Available RAM of Guition JC8048W550N board with ESP32S3 FH16R8 seems to be very low

[rzuehlsd]

First I would like to thank you for this incredible piece of work! It helped me to create an image for my JC8048W550N board without touch panel.

Build was very smooth, but after I flashed and started the device, I discovered that compared to a standard MicroPython image which supports PSRAM I am short of about 2.6MB RAM.

Are these memory chunks pre allocated for the lvgl drivers and therefore not available or am I missing a specific build configuration?

I would be very glad to get a hint about this topic.

• How I build the image

I used the toml approach to create the image and after some small adjustments in the template in display_configs for this board I was able to compile and build the image with:

python3 make.py --toml=myBoards/JC8048W550N/JC8048W550N.toml

with the following toml file:

####################################################################
#
#       Config File for Guition JC8048W550N withou touch panel
#       ESP32S3 FH16R8  16MB Flash and 8MB PSRAM
#                       RZ, 18.07.2025
#
#       Changes to template in 'custom_board_and_toml_examples':
#       -   All entries for configuration of gt911 touch panel have been commented out!
#       -   RGBBus frequency set to 12MHz from previous 16MHz
#####################################################################


[MCU.esp32]
BOARD = "ESP32_GENERIC_S3"
BOARD_VARIANT = "SPIRAM_OCT"
flash_size = 16
enable_jtag_repl = 'n'
enable_cdc_repl = 'n'
enable_uart_repl = 'y'
uart_repl_bitrate = 115200


[RGBBus.display_bus]
data0 = 8
data1 = 3
data2 = 46
data3 = 9
data4 = 1
data5 = 5
data6 = 6
data7 = 7
data8 = 15
data9 = 16
data10 = 4
data11 = 45
data12 = 48
data13 = 47
data14 = 21
data15 = 14
hsync = 39
vsync = 41
de = 40
pclk = 42
freq = 12000000             # recommendation of kdschlosser
hsync_front_porch = 8
hsync_back_porch = 8
hsync_pulse_width = 4
hsync_idle_low = false
vsync_front_porch = 8
vsync_back_porch = 8
vsync_pulse_width = 4
vsync_idle_low = false
de_idle_high = false
pclk_idle_high = false
pclk_active_low = true


[I2C.Bus.i2c_bus]
host = 0
scl = 20
sda = 19
freq = 400000



[RGBDisplay.display]
data_bus = "display_bus"
display_width = 800
display_height = 480
backlight_pin = 2
color_space = "lv.COLOR_FORMAT.RGB565"


[display.set_power]
params = [true]


[display.init]
params = []

# JC8048W550N has no touch panel
#
# [I2C.Device.indev_device]
# bus = "i2c_bus"
# dev_id = "gt911.I2C_ADDR"
# reg_bits = "gt911.BITS"
#
# [gt911.indev]
# device = "indev_device"
#
# [indev.firmware_config.fw_config]
# width.value = 800
# height.value = 480
# save.params = []



[display.set_backlight]
params = [100]


[task_handler.TaskHandler]
params=[]

• How I tested the image

After flashing my board with the new image I started the board in Thommy and within my boot script looked at the provided memory and got the following output:

MCU Parameter:
CPU Freq:    240.0 MHz
Free RAM:  5697.06 kB
Flash:       16777.22 kB
MCU Temp:    32 C
Extended SPIRAM is supported!

Virtual File System Usage:
Total space: 14135.3 kB
Free space:  14118.91 kB ( 99.88409 %)

So SPIRAM is supported but compared to the 8.3MB I have available within the standard MicroPython image with octal PSRAM I am short of 2.6MB RAM.

I tested the lvgl support with the following very simple program:

import lvgl as lv
import display


# Create a button with a label
scr = lv.obj()
btn = lv.button(scr)
btn.align(lv.ALIGN.CENTER, 0, 0)
label = lv.label(btn)
label.set_text('Hello World!')
lv.screen_load(scr)

It worked out of the box, but I also noted that the program crashes after a soft reset of the device. No problems after hard reset of the board.

• Modifications to the templates in display_configs

By the way the section [indev.firmware_config.fw_config] had to be changed from the definitions provided in the template to make the build process working. This incompatible section in the toml templates could also be found in 'ESP32-S3-Touch-LCD-4.3.toml', 'CYD-8048S070C.toml', 'CYD-8048S043C.toml', 'CYD-3248S035C.toml' and 'CYD-2432S032C.toml'.

Chad to change

[indev.firmware_config.fw_config]

[fw_config.width]
value=800

[fw_config.height]
value=480

[fw_config.save]
params=[]

to

[indev.firmware_config.fw_config]
width.value = 800
height.value = 480
save.params = []

After this small modifications everything worked very smoothly.

Again many thanks for this great piece of work.

[rzuehlsd]

Short correction:

RGBBus frequency has to be 16MHz. With 12MHz only a white screen is shown.

[kdschlosser]

it is short the memory because the instructions that drive the display need to be placed into SPIRAM in order for the display to be able to run at the 16mHz. Some RGB displays will not operate at a lower frequency that the 16mHz and in order to get the increase in speed to achieve that instructions need to be moved from flash to SPIRAM where they are able to be executed at twice the speed. This would not need to be done if the MCU that was used had octal flash. It is the way it has to be to get things to work properly.

You can try turning the option off that does this by adding CONFIG_SPIRAM_XIP_FROM_PSRAM=n to your build command. You would need to lower the clock on the display down to the 12mHz to 13mHz area when you do that. If it works you will see a UI displayed and if not you won't. But if you test the amount of available memory you will see that the 2mb+ is no longer being used.

[kdschlosser]

the soft reset crash is something I am working on fixing. It has to deal with the MicroPython GC and LVGL objects not being garbage collected when lv_deinit is called.

[rzuehlsd]

Thanks for the clarification. I tried with lower frequencies but no success.

[kdschlosser]

You would need to add CONFIG_SPIRAM_XIP_FROM_PSRAM=n to your build command and then mess about with the frequencies to see if the display will run at slower speeds.