Welcome to this tutorial on creating a mechanical macro keyboard PCB using EasyEDA and Raspberry Pi Pico with Circuit Python.

Macro keyboards are an excellent way to streamline your workflow and increase productivity. With a macro keyboard, you can automate repetitive tasks, execute complex commands with a single key press, and customize your keyboard layout to your needs.

Supplies

Here is the breakdown of components needed for the Macro Keyboard (assuming you have basic tools):

Custom PCB 1

Raspberry Pi Pico 1

Mechanical Switches 11

1.3 OLED I2C 1

Rotary encoder 2

Resistors - 10k 6

2.54 20 pin Header 2

2.54 4 pin Header 1

WS2810B LED strip 18

Miscellaneous Depending on Design

Step 1: Schematic Diagram

The schematic diagram is available to view here. The design is straightforward as each button was connected to a GPIO pin to the Raspberry Pi Pico. The reason for not using a matrix is due to limited space on a 10 x 10 cm board size, which meant individual GPIO pins could be used. This also means that diodes are not needed to prevent ghosting effect when pressing the keys. The board is kept this dimension to minimize the total cost of the board. The screen can be removed if more buttons are needed, but will require a new PCB design and updated code.

Step 2: PCB Design

The PCB design is simple which allows you to mount the PCB easily into different enclosures with the 4 mounting holes in the corners. The placement of the Pico was placed on the bottom layer which will be connected through header pins. If anyone in the community have suggestions on how to improve the layout or want to contribute reach out as I would like to see how this project can be taken further.

Step 3: Order PCB (JLCPCB)

The PCB was ordered through JLCPCB. They offer great PCBs at a low cost and have promotions and coupons available throughout the year. You can sign up using here, or using the following link:

https://jlcpcb.com/?from=Nerd that will support me as a creator to keep making content that is accessible and open source at no charge to you.

Ordering the PCB is very simple:

Click on Add Gerber file , leave all the settings as default given. You might want change the PCB color. hen after a few days depending on your location you will receive your great quality PCB.

Step 4: Circuit Python

CircuitPython is a variant of the Python programming language designed for microcontrollers, specifically those based on the ARM Cortex-M family of processors. It allows developers to write Python code that can interact with hardware components and sensors, making it a popular choice for DIY electronics projects.

One advantage of using CircuitPython for building a macro keyboard is that it includes the HID (Human Interface Device) library, which allows microcontrollers to act as USB input devices such as keyboards, mice, and gamepads. This means that with CircuitPython, you can program your microcontroller to act like a keyboard and send keystrokes to your computer when a button is pressed on your macro keyboard.

Another advantage of CircuitPython is its ease of use and rapid prototyping capabilities. Since CircuitPython is an interpreted language, developers can write and test code on their computer before uploading it to the microcontroller. Additionally, CircuitPython comes with a large number of built-in libraries and modules that simplify programming for common hardware components, such as OLED displays, sensors, and LED strips. This can save a lot of time and effort compared to writing low-level code in C or assembly language

Step 5: HID Library

In order to get the Raspberry Pi Pico to work as an macro keyboard we need to install a Human Interface Device Library from Adafruit Circuit Python library.

You need to create a folder on your Raspberry Pi Pico named “adafruit_hid” and upload the following files in the folder. You can download the files on my GitHub repository. It is also available on Circuit Python website but in order to keep version control for this specific tutorial along with the video I recommend you download it from my GitHub repository.

Step 6: Code

To follow along with this tutorial make sure you flash the Pico with CircuitPython 7.2.3 which you can download here:

CircuitPython - https://github.com/Guitarman9119/Raspberry-Pi-Pico-/raw/main/Pico%20MacroKeyboard%20V2/Code.rar

All the code can be downloaded here:

Link - https://github.com/Guitarman9119/Raspberry-Pi-Pico-/raw/main/Pico%20MacroKeyboard%20V2/Code.rar

Upload the above code to your Raspberry Pi Pico which will show as a storage device in your computer.

Step 7: Creating the Custom Mode File

To begin, we’ll create a new Python file for our custom mode. Let’s name it my_custom_mode.py. Inside this file, we’ll define a function called handle_keypress to handle the keypresses and execute macros specific to our custom mode. Here’s an example of how my_custom_mode.py might look:

import time
import board, busio, displayio, os, terminalio
import digitalio
import time
from adafruit_hid.keycode import Keycode
from adafruit_hid.consumer_control_code import ConsumerControlCode
from adafruit_display_text import label
import adafruit_displayio_ssd1306

def update_screen(splash, macro_name, display):
    # Update the macro label
    center_x = (118 - len(macro_name) * 6) // 2 + 5
    macro_label = label.Label(terminalio.FONT, text=macro_name, color=0xFFFF00, x=center_x, y=50)
    splash.append(macro_label)
    display.refresh()
    # Wait for 1 seconds
    time.sleep(1)
    # Remove the macro label after 1 seconds
    splash.remove(macro_label)
    display.refresh()

def handle_keypress(key, cc, write_text, keyboard, SW1, SW2, rotary_changed_left, rotary_changed_right, splash, display ):

    # Macro names or actions
    # Change the macro names * 
    macro_names = {
        0: "*",
        1: "*",
        2: "*",
        3: "*",
        4: "*",
        5: "*",
        6: "*",
        7: "*",
        8: "*",
        9: "*",
        10: "*",
        11: "*",
        # Add more macro names and their corresponding keys as needed
    }

    #Repkace keyboard.send(Keycode.G) with your macro code

    if key[0].value:
        keyboard.send(Keycode.G)
        time.sleep(0.2)
        update_screen(splash, macro_names[0], display)

    if key[1].value:
        keyboard.send(Keycode.G)
        time.sleep(0.2)
        update_screen(splash, macro_names[1], display)

    if key[2].value:
        keyboard.send(Keycode.G)
        time.sleep(0.2)
        update_screen(splash, macro_names[2], display)

    if key[3].value:
        cc.send(ConsumerControlCode.VOLUME_INCREMENT)
        time.sleep(0.2)
        update_screen(splash, macro_names[3], display)

    if key[4].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[4], display)

    if key[5].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[5], display)

    if key[6].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[6], display)

    if key[7].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[7], display)

    if key[8].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[8], display)


    if key[9].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[9], display)

    if key[10].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[10], display)

    if key[11].value:
        keyboard.send(Keycode.G)
        time.sleep(0.3)
        update_screen(splash, macro_names[10], display)

    #Rotary encoder 1 turned clockwise     
    if rotary_changed_left() == True:
        cc.send(ConsumerControlCode.VOLUME_INCREMENT)
        time.sleep(0.01)

    elif rotary_changed_left() == False:
        cc.send(ConsumerControlCode.VOLUME_DECREMENT)
        time.sleep(0.01)


    #Rotary encoder 2 turned clockwise
    if rotary_changed_right() == True:
        cc.send(ConsumerControlCode.VOLUME_INCREMENT)
        time.sleep(0.01)

    elif rotary_changed_right() == False:
        cc.send(ConsumerControlCode.VOLUME_DECREMENT)
        time.sleep(0.01)

    if not SW1.value:
        keyboard.send(Keycode.G)
        time.sleep(0.2)

    if not SW2.value:
        keyboard.send(Keycode.G)
        time.sleep(0.2)

    time.sleep(0.0001)

Now that we have our custom mode defined in my_custom_mode.py, let’s import it into the code.py script to make it an integral part of our macro keyboard. Here’s how you can import the custom mode:

# code.py

# Import the custom mode
from my_custom_mode import handle_keypress as my_custom_mode_handle_keypress

Adding the Custom Mode to mode_names Dictionary For better user experience, we should add our custom mode name to the mode_names dictionary so that it appears on the OLED display. Let’s update the dictionary in the code.py script:

# code.py

# List of predefined modes and their associated functions
mode_names = {1: 'Blender', 2: 'Windows', 3: 'Premier Pro', 4: "After Effects", 5: "Fusion360", 6: "My Custom Mode"}

Congratulations! You’ve successfully added a custom mode to your Raspberry Pi Pico Macro Keyboard. With this new mode, you can now unleash a whole new world of possibilities and personalize your macro keyboard to suit your unique needs.

Feel free to experiment and create custom macros that cater to your workflow and preferences. Whether it’s for productivity, entertainment, or anything in between, your custom mode will make your macro keyboard truly one-of-a-kind.