Month: October 2013

(Wow, just found out that this made Hack A Day, cool!)

I just finished the Nickelphone!  It’s a coin-based music keyboard. 15 nickels and 10 pennies act as touch sensors on a traditional 25-key piano-style layout. It can emit simple square wave tones through an onboard piezo buzzer, but its primary use is as a MIDI keyboard, so it can drive a full synthesizer (like FL Studio on PC). It’s based on an ATmega644 microcontroller, chosen because each key needs its own pin, and this chip has 32 data pins (8 of them analog inputs).  (Also, it happens to be the chip I got for free in when I placed my Atmel free sample order.)  It uses the “no extra parts” capacitive sensing method developed by Mario Becker and others.  For the MIDI output, I used the “last darned MIDI interface I’ll ever build” by Stephen Hobley (just the output part, which just uses one resistor).  The software is written in Arduino, with the “core” for the ATmega644 chip being adapted from the Sanguino project.  The Nickelphone was inspired by Linus Åkesson’s Chipophone and its follow-on, the bitbuf, both of which are totally awesome.

Read on for details…

Continue reading The Nickelphone→

Here’s an update to the Nickelphone (previous post here). It’s still made out of 15 nickels and 10 pennies acting as touch sensors on a traditional 25-key piano-style layout. It now has MIDI output and can detect any number of simultaneous key presses, so it works great with a full synthesizer (like FL Studio)!

I still need to do a full write up, and make it a little more well-built.

Here’s a work in progress video of my home-made musical instrument, the Nickelphone.

It’s a coin-based music keyboard.  15 nickels and 10 pennies act as touch sensors on a traditional 25-key piano-style layout.  It currently emits one tone at a time through a little piezo buzzer, but it will eventually emit MIDI signals so it can drive a full synthesizer (like FL Studio).  Based on an ATmega644 microcontroller and coded in Arduino with the CapacitiveSensor library for touch sensing.

I’ll do a full write-up here when it’s done.