hacking

DFRobot FIT0441 pinout

I ordered two FIT0441 brushless motors for use in v2 of my balancing robot. The DFRobot wiki page on the motor is incorrect so I thought I’d blog about it so someone else can find it 🙂

Maker Faire Bodensee

We went to Maker Faire Bodensee on the weekend. The kids spent so much time with Paula Pongratz’s Post-apocalyptic jewlery that they missed most of the rest (heh). Other standouts were the breadboard / pus pin based electronic organ from [

Sending music over light

Someone recently mentioned that you can ‘hear’ a TV remote control by hooking a solar panel to a speaker and pointing the remote at it. It was a rainy weekend this weekend, so my son and I gave it a go:

Web connected NeoPixel ring

It’s taken a while (as you can tell from the date on the box), but here’s my web connected NeoPixel ring: https://juju.net.nz/michaelh/blog/wp-content/uploads/2016/02/Vid-20160207-165253-1.m4v Chroma trail: a comet with a trail that cycles through the colours of the rainbow.

Fading text on an OLED screen

Here’s my hack of the moment: text fading in on a OLIMEX 128×64 OLED display. The interesting bit is that this is a TTF font which is rendered by SDL2 into a buffer, dithered into black and white using Floyd-Steinberg error diffusion, and then written out using the Intel IoT upm display driver.

Adding buttons on the Linkit Smart

Here’s what I found out while trying to add buttons to the OpenWrt based Linkit Smart. The flow is: Keys are defined in target/linux/ramips/dts/LINKIT7688.dts gpio-button-hotplug emulates gpio-keys-polled and generates uevents. The uevent is received onver netlink by procd in plug/hotplug.

Hack of the day: scrolling text

I did a quick hack today and wrote a scrolling text app for an Adafruit 8×8 LED display I had lying about: https://juju.net.nz/michaelh/blog/wp-content/uploads/2016/01/udisplay-with-scrolling-text.mp4 The app is written in C++ using the Intel mraa I/O library (which looks pretty good) and running on a WRTNODE MIPS dev board with OpenWrt.

The Boost libraries

I’ve been hacking on a personal project to make it easier to expose HTTP based devices that are behind a restrictive NAT or firewall. The code needs to run on a OpenWrt based MIPS board 1 which limits my language choice – Python3 is out as it’s too big, and Go on MIPS32 via gccgo on OpenWrt is… tricky 2.