I’ve released a toy compiler for the PL/0 educational language at https://juju.net.nz/src/cgit.cgi/pl0.git/ or https://github.com/nzmichaelh/pl0. I did this as, despite working with compilers for a fair part of my life, I’d never written one from scratch.
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 [
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:
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.
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.
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.
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.
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.
I’m hacking on a project to hook a NeoPixel ring up to the internet. I don’t have a good reason why, but it’s a good excuse to work with OpenWrt, TURN servers, and some blinking lights.
Hobbyking had a free shipping promotion recently, so I picked up a Wing Wing Z-84 flying wing like all the cool kids have. It’s quite fun if a bit noisy. The 1500 mAh 2S batter lasts 15 minutes, which is crazy long, and it’s quite interesting how a pusher propeller changes climbs and loops – you need momentum as there’s no propeller to caster under.