pico micropython MemoryError: memory allocation failed, allocating x bytes

[feiticeir0]

Hi all !
I've solved this problem by using the previous MicroPython version - [v1.20.0 (2023-04-26)] , but I'm posting it anyway.

With the new Pico-W MicroPython version - [v1.21.0 (2023-10-05) ], I'm trying to run a Waveshare Pico-ResTouchLCD 3.5 code and I get the following error:

pico micropython MemoryError: memory allocation failed, allocating 153600 bytes

With the previous version, no problem whatsoever.

Here's the code (from Waveshare Pico-ResToch-LCD-3.5):

from machine import Pin,SPI,PWM
import framebuf
import time
import os

LCD_DC   = 8
LCD_CS   = 9
LCD_SCK  = 10
LCD_MOSI = 11
LCD_MISO = 12
LCD_BL   = 13
LCD_RST  = 15
TP_CS    = 16
TP_IRQ   = 17

class LCD_3inch5(framebuf.FrameBuffer):

    def __init__(self):
        self.RED   =   0x07E0
        self.GREEN =   0x001f
        self.BLUE  =   0xf800
        self.WHITE =   0xffff
        self.BLACK =   0x0000
        
        self.width = 480
        self.height = 160
        
        self.cs = Pin(LCD_CS,Pin.OUT)
        self.rst = Pin(LCD_RST,Pin.OUT)
        self.dc = Pin(LCD_DC,Pin.OUT)
        
        self.tp_cs =Pin(TP_CS,Pin.OUT)
        self.irq = Pin(TP_IRQ,Pin.IN)
        
        self.cs(1)
        self.dc(1)
        self.rst(1)
        self.tp_cs(1)
        self.spi = SPI(1,60_000_000,sck=Pin(LCD_SCK),mosi=Pin(LCD_MOSI),miso=Pin(LCD_MISO))
              
        self.buffer = bytearray(self.height * self.width * 2)
        super().__init__(self.buffer, self.width, self.height, framebuf.RGB565)
        self.init_display()

        
    def write_cmd(self, cmd):
        self.cs(1)
        self.dc(0)
        self.cs(0)
        self.spi.write(bytearray([cmd]))
        self.cs(1)

    def write_data(self, buf):
        self.cs(1)
        self.dc(1)
        self.cs(0)
        #self.spi.write(bytearray([0X00]))
        self.spi.write(bytearray([buf]))
        self.cs(1)


    def init_display(self):
        """Initialize dispaly"""  
        self.rst(1)
        time.sleep_ms(5)
        self.rst(0)
        time.sleep_ms(10)
        self.rst(1)
        time.sleep_ms(5)
        self.write_cmd(0x21)
        self.write_cmd(0xC2)
        self.write_data(0x33)
        self.write_cmd(0XC5)
        self.write_data(0x00)
        self.write_data(0x1e)
        self.write_data(0x80)
        self.write_cmd(0xB1)
        self.write_data(0xB0)
        self.write_cmd(0x36)
        self.write_data(0x28)
        self.write_cmd(0XE0)
        self.write_data(0x00)
        self.write_data(0x13)
        self.write_data(0x18)
        self.write_data(0x04)
        self.write_data(0x0F)
        self.write_data(0x06)
        self.write_data(0x3a)
        self.write_data(0x56)
        self.write_data(0x4d)
        self.write_data(0x03)
        self.write_data(0x0a)
        self.write_data(0x06)
        self.write_data(0x30)
        self.write_data(0x3e)
        self.write_data(0x0f)
        self.write_cmd(0XE1)
        self.write_data(0x00)
        self.write_data(0x13)
        self.write_data(0x18)
        self.write_data(0x01)
        self.write_data(0x11)
        self.write_data(0x06)
        self.write_data(0x38)
        self.write_data(0x34)
        self.write_data(0x4d)
        self.write_data(0x06)
        self.write_data(0x0d)
        self.write_data(0x0b)
        self.write_data(0x31)
        self.write_data(0x37)
        self.write_data(0x0f)
        self.write_cmd(0X3A)
        self.write_data(0x55)
        self.write_cmd(0x11)
        time.sleep_ms(120)
        self.write_cmd(0x29)
        
        self.write_cmd(0xB6)
        self.write_data(0x00)
        self.write_data(0x62)
        
        self.write_cmd(0x36)
        self.write_data(0x28)
    def show_up(self):
        self.write_cmd(0x2A)
        self.write_data(0x00)
        self.write_data(0x00)
        self.write_data(0x01)
        self.write_data(0xdf)
        
        self.write_cmd(0x2B)
        self.write_data(0x00)
        self.write_data(0x00)
        self.write_data(0x00)
        self.write_data(0x9f)
        
        self.write_cmd(0x2C)
        
        self.cs(1)
        self.dc(1)
        self.cs(0)
        self.spi.write(self.buffer)
        self.cs(1)
    def show_down(self):
        self.write_cmd(0x2A)
        self.write_data(0x00)
        self.write_data(0x00)
        self.write_data(0x01)
        self.write_data(0xdf)
        
        self.write_cmd(0x2B)
        self.write_data(0x00)
        self.write_data(0xA0)
        self.write_data(0x01)
        self.write_data(0x3f)
        
        self.write_cmd(0x2C)
        
        self.cs(1)
        self.dc(1)
        self.cs(0)
        self.spi.write(self.buffer)
        self.cs(1)
    def bl_ctrl(self,duty):
        pwm = PWM(Pin(LCD_BL))
        pwm.freq(1000)
        if(duty>=100):
            pwm.duty_u16(65535)
        else:
            pwm.duty_u16(655*duty)
    def draw_point(self,x,y,color):
        self.write_cmd(0x2A)

        
        self.write_data((x-2)>>8)
        self.write_data((x-2)&0xff)
        self.write_data(x>>8)
        self.write_data(x&0xff)
        
        self.write_cmd(0x2B)
        self.write_data((y-2)>>8)
        self.write_data((y-2)&0xff)
        self.write_data(y>>8)
        self.write_data(y&0xff)
        
        self.write_cmd(0x2C)
        
        self.cs(1)
        self.dc(1)
        self.cs(0)
        for i in range(0,9):
            h_color = bytearray(color>>8)
            l_color = bytearray(color&0xff)
            self.spi.write(h_color)
            self.spi.write(l_color)
        self.cs(1)
    def touch_get(self): 
        if self.irq() == 0:
            self.spi = SPI(1,5_000_000,sck=Pin(LCD_SCK),mosi=Pin(LCD_MOSI),miso=Pin(LCD_MISO))
            self.tp_cs(0)
            X_Point = 0
            Y_Point = 0
            for i in range(0,3):
                self.spi.write(bytearray([0XD0]))
                Read_date = self.spi.read(2)
                time.sleep_us(10)
                X_Point=X_Point+(((Read_date[0]<<8)+Read_date[1])>>3)
                
                self.spi.write(bytearray([0X90]))
                Read_date = self.spi.read(2)
                Y_Point=Y_Point+(((Read_date[0]<<8)+Read_date[1])>>3)

            X_Point=X_Point/3
            Y_Point=Y_Point/3
            
            self.tp_cs(1) 
            self.spi = SPI(1,60_000_000,sck=Pin(LCD_SCK),mosi=Pin(LCD_MOSI),miso=Pin(LCD_MISO))
            Result_list = [X_Point,Y_Point]
            #print(Result_list)
            return(Result_list)
if __name__=='__main__':

    LCD = LCD_3inch5()
    LCD.bl_ctrl(100)
    #color BRG
    LCD.fill(LCD.WHITE)
    LCD.fill_rect(140,5,200,30,LCD.RED)
    LCD.text("Raspberry Pi Pico",170,17,LCD.WHITE)
    display_color = 0x001F
    LCD.text("3.5' IPS LCD TEST",170,57,LCD.BLACK)
    for i in range(0,12):      
        LCD.fill_rect(i*30+60,100,30,50,(display_color))
        display_color = display_color << 1
    LCD.show_up()
    
    while True:      
        get = LCD.touch_get()
        if get != None: 
            X_Point = int((get[1]-430)*480/3270)
            if(X_Point>480):
                X_Point = 480
            elif X_Point<0:
                X_Point = 0
            Y_Point = 320-int((get[0]-430)*320/3270)
            if(Y_Point>220):
                LCD.fill(LCD.WHITE)
                if(X_Point<120):
                    LCD.fill_rect(0,60,120,100,LCD.RED)
                    LCD.text("Button0",20,110,LCD.WHITE)
                elif(X_Point<240):
                    LCD.fill_rect(120,60,120,100,LCD.RED)
                    LCD.text("Button1",150,110,LCD.WHITE)
                elif(X_Point<360):
                    LCD.fill_rect(240,60,120,100,LCD.RED)
                    LCD.text("Button2",270,110,LCD.WHITE)
                else:
                    LCD.fill_rect(360,60,120,100,LCD.RED)
                    LCD.text("Button3",400,110,LCD.WHITE)           
        else :
           LCD.fill(LCD.WHITE)
           LCD.text("Button0",20,110,LCD.BLACK)
           LCD.text("Button1",150,110,LCD.BLACK)
           LCD.text("Button2",270,110,LCD.BLACK)
           LCD.text("Button3",400,110,LCD.BLACK)
        
        LCD.show_down()  
        time.sleep(0.1)

Thank you

[feiticeir0]

I've closed this because It's a problem that I was able to replicate also with the previous version - the one I was running .
If I run a previous sketch - just blinking a LED and then try to run this sketch, I get the same error...

from machine import Pin
from time import sleep

led = Pin('LED', Pin.OUT)
print ('Blinking')

while True:
    led.value(not led.value())
    sleep(0.5)

Don't know why...
Thank you and sorry for bother you.

[jimmo]

@feiticeir0 Can you confirm what you mean here -- are you saying that the above 7-line snippet blinking the LED causes the same MemoryError: memory allocation failed, allocating 153600 bytes error?

[feiticeir0]

Hi @jimmo . That's true. Still don't understand why. I've already used this screen before, with the previous MicroPython version (not with the PICO W, but the one without WiFi), and never had a problem. I don't know if start using VScode for MicroPython with the Micropico extension had anything to do with it.
I've closed the issue because I think this has nothing to do with MicroPython. Will do more tests on the coming weeks, and will reopen this if necessary.
Thank you

[peterhinch]

The line

self.buffer = bytearray(self.height * self.width * 2)

allocates exactly 153,600 bytes. This is a huge requirement for contiguous RAM and is only likely to succeed if performed very early, prior to other allocations.

You might like to look at this doc for a driver form the 320*480 Pico Res Touch. The driver uses 4-bit pixels via a lookup table to get the driver down to a manageable size.

[AlmightyOatmeal]

I have been modifying micro-gui code to run on a ESP32 WROOM and noticed I was running into a similar error and I noticed that I had to move some of the imports further down the code while running a garbage collection, I'm then left with 43k of available memory. OP may want to try garbage collection prior to the byte array.

I'm also using a much smaller buffer buf = bytearray(height * width // 2)

For example, this code works:

from machine import Pin, SPI, freq
import gc
from gui.ili94xx.ili9486 import ILI9486 as SSD

pdc = Pin(17, Pin.OUT, value=0)
prst = Pin(16, Pin.OUT, value=1)
pcs = Pin(5, Pin.OUT, value=1)
spi = SPI(1, sck=Pin(18), mosi=Pin(23), miso=Pin(19), baudrate=32_000_000)
gc.collect()
ssd = SSD(spi, pcs, pdc, prst)

from gui.core.ugui import Display

...

display = Display(ssd, nxt, sel, prev, increase, decrease)

ssd.fill(0)

from gui.core import colors

display.rect(x1=10, y1=70, w=100, h=50, color=colors.BLUE)

ssd.show()

Where-as this did not:

from machine import Pin, SPI, freq
import gc
from gui.ili94xx.ili9486 import ILI9486 as SSD
from gui.core.ugui import Display
from gui.core import colors

pdc = Pin(17, Pin.OUT, value=0)
prst = Pin(16, Pin.OUT, value=1)
pcs = Pin(5, Pin.OUT, value=1)
spi = SPI(1, sck=Pin(18), mosi=Pin(23), miso=Pin(19), baudrate=32_000_000)
gc.collect()
ssd = SSD(spi, pcs, pdc, prst)

...

display = Display(ssd, nxt, sel, prev, increase, decrease)

ssd.fill(0)

display.rect(x1=10, y1=70, w=100, h=50, color=colors.BLUE)

ssd.show()

I'm going to continue working on the micro gui and driver to see what kind of functionality I can get out of it within the limited footprint of this particular esp32 but so far it's looking promising!

[peterhinch]

I have reopened this because in my view the RAM requirement of this Waveshare driver are excessive for its intended host. Users wishing to use this display with MicroPython should be prepared to adapt the driver to use a smaller buffer.

[feiticeir0]

Thank you @peterhinch . Will try that driver you pointed out. It looks great.
Could this be an issue with only the Pico W ? I've been using this one with a Pico without any issues...
Thank you

[peterhinch]

The Pico W has less free RAM - about 173K vs 222K. Trying to allocate a 153,600 byte buffer on a Pico W is, er, ambitious.

I think a general warning is in order here. In my opinion software published by Waveshare is of variable quality. Caveat emptor applies.

Note that the driver I referenced has not been tested on your display and will need some adaptation.

[feiticeir0]

I've opened a ticket with waveshare and their answer was that the Pico-ResTouch-LCD-3.5 does not work with the Pico W.
They have great products, but the support lacks sometimes..
Thank you.