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Tag: python

Case + OLED display for Raspberry Pi with status panel

I was tempted to just switch cases from my Raspberry Pi 4 to the Raspberry Pi 5, but look at it…

  • 16×2 LCD display from an Arduino Starter Kit
  • C++ program with the WiringPi library
  • DIY case

I was really proud of it at the time and it was good learning back in 2020, but surely I could do better. Surely I could do a cool status panel!!

Components

  • Raspberry Pi (probably compatible with any of them)
  • OLED display (RGB 1.5 inch size is ideal)
  • PCB prototype board
  • Jumper cables
  • Soldering iron
(courtesy of epiCRealism model in ComfyUI)
  • Casing (3D printed or handcrafted)

Software config

I'll configure the Raspberry to interact with this display using python, with the Adafruit Circuitpython library for the SSD1351 display controller:
https://learn.adafruit.com/adafruit-1-5-color-oled-breakout-board/python-wiring-and-setup#setup-3042417

It's as simple as installing Circuitpython with the following command:

sudo pip3 install --upgrade click setuptools adafruit-python-shell build adafruit-circuitpython-rgb-display

If you find issues with your python version not finding a compatible circuit python version, include --break-system-packages at the end. (It wont break anything today, but don't get used to it...)

sudo pip3 install --upgrade click setuptools adafruit-python-shell build adafruit-circuitpython-rgb-display --break-system-packages

Wiring

Now wire your display according to the manufacturer guidance. Mine is this one from BuyDisplay:

https://www.buydisplay.com/full-color-1-5-inch-arduino-raspberry-pi-oled-display-module-128x128

OLED DisplayRaspberry Pi (pin #)
GNDGND (20)
VCC3V3 (17)
SCLSPI0 SCLK (23)
SDASPI0 MOSI (19)
RESGPIO25 (22)
DCGPIO 24 (18)
CSSPI0 CE0 (24)

Use a site like pinout.xyz to find a suitable wiring configuration.

You're ready to do some tests before making your final move to the PCB.

Script config

You can try Adafruit's demo script. Just make sure that you choose the right display and update any changes to the ping assignment (use IO numbers/names rather than physical pin numbers):

# Configuration for CS and DC pins (adjust to your wiring):
cs_pin = digitalio.DigitalInOut(board.CE0)
dc_pin = digitalio.DigitalInOut(board.D24)
reset_pin = digitalio.DigitalInOut(board.D25)

# Setup SPI bus using hardware SPI:
spi = board.SPI()

disp = ssd1351.SSD1351(spi, rotation=270,                         # 1.5" SSD1351
    cs=cs_pin,
    dc=dc_pin,
    rst=reset_pin,
    baudrate=BAUDRATE
)

Assembly

Here are the STL 3D files for this case design:

Now let's put it all together:

  1. Screw the frame to the display
  2. Solder the 7 pins of the display to 7 jumper cables across the PCB
  3. Wire all connections to the Raspberry Pi
  4. Screw the top and bottom pieces together
  5. Place the display on the support

Final result

I've shared the script you see on the images via github:

https://github.com/TheRoam/RaspberryPi-SSD1351-OLED

It currently displays:

  • Time and date
  • System stats (OS, disk usage and CPU temperature)
  • Local weather from World Meteorological Organization (updated hourly)

And this is how it ends up looking. Much better right?

As always, enjoy your tinkering, and let me know any comments or issues on Twitter!

🐦 @RoamingWorkshop

UNIHIKER-PAL: open-source python home assistant simplified

PAL is a simplified version of my python home assistant that I’m running in the DFRobot UNIHIKER which I’m releasing as free open-source.

This is just a demonstration for voice-recognition command-triggering simplicity using python and hopefully will serve as a guide for your own assistant.

Current version: v0.1.0

Features

Current version includes the following:

  • Voice recognition: using open-source SpeechRecognition python library, returns an array of all the recognised audio strings.
  • Weather forecast: using World Meteorological Organization API data, provides today's weather and the forecast for the 3 coming days. Includes WMO weather icons.
  • Local temperature: reads local BMP-280 temperature sensor to provide a room temperature indicator.
  • IoT HTTP commands: basic workflow to control IoT smart home devices using HTTP commands. Currently turns ON and OFF a Shelly2.5 smart switch.
  • Power-save mode: controls brightness to lower power consumption.
  • Connection manager: regularly checks wifi and pings to the internet to restore connection when it's lost.
  • PAL voice samples: cloned voice of PAL from "The Mitchells vs. The Machines" using the AI voice model CoquiAI-TTS v2.
  • UNIHIKER buttons: button A enables a simple menu (this is thought to enable a more complex menu in the future).
  • Touchscreen controls: restore brightness (center), switch program (left) and close program (right), when touching different areas of the screen.

Installation

  1. Install dependencies for voice recognition:
    pip install SpeechRecognition
  2. Download the github repo:
    https://github.com/TheRoam/UNIHIKER-PAL
  3. Upload the files and folders to the UNIHIKER in /root/upload/PAL/
  4. Configure in the script the WIFI credentials, IoT devices, theme, etc.
  5. Run the python script PAL_v010.py from the Mind+ terminal or from the UNIHIKER touch interface.

If you enable Auto boot from the Service Toggle menu , the script will run every time the UNIHIKER is restarted.

https://www.unihiker.com/wiki/faq#Error:%20python3:%20can't%20open%20file…

Configuration

The code includes different configurable aspects:

Theme

Some theme configuration has been enabled by allowing to choose between different eyes as a background image.

Use the variables "eyesA" and "eyesB" specify one of the following values to change the background image expression of PAL:

  • "happy"
  • "angry"
  • "surprised"
  • "sad"

"eyesA" is used as the default background and "eyesB" will be used as a transition when voice recognition is activated and PAL is talking.

The default value for "eyesA" is "surprised" and it will change to "happy" when a command is recognized.

PAL voice

Use the sample audio file "PAL_full" below (also in the github repo in /mp3) as a reference audio for CoquiAI-TTS v2 voice cloning and produce your personalized voices:

https://huggingface.co/spaces/coqui/xtts

Customizable commands

Adding your own commands to PAL is simple using the "comandos" function.

Every audio recognized by SpeechRecognition is sent as a string to the "comandos" function, which then filters the content and triggers one or another matching command.

Just define all the possible strings that could be recognized to trigger your command (note that sometimes SpeechRecognition provides wrong or inaccurate transcriptions).

Then define the command that is triggered if the string is matched.

def comandos(msg):
    # LAMP ON
    if any(keyword in msg for keyword in ["turn on the lamp", "turn the lights on","turn the light on", "turn on the light", "turn on the lights"]):
        turnLAMP("on")
        os.system("aplay '/root/upload/PAL/mp3/Turn_ON_lights.wav'")

Activation keyword

You can customize the keywords or strings that will activate command functions. If any of the keywords in the list is recognized, the whole sentence is sent to the "comandos" function to find any specific command to be triggered.

For the case of PAL v0.1, these are the keywords that activate it (90% it's Paypal):

activate=[
    "hey pal",
    "hey PAL",
    "pal",
    "pall",
    "Pall",
    "hey Pall",
    "Paul",
    "hey Paul",
    "pol",
    "Pol",
    "hey Pol",
    "poll",
    "pause",
    "paypal",
    "PayPal",
    "hey paypal",
    "hey PayPal"
]

You can change this to any other sentence or name, so PAL is activated when you call it by these strings.

Location

The variable "CityID" is used by the WMO API to provide more accurate weather forecast for your location.

Choose one of the available locations from the official list:

https://worldweather.wmo.int/en/json/full_city_list.txt

IoT devices

At the moment, PAL v0.1.0 only includes compatibility with Shelly2.5 for demonstration purposes.

Use variables lampBrand, lampChannel and lampIP to suit your Shelly2.5 configuration.

This is just as an example to show how different devices could be configured. These variables should be used to change the particularities of the HTTP command that is sent to different IoT devices.

More devices will be added in future releases, like Shelly1, ShellyDimmer, Sonoff D1, etc.

Power save mode

Power saving reduces the brightness of the device in order to reduce the power consumption of the UNIHIKER. This is done using the system command "brightness".

Change "ps_mode" variable to enable ("1") or disable ("0") the power-save mode.

Room temperature

Change "room_temp" variable to enable ("1") or disable ("0") the local temperature reading module. This requires a BMP-280 sensor to be installed using the I2C connector.

Check this other post for details on sensor installation:

https://theroamingworkshop.cloud/b/en/2490/

Demo

Below are a few examples of queries and replies from PAL:

"Hey PAL, turn on the lights!"
"Hey PAL, turn the lights off"

Future releases (To-Do list)

I will be developing these features in my personal assistant, and will be updating the open-source release every now and then. Get in touch via github if you have special interest in any of them:

  • Advanced menu: allow configuration and manually triggering commands.
  • IoT devices: include all Shelly and Sonoff HTTP API commands.
  • Time query: requires cloning all number combinations...
  • Wikipedia/browser query: requires real-time voice generation...
  • Improved animations / themes.

Any thoughts, issues or improvements, I'll be happy to read them via github or Twitter!

🐦 @RoamingWorkshop