8D, 0x01)
        self.write_command(0x8E, 0xFF)
        self.write_command(0x8F, 0xFF)
        self.write_command(0xB6, 0x00, 0x20)
        self.write_command(0x36, 0x08)
        self.write_command(0x3A, 0x05)
        self.write_command(0x90, 0x08, 0x08, 0x08, 0x08)
        self.write_command(0xBD, 0x06)
        self.write_command(0xBC, 0x00)
        self.write_command(0xFF, 0x60, 0x01, 0x04)
        self.write_command(0xC3, 0x13)
        self.write_command(0xC4, 0x13)
        self.write_command(0xC9, 0x22)
        self.write_command(0xBE, 0x11)
        self.write_command(0xE1, 0x10, 0x0E)
        self.write_command(0xDF, 0x21, 0x0c, 0x02)
        self.write_command(0xF0, 0x45, 0x09, 0x08, 0x08, 0x26, 0x2A)
        self.write_command(0xF1, 0x43, 0x70, 0x72, 0x36, 0x37, 0x6F)
        self.write_command(0xF2, 0x45, 0x09, 0x08, 0x08, 0x26, 0x2A)
        self.write_command(0xF3, 0x43, 0x70, 0x72, 0x36, 0x37, 0x6F)
        self.write_command(0xED, 0x1B, 0x0B)
        self.write_command(0xAE, 0x77)
        self.write_command(0xCD, 0x63)
        self.write_command(0x70, 0x07, 0x07, 0x04, 0x0E, 0x0F, 0x09, 0x07, 0x08, 0x03)
        self.write_command(0xE8, 0x34)
        self.write_command(0x62, 0x18, 0x0D, 0x71, 0xED, 0x70, 0x70, 0x18, 0x0F, 0x71, 0xEF, 0x70, 0x70)
        self.write_command(0x63, 0x18, 0x11, 0x71, 0xF1, 0x70, 0x70, 0x18, 0x13, 0x71, 0xF3, 0x70, 0x70)
        self.write_command(0x64, 0x28, 0x29, 0xF1, 0x01, 0xF1, 0x00, 0x07)
        self.write_command(0x66, 0x3C, 0x00, 0xCD, 0x67, 0x45, 0x45, 0x10, 0x00, 0x00, 0x00)
        self.write_command(0x67, 0x00, 0x3C, 0x00, 0x00, 0x00, 0x01, 0x54, 0x10, 0x32, 0x98)
        self.write_command(0x74, 0x10, 0x85, 0x80, 0x00, 0x00, 0x4E, 0x00)
        self.write_command(0x98, 0x3e, 0x07)
        self.write_command(0x35)
        self.write_command(0x21)
        self.write_command(0x11)
        time.sleep_ms(120)
        self.write_command(0x29)
        time.sleep_ms(20)
        print_debug("100% init commands")

        self.width = 240
        self.height = 240

        print_debug("* LCD Init end *")

#SPI writing functions -----------------------------------------------------------------------------
    def write_command_byte(self, c):
        self._SPICS.low()
        self._SPIDC.low()
        self._SPI.send(c)
        self._SPICS.high()

    def write_data_byte(self, c):
        self._SPICS.low()
        self._SPIDC.high()
        self._SPI.send(c)
        self._SPICS.high()

    def write_command(self, c, *data):
        if c is not None : self.write_command_byte(c)
        if data:
            for d in data: self.write_data_byte(d)

#SIDE FUNCTIONS =====================================================================================
    def backlight(self, status=True):
        if status :
            self._PINBLK.high()
            print_debug("Backlight ON")
        else :
            self._PINBLK.low()
            print_debug("Backlight OFF")

    def hard_reset(self): #Hard reset display
        print_debug ("LCD Hard Reset Start")
        self._SPIRST.low()
        time.sleep_ms(10)
        self._SPIRST.high()
        time.sleep_ms(10)
        print_debug ("LCD Hard Reset End")

    def soft_reset(self): #Soft reset display
        print_debug("Soft reset start")
        self.write_command(GC9A01_SWRESET)
        delay(150)
        print_debug("Soft reset end")

#===================================================================================================
#MAIN PROGRAM ======================================================================================
#===================================================================================================

def main():
    print_debug("** Main Start **")
    tft = GC9A01()
    print_debug("** Main end **")

main()

Thank you for your help !

Topic		Replies	Views
DIsplay to Nicla Vision Arduino Boards	17	283	May 6, 2025
SPI crash on the Arduino Nicla Vision Arduino Boards	4	430	September 21, 2022
Connecting SPI display to Arduino Nicla vision library Arduino Boards	3	463	March 9, 2023
SD card module on Nicla Vision OpenMV Boards	3	42	November 8, 2024
Nicla Vision and additional GPIO Arduino Boards	1	1770	June 18, 2023

Nicla Vision, LCD GC9A01 and delay crash

Related topics