[Solved] Raspberry Pi 3B running ST7735 display

eifpaz · 6 April 2023 16:13

Hi again

Sorry for the delay, i’ve done a complete new install but still can’t get anything to work.
I now have the error : error: I2C device not found on address: 0x3C
I have tried using i2cdect but using 1 gives me nothing and using 0 gives me no such file.

I have also confused myself as to what pins I should be using on the GPIO. I have used https://luma-lcd.readthedocs.io/en/latest/hardware.html but they have potentially 2 different ones (SPI & Parallel) I have tried both but still nothing.

I’m sure I’m doing something really stupid.

Thanks again Eifion

eifpaz · 24 April 2023 14:45

Hi again

Sorry to be a pain. I have redone the install many times, read and re-read the install instructions and have finally worked out what is wrong.

By default, all the examples will assume I2C port 1, address 0x3C and the ssd1306 driver. If you need to use a different setting, these can be specified on the command line – each program can be invoked with a --help flag to show the options:

Now no matter how many times I read this, I cannot work out how to set the default to SPI.

Can anyone please help and explain how to do this?

Thanks all
Eifion

Jappe · 24 April 2023 16:36

As you already said correctly, you can specify this on the CLI when starting the demos, like shown on their github page:
https://github.com/rm-hull/luma.examples

I2C:
  --i2c-port I2C_PORT   I2C bus number (default: 1)
  --i2c-address I2C_ADDRESS
                        I2C display address (default: 0x3C)

SPI:
  --spi-port SPI_PORT   SPI port number (default: 0)
  --spi-device SPI_DEVICE
                        SPI device (default: 0)
  --spi-bus-speed SPI_BUS_SPEED
                        SPI max bus speed (Hz) (default: 8000000)
  --spi-transfer-size SPI_TRANSFER_SIZE
                        SPI bus max transfer unit (bytes) (default: 4096)
  --spi-cs-high SPI_CS_HIGH
                        SPI chip select is high (gpio_cs_spi driver only)
                        (default: False)

 --interface INTERFACE, -i INTERFACE
                        Interface type. Allowed values are: i2c, noop, spi,
                        gpio_cs_spi, bitbang, ftdi_spi, ftdi_i2c, pcf8574,
                        bitbang_6800 (default: i2c)

python3 demo.py -i spi should set it to SPI.

Dunno if this was answered/asked before, but did you activate SPI and I2C with dietpi-config?

eifpaz · 25 April 2023 16:13

After Googling CLI followed by a lot of head scratching and coffee, I have the examples running, so thank you so much @Jappe but no doubt I will be back.

Thanks again to you both.

Joulinar · 25 April 2023 16:35

CLI = command line interface = SSH access = direct shell access

eifpaz · 26 April 2023 11:39

@Joulinar yep got it now thanks. I’m learning very slowly

Joulinar · 26 April 2023 14:49

even a small learning curve, is a learning curve

eifpaz · 28 April 2023 14:59

Sorry guys, I have been running the examples fine, but when I try to run stats I get the following;

eif@raspberrypi:~/luma.examples/examples $ python3 stats.py -i spi -d st7735 --w                                                idth 160 --height 128 -r2
Version: luma.lcd 2.10.0 (luma.core 2.4.0)
Display: st7735
Interface: spi
Dimensions: 160 x 128
------------------------------------------------------------
Traceback (most recent call last):
  File "/home/eif/luma.examples/examples/stats.py", line 143, in <module>
    main()
  File "/home/eif/luma.examples/examples/stats.py", line 136, in main
    stats(device)
  File "/home/eif/luma.examples/examples/stats.py", line 114, in stats
    font2 = ImageFont.truetype(font_path, 16)
  File "/usr/local/lib/python3.9/dist-packages/PIL/ImageFont.py", line 996, in t                                                ruetype
    return freetype(font)
  File "/usr/local/lib/python3.9/dist-packages/PIL/ImageFont.py", line 993, in f                                                reetype
    return FreeTypeFont(font, size, index, encoding, layout_engine)
  File "/usr/local/lib/python3.9/dist-packages/PIL/ImageFont.py", line 248, in _                                                _init__
    self.font = core.getfont(
OSError: cannot open resource

Any ideas please?

Thanks

AgentX · 28 April 2023 15:23

Try to copy the stats.py to inside the examples folder.

eifpaz · 28 April 2023 15:29

@AgentX already tried that, but still the same unfortunately

AgentX · 28 April 2023 15:50

In the stats.py it requires ‘PixelOperator.ttf’ :

# use custom font
    font_path = os.path.abspath(os.path.join(os.path.dirname(__file__), 'fonts', 'PixelOperator.ttf'))
    font2 = ImageFont.truetype(font_path, 16)

That font is not included in the original examples folder, get it from GitHub or something and place it inside (adjust the path as needed):

/home/quake3/luma.examples/examples/fonts

And in your line:

eif@raspberrypi:~/luma.examples/examples $ python3 stats.py -i spi -d st7735 --w idth 160 --height 128 -r2

You don’t need to set the Width and Height because there’s a config file for each screen inside:

/home/quake3/luma.examples/conf

This is the line I use in sudo crontab -e :

@reboot python3 /home/quake3/LCD-Stats/examples/stats.py --config /home/quake3/LCD-Stats/conf/st7735mod.conf &

eifpaz · 29 April 2023 11:04

You Sir are a star, all working.

AgentX · 4 July 2023 05:54

Hi,

I updated my DietPi from Bullseye to Bookworm and my ST7735 display stopped working.

I decided to do a fresh install of DietPi Bookworm.

But as soon as I try to install the “luma.lcd” library it outputs the following errors:

sudo -H pipx install luma.lcd
Fatal error from pip prevented installation. Full pip output in file:
    /root/.local/pipx/logs/cmd_2023-07-04_06.44.19_pip_errors.log

pip failed to build packages:
    RPI.GPIO
    spidev

Some possibly relevant errors from pip install:
    error: subprocess-exited-with-error
    source/common.c:23:10: fatal error: Python.h: No such file or directory
    error: command '/usr/bin/aarch64-linux-gnu-gcc' failed with exit code 1
    spidev_module.c:28:10: fatal error: Python.h: No such file or directory

Error installing luma-lcd.

I’m using “pipx” and not normal “pip” cause it was suggested by the output of the command:

sudo -H pip install --upgrade luma.lcd
error: externally-managed-environment

× This environment is externally managed
╰─> To install Python packages system-wide, try apt install
    python3-xyz, where xyz is the package you are trying to
    install.
    
    If you wish to install a non-Debian-packaged Python package,
    create a virtual environment using python3 -m venv path/to/venv.
    Then use path/to/venv/bin/python and path/to/venv/bin/pip. Make
    sure you have python3-full installed.
    
    If you wish to install a non-Debian packaged Python application,
    it may be easiest to use pipx install xyz, which will manage a
    virtual environment for you. Make sure you have pipx installed.
    
    See /usr/share/doc/python3.11/README.venv for more information.

note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.

I have installed “RPI.GPIO” through “dietpi-software”, and can’t install “python3-spidev” due to different version.

I also installed “gcc”.

Can someone please help make this work again?

Joulinar · 4 July 2023 10:02

seems you are missing python module Python.h. You could try to install apt package libdlib-dev Debian -- Package Contents Search Results -- Python.h

AgentX · 4 July 2023 10:26

Thanks for your suggestion but it did not work.

It still outputs the same error:

sudo -H pipx install luma.lcd
Fatal error from pip prevented installation. Full pip output in file:
    /root/.local/pipx/logs/cmd_2023-07-04_11.23.47_pip_errors.log

pip failed to build packages:
    RPI.GPIO
    spidev

Some possibly relevant errors from pip install:
    error: subprocess-exited-with-error
    source/common.c:23:10: fatal error: Python.h: No such file or directory
    error: command '/usr/bin/aarch64-linux-gnu-gcc' failed with exit code 1
    spidev_module.c:28:10: fatal error: Python.h: No such file or directory

Error installing luma-lcd.

Joulinar · 5 July 2023 15:58

hm strange, did you reboot system in between?

@MichaIng any ideas?

MichaIng · 6 July 2023 19:39

Generally, install the whole Python development package suite to rule this out:

sudo apt install python3-dev

Should be however included with our Python 3 install option.

What about installing RPI.GPIO via APT package (globally)?

sudo apt install python3-rpi.gpio

We also have a dietpi-software install option for this.

AgentX · 7 July 2023 17:12

Hi,

Sorry for the late reply.

Your suggestion works, after I installed python3-dev I was able to install the luma.lcd library.

But had to run the command:

sudo -H pipx install luma.lcd --include-deps

And as soon as I run:

sudo python3 /home/server/LCD-Stats/examples/stats.py --config /home/server/LCD-Stats/conf/st7735mod.conf

It outputs the following error: > Traceback (most recent call last):

File “/home/server/LCD-Stats/examples/stats.py”, line 7, in
import psutil
ModuleNotFoundError: No module named ‘psutil’

When I run:

sudo -H pip install psutil

It outputs the following error: > error: externally-managed-environment

× This environment is externally managed
╰─> To install Python packages system-wide, try apt install
python3-xyz, where xyz is the package you are trying to
install.
If you wish to install a non-Debian-packaged Python package,
create a virtual environment using python3 -m venv path/to/venv.
Then use path/to/venv/bin/python and path/to/venv/bin/pip. Make
sure you have python3-full installed.

If you wish to install a non-Debian packaged Python application,
it may be easiest to use pipx install xyz, which will manage a
virtual environment for you. Make sure you have pipx installed.

See /usr/share/doc/python3.11/README.venv for more information.
note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.

And when I run:

sudo -H pipx install psutil

It outputs the following error:

No apps associated with package psutil or its dependencies. If you are attempting to install a library, pipx should not be used. Consider using pip or a similar tool instead.

I also tried:

sudo -H pipx install psutils

And it outputs the following error: > Fatal error from pip prevented installation. Full pip output in file:

/root/.local/pipx/logs/cmd_2023-07-07_18.03.16_pip_errors.log
Some possibly relevant errors from pip install:
ERROR: Could not find a version that satisfies the requirement psutils (from versions: none)
ERROR: No matching distribution found for psutils

I think I’m tired of beating a dead horse, Debian 12 gave me nothing but problems, I use Debian 12 as a desktop OS and had and still have some problems installing Lutris and games on it.