Customizing the Maker Faire Tokyo 2015 Makey-kun with koshian

I'm genuinely unsure how many people will ever hit this exact problem, but I was mildly stuck so here's a note. I didn't make any of this myself.

At the Maker Faire Tokyo 2015 soldering experience corner, you could build a little creature called "Makey-kun". Attach the separately sold koshian module and you can control its LED eyes. That's what it says — but nowhere does it explain how to actually do that.

Update (August 4):
Macnica has added an official explanation page.
Good kids should check the official site.

The koshian manual tells you koshian's specs, but without knowing Makey-kun's specs you can't do much with that.

After digging around I finally figured it out, so I'm writing it down here.

What is koshian?

Check on Amazon
Honestly, I wasn't sure either. Apparently it's a Bluetooth module. Despite half-pitch spacing it can fit in a breadboard. Supports GPIO, UART, and similar interfaces. It's a Cortex-M3 SiP module that can be controlled via JavaScript and even have its firmware rewritten. …wait, what? That's pretty impressive.

There's also a related product called konashi — koshian with a battery holder and pin sockets attached.

Connecting koshian to Makey-kun

Left: koshian. Right: Makey-kun. Makey-kun's eyes are standard full-color LEDs. The koshian is terrifyingly small.


Plug it into the connector on the back of Makey-kun. Done.

Install the app on iPhone

To control koshian from an iPhone app, the app normally needs Apple MFi certification. However, there's an app called konashi.js that is MFi certified and lets you write your own JavaScript.
App Store — konashi.js

Controlling Makey-kun's LED

First, insert batteries into Makey-kun and enable Bluetooth on your iPhone. At this point Makey-kun's eyes may stop glowing — that's apparently fine.

Open konashi.js and search for "konashi". Searching for "koshian" won't find it. Why?!

From the search results, select "Makey Eyes' Color Picker". A color picker screen appears and prompts you to choose a Bluetooth device — pick "konashi2-hogehoge". If no device appears, tap the reload button at the bottom of the screen.

With the device selected, tap a color in the picker and the LED changes to that color. Pressing the × button to go back makes the LED cycle through the colors you tapped in sequence. After pressing × to go back, Makey-kun's LED changes color according to its own whims.

Here's what it looks like:


Step two:


End result:


Since konashi.js lets you view the JavaScript source code, you could use it as a reference to write your own code to control Makey-kun's LED however you like.

And that, I suspect, is exactly the point — get people hands-on with koshian through a fun, tangible demo. Well played, Macnica.