How to create a microbit piano

In this article we look at a Mini Piano Module that you can connect to your micro:bit.

The module uses a TTP229 which has 13 touch keys connected to it through an I2C interface, the board also has 4 WS2812B RGB LEDs fitted to it which can display 16777216 colors. There is also a buzzer fitted to the board which can play a note depending on whatever key you press.

In the following image you can see me using the module

Parts List

The piano module costs about $17, so you can get this and a micro:bit for under $40. Here are a couple of links to the products

Pinout

The module connects through an edge connector and uses the following pins

Code

The waveshare wiki has some code example and instructions on using the Block editor but here is a python example based on a user code example.

Copy this into the micro:bit python editor at https://python.microbit.org/v/1.1 , now click on download and drag the hex file to the drive that was created on your PC when your micro:bit was plugged in, the hex file will be programmed into your micro:bit and you should have a working mini piano

[codesyntax lang=”python”]

# Add your Python code here. E.g.
from microbit import *
import neopixel
import music
from random import randint

rgb = neopixel.NeoPixel(pin1, 4)

class PIANO():
    def __init__(self):
        #The piano key corresponds to the touch screen value.
        self.Zero = 0x0000
        self.C    = 0x0001
        self.bD   = 0x0002
        self.D    = 0x0004
        self.bE   = 0x0008
        self.E    = 0x0010
        self.F    = 0x0020
        self.bG   = 0x0040
        self.G    = 0x0080
        self.bA   = 0x0100
        self.A    = 0x0200
        self.bB   = 0x0400
        self.B    = 0x0800
        self.C1   = 0x1000
        self.play = self.Zero

    def TouchPress(self):
        try:
            arr = i2c.read(0x57, 2)
            val = arr[0] + arr[1] * 256
        except OSError:
            val = 0xffff
        return val

    def ShowRGB(self,RGB):
        for rgb_id in range(0, 4):
            rgb[rgb_id] = (RGB[rgb_id][0], RGB[rgb_id][1], RGB[rgb_id][2])
            rgb.show()

    def Color(self):
        red   = randint(0, 30)
        green = randint(0, 30)
        blue  = randint(0, 30)
        for rgb_id in range(0, 4):
            rgb[rgb_id] = (red, green, blue)
        return rgb
    
    def PlayPiano(self):
        TPval = self.TouchPress()
        if TPval & self.play != 0:
            TPval = TPval & self.play
        elif TPval == self.C:
            self.ShowRGB(self.Color())
            music.pitch(262, wait=False)
        elif TPval == self.bD:
            self.ShowRGB(self.Color())
            music.pitch(277, wait=False)
        elif TPval == self.D:
            self.ShowRGB(self.Color())
            music.pitch(294, wait=False)
        elif TPval == self.bE:
            self.ShowRGB(self.Color())
            music.pitch(311, wait=False)
        elif TPval == self.E:
            self.ShowRGB(self.Color())
            music.pitch(330, wait=False)
        elif TPval == self.F:
            self.ShowRGB(self.Color())
            music.pitch(349, wait=False)
        elif TPval == self.bG:
            self.ShowRGB(self.Color())
            music.pitch(370, wait=False)
        elif TPval == self.G:
            self.ShowRGB(self.Color())
            music.pitch(392, wait=False)
        elif TPval == self.bA:
            self.ShowRGB(self.Color())
            music.pitch(415, wait=False)
        elif TPval == self.A:
            self.ShowRGB(self.Color())
            music.pitch(440, wait=False)
        elif TPval == self.bB:
            self.ShowRGB(self.Color())
            music.pitch(466, wait=False)
        elif TPval == self.B:
            self.ShowRGB(self.Color())
            music.pitch(494, wait=False)
        elif TPval == self.C1:
            self.ShowRGB(self.Color())
            music.pitch(523, wait=False)
        elif TPval == self.Zero:
            rgb.clear()
            music.stop()
        if TPval != 0xffff:
            self.play = TPval

Piano = PIANO()
while True:
    Piano.PlayPiano()

[/codesyntax]

The code is also available from https://github.com/getelectronics/Microbitlearning

Video Usage

Here you can see me testing the piano module, this is using the code example above

Links

User manual – https://www.waveshare.com/w/upload/a/a4/Piano_for_microbit_User_Manual_EN.pdf