Data Sheet

Board Layout:

:KLEF Piano for BBC micro:bit

www.kitronik.co.uk/5631

The :KLEF Piano is a musical instrument board, utilising the BBC micro:bit

(connected via a standard card slot connector) to process capacitive touch

sensor signals and output audio signals to an amplifier and speaker.

The Piano has 15 capacitive touch pads, with 13 arranged as a single octave on a

piano keyboard and 2 as up/down function buttons. The capacitive touch sensor

(AT42QT2160) registers changes in capacitance on the pads and sends a signal to

the BBC micro:bit via the I2C protocol to tell it which pad was touched. The

software on the BBC micro:bit can be configured to send specific audio signals to

be played through the speaker, depending on which key is pressed. It can also be

setup to provide a variety of other output options, including sending signals to

other BBC micro:bit boards; whether they are physically attached to the Link

header connector, or communicating over the radio.

Power is provided via a 5V micro USB connector, and the board then produces a

regulated 3.3V supply which is fed into the 3V and GND connections to power

the connected BBC micro:bit, removing the need to power the BBC micro:bit

separately. This also powers the capacitive touch sensor IC and audio amplifier.

Inserting a BBC micro:bit:

To use the Piano, the BBC micro:bit should be inserted firmly into the edge

connector, either way round. If the Link header is being used, the BBC micro:bit

LED display should be facing the Piano keys.

Examples: For some further ideas for what you could do with the piano, go to:

http://www.kitronik.co.uk/5631

micro:bit

Connector

Speaker

Micro USB

Connector

Amplifier IC

Link Header

Capacitive

Touch Sensor IC

Piano Keyboard Touch PadsUp/Down Function

Touch Pads

3.3mm

Mounting Holes

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:KLEF Piano for BBC micro:bit www.kitronik.co.uk/5631 The :KLEF Piano is a musical instrument board, utilising the BBC micro:bit (connected via a standard card slot connector) to process capacitive touch sensor signals and output audio signals to an amplifier and speaker. The Piano has 15 capacitive touch pads, with 13 arranged as a single octave on a piano keyboard and 2 as up/down function buttons.
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:KLEF Piano for BBC micro:bit www.kitronik.co.
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:KLEF Piano for BBC micro:bit www.kitronik.co.uk/5631 Electrical Information Operating Voltage (5V micro USB Supply) +5.0V Regulated Voltage +3.3V Max Supply Current (Piano key press + micro:bit LEDs + Speaker Output) 350mA External Connections (Link Header) All BBC micro:bit Pins (IO Pins 5mA max sink/source current) Power Supply via Link Header to External Devices 3.
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:KLEF Piano for BBC micro:bit www.kitronik.co.uk/5631 Microsoft MakeCode Blocks Editor Code The program shown to the left was created using the Microsoft MakeCode Blocks Editor for the BBC micro:bit. It enables the piano to play different notes through the on board speaker, depending on which keys are pressed.