Fruit Jam -- OnDiskFont() fails with a "MemoryError: memory allocation failed, allocating 0 bytes" error

[ukscone]

CircuitPython version and board name

Adafruit CircuitPython 10.0.0-beta.2 on 2025-07-30; Adafruit Fruit Jam with rp2350b

Code/REPL

# SPDX-FileCopyrightText: Copyright (c) 2025 Tim C for Adafruit Industries
# SPDX-FileCopyrightText: Copyright (c) 2025 Anne Barela for Adafruit Industries
#
# SPDX-License-Identifier: MIT
#
import gc

from terminalio import Terminal
import displayio 
from lvfontio import OnDiskFont
from adafruit_fruitjam.peripherals import request_display_config
import supervisor

def draw_box(width, height, color_box, x, y):
#    top_left = '\xDA'  # CP437 characters for single line drawing
#    horizontal = '\xC4'
#    top_right = '\xBF'
#    vertical = '\xB3'
#    bottom_left = '\xC0'
#    bottom_right = '\xD9'
    top_left = '+'  # ASCII characters if the CP437 characters aren't working
    horizontal = '-'
    top_right = '+'
    vertical = '|'
    bottom_left = '+'
    bottom_right = '+'
    if width < 3 or height < 3:
        return
    goto(x, y)
    terminal.write(top_left + horizontal*(width - 2) + top_right+"\x1BD")
    for i in range(height):
        goto(x+i+1, y)
        terminal.write(vertical + ' '*(width - 2) + vertical+"\x1BD")
    goto(x+height, y)
    terminal.write(bottom_left+horizontal*(width - 2)+bottom_right+"\x1BD") 
  
def goto(x, y):
    seq = "\x1B[" + str(int(x)) + ";" + str(int(y)) + "H"
    terminal.write(seq)

# Use the easy library call to set the resolution

colors = 2

request_display_config(640, 480)

print(f"\nFree before display init: {gc.mem_free()}")

# Initialize display

main_group = displayio.Group()
display = supervisor.runtime.display
display.root_group = main_group

print(f"free: {gc.mem_free()}")

font = OnDiskFont("fonts/CamputersLynxAlt.bin")  # LVGL .bin font

char_size = font.get_bounding_box()
print(f"Character size: {char_size}")
screen_size = (display.width // char_size[0], display.height // char_size[1])
print(f"Screen size: {screen_size}")

terminal_palette = displayio.Palette(colors)
terminal_palette[0] = 0x000000
terminal_palette[1] = 0xffffff

print(f"Free after palette: {gc.mem_free()}")

term_bitmap = displayio.Bitmap(screen_size[0] * char_size[0], 
                               screen_size[1] * char_size[1], colors)
print(f"Free after bitmap: {gc.mem_free()}")   

terminal_area = displayio.TileGrid(
    bitmap=font.bitmap,
    width=screen_size[0],
    height=screen_size[1],
    tile_width=char_size[0],
    tile_height=char_size[1],
    pixel_shader=terminal_palette,
)
main_group.append(terminal_area)

print("About to create Terminal")
terminal = Terminal(terminal_area, font)
print("Created Terminal")
message = " Hello World\n This is LVGL text\r\n"
terminal.write(message)
print("Wrote message, now do a box")
terminal.write("\x1B[r")  # Set to whole screen (ineffective)
draw_box(10, 8, 1, 10, 25)

print("Done, infinite loop")
while True:
    pass

Behavior

%Run -c $EDITOR_CONTENT

Free before display init: 8093152
free: 8092928
Traceback (most recent call last):
File "", line 57, in
MemoryError: memory allocation failed, allocating 0 bytes

Description

Fairly regularly (60 times out of 100) both with the above code and with a modded https://learn.adafruit.com/fruit-jam-irc-client-in-circuitpython?view=all OnDiskFont() will fail with the above error message on the fonts noted in the additional information section. the lvgl bin fonts CamputersLynxStd & CamputersLynxAlt were created from the ttf files using https://lvgl.io/tools/fontconverter with the settings size 10, bpp 1, no fallback, output binary, range 0x20-0x7F. Sometimes the CamputersLynxAlt font produces a "missing glyph" error

The memory allocation error happens whether the Fruit Jam is freshly powered, after reset and in thonny repl. I fully expect that the fonts are corrupted somehow but it does seem regularly random

Additional information

I have uploaded the problematic lvgl converted ttf's and bins to https://eightgrubs.com/Files/

[tannewt]

Please try editing code.py directly instead of using Thonny. It plays weird tricks to run files.

[ukscone]

it happens when running from fruit jam power on with thonny not running. doesn't happen every time but just did a set of 10 power on, see what happens, power off.... and 4 out of the 10 times errored with the code.py line 40 memory allocation failed error. this is with the font used in the irc client mentioned above with the code.py that i added the onDiskFont() and the fonts to

# SPDX-License-Identifier: MIT
from os import getenv
from displayio import Group
from terminalio import FONT
import supervisor
import audiocore
import board
import busio
from digitalio import DigitalInOut
from adafruit_esp32spi import adafruit_esp32spi
from adafruit_color_terminal import ColorTerminal
from adafruit_fruitjam.peripherals import Peripherals
from adafruit_fruitjam.peripherals import request_display_config

from lvfontio import OnDiskFont

import gc


from curses_irc_client import run_irc_client

# Configuration - modify these values as needed
IRC_CONFIG = {
    "server": "irc.libera.chat",  # Example: irc.libera.chat, irc.freenode.net
    # "port": 6667,  # 6667 - clear text
    "port": 6697,  # 6697 - TLS encrypted
    "username": "ukscone",
    "channel": "#adafruit-fruit-jam",
}

if IRC_CONFIG["username"] == "":
    raise ValueError("username must be set in IRC_CONFIG")

main_group = Group()
request_display_config(720,400)
display = supervisor.runtime.display
print(f"free: {gc.mem_free()}")

font = OnDiskFont("/fonts/CamputersLynxStd.bin")  # LVGL .bin font
print(f"free: {gc.mem_free()}")

char_size = font.get_bounding_box()
print(f"Character size: {char_size}")
print(f"font.bitmap info: {font.bitmap.width}, {font.bitmap.height}")


font_bb = font.get_bounding_box()
screen_size = (display.width // font_bb[0], display.height // font_bb[1])

terminal = ColorTerminal(font, screen_size[0], screen_size[1])
main_group.append(terminal.tilegrid)
display.root_group = main_group

# Get WiFi details and Adafruit IO keys, ensure these are setup in settings.toml
# (visit io.adafruit.com if you need to create an account, or if you need your Adafruit IO key.)
ssid = getenv("CIRCUITPY_WIFI_SSID")
password = getenv("CIRCUITPY_WIFI_PASSWORD")

# If you are using a board with pre-defined ESP32 Pins:
esp32_cs = DigitalInOut(board.ESP_CS)
esp32_ready = DigitalInOut(board.ESP_BUSY)
esp32_reset = DigitalInOut(board.ESP_RESET)

spi = busio.SPI(board.SCK, board.MOSI, board.MISO)
esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset)

print("Connecting to AP...")
while not esp.is_connected:
    try:
        esp.connect_AP(ssid, password)
    except RuntimeError as e:
        print("could not connect to AP, retrying: ", e)
        continue

print("IRC Configuration:")
print(f"Server: {IRC_CONFIG['server']}:{IRC_CONFIG['port']}")
print(f"Nickname: {IRC_CONFIG['username']}")
print(f"Channel: {IRC_CONFIG['channel']}")
print("-" * 40)

fruit_jam_peripherals = Peripherals()
beep_wave = audiocore.WaveFile("beep.wav")
run_irc_client(
    esp,
    IRC_CONFIG,
    terminal,
    terminal.tilegrid,
    audio_interface=fruit_jam_peripherals.audio,
    beep_wave=beep_wave,
)

[TheKitty]

I can verify this behavior. I was running my terminal text program with a CP437 font. First time the code runs it errors as above. If I reran the code it worked fine. I was using Mu. I would have reported sooner, I thought it was part of the memory allocation issue being worked on before.

[tannewt]

Can you reproduce it without any wifi code? It's tricky to debug something that happens sometimes. wifi adds a lot of variability.

The memory fix I did recently is in beta.2 so I wouldn't expect absolute newest to be any different.

[ukscone]

the code at the top of this issue by Anne Barela also does it. Sometimes works, sometimes errors with memory allocation error