4×4 matrix piano (simple demo)

This week, we were tasked to do something with analog input, and a tone-based interface. 🎡

I worked on something which I felt was technically challenging from an Arduino software stance.Β  (I would have liked to make a container for it, if only I had the time. The interface itself is more bare bones!)

I was inspired by the form factor of Launchpad-type interfaces. You can see Shawn Wasabi using one here:

On my last trip to Tinkersphere, I found one of these 4×4 button matrixes. It’s like the cave-man version of Shawn Wasabi’s instrument.

img_20171002_184746-e1507085933849.jpg

There are 8 pins total. 4 pins correspond to columns, 4 pins correspond to rows.

I wanted to build something where each button would correspond to a note, so you could play different songs. Like a puny, gridded piano!

****
I relied on several websites for instructions and debugging help. I’ve linked to most of them at the bottom of this post.

In order to set up the matrix grid, I used code which looked like this…

The mapping wasn’t intuitive for me; I used the Serial Monitor and old-fashioned pencil-paper to keep track of which values corresponded with which keys.

img_20171002_184832.jpg

img_20171002_185150.jpg

Early on, I was able to use “case… break… case… break…” formatting to conditionally turn on and off an LED.

4x4_led.gif

After importing the tone library, I struggled with debugging my Piezo and code for a couple of hours. Incorrect wiring, messy functions, variable salad!

screen-shot-2017-10-03-at-10-54-28-pm.png

My final working code plays a frequency based on what key was pressed. It also has a “toneOffset” which can controlled by a potentiometer to change the pitch of all keys.

****
Here are some the resources I referenced when building this:

4×4 Keypad

Piezo + Tone Control

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s