Logitech Performance MX Middle switch

Just a heads up in case anyone else’s Logitech Performance MX starts acting up on the middle mouse button: The switch used is an E-Switch TL3315NF160Q.

Apparently sometimes a drop of hot-glue is enough, but in my case the switch itself was broken. The linked tutorial does give clear instructions on how to reach it though. If you’re handy with a hot-air gun, it’s easily replaced 🙂

96×48 full-color LED Matrix

LED Panels

A few years ago I built a red-only 32 pixels high, 96 pixels wide LED Matrix, and due to all the positive responses I sought out to do it again the year after with a bigger better matrix. I did some research into affordable solutions, and as usual ended up with Chinese vendors. I got my hands on about 10 32×16 RGB LED panels with a 1cm pixel pitch, and a HUB75 connection, quite similar to the ADAFruit 32×16 matrix. ADAFruit had a bunch of information on them, and there are several other places where they’re being used, so I figured I’d give it a shot. I even bought a Digilent Basys 2 FPGA development board, as these boards are apparently best driven by an FPGA, and I was willing to pick that up.

However, when I started working on it initially, I found out that the Basys 2 did not even have enough memory for 24-bit color, and with my microcontroller of choice at that moment (TI Stellaris) I did not get more than 16-bit color without flickering. While the panels looked fun, with 16-bit color everything still looked very basic, and very limited. Definitely not the neat full-color panels I had in mind. I figured I’d either have to shell out for a much more expensive FPGA, or buy one of the purpose-built LED drivers from china, both of which were out of my budget for this project. The panels disappeared in a box somewhere, only to be stumbled upon at least 2 year later.
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Flashing the ODROID-U2’s eMMC card without a reader

Why?

In the quest for the ideal XBMC set-top box, I’ve bought an ODROID-U2. It’s a small devboard with an Exynos 4412 quad-core Cortex-A9 processor. Pretty much the same chipset as the Samsung Galaxy S3 or the Note 2, which should be more than enough to power XBMC I figured. (Note: At this point it doesn’t run XBMC flawless yet, the menus work great and much faster than on the RPi or the Pivos XIOS DS, 720p content seems to work fine, but 1080 still stutters a bit. However, that’ll supposedly get fixed once XBMC upgrades to multi-core ffmpeg or the video decoder will be implemented)

While the ODROID will boot from MicroSD perfectly, there’s another option called eMMC that is supposedly much faster. If you buy it from them, it’ll include a small converter to microSD so you can flash it with a computer. However, as it turns out this converter is absolute garbage. it’s too big to fit into a regular uSD-SD converter, and even after I filed it down to the appropriate size, it still didn’t work.

So I had this nice box, with Android 4.0 pre-installed, but the one method to upgrade was broken.

Luckily, there’s another way to upgrade by booting to Ubuntu from a microSD card, and access the eMMC module on-board from there. I’ll detail how I did it here.

Continue reading Flashing the ODROID-U2’s eMMC card without a reader

OpenELEC on the Asus AT5IONT-I with sound over HDMI

For the past couple of months I’ve been running XBMC on a Windows 7 installation. Worked pretty much instantly after installing, but the boot times were horrible, and every now and then windows updates would nag. When I bought the box I briefly tried XBMCBuntu, but concluded that it was too much tinkering to get it working and gave up.

However, today I set out to give OpenELEC a try. Almost everything worked out of the box, except for audio over HDMI. I’ve tried most of the things on the wiki, but couldn’t get it to work in both the video as well as the XBMC menu. Most people seem to be satisfied with just the video, often calling the XBMC menu sounds “obnoxious”, but I’m rather fond of those, so I set out to fix it.

Here’s a quick guide on what I did.

Continue reading OpenELEC on the Asus AT5IONT-I with sound over HDMI

Dx.com’s Multi-Function 4WD Arduino Robot Car Kit

While browsing through DX.com’s new arrivals section, I stumbled upon this package:

Multi-Function 4WD Arduino Robot Car Kits

Seeing as I still had a bet with a friend to, at some point in our lives, do a real-life Robot Wars, I figured I’d give it a shot. It just got in a few days ago, so I figured I’d write a quick review. Continue reading Dx.com’s Multi-Function 4WD Arduino Robot Car Kit

Digital Addressable LED-strips

About a year ago, I ordered a few WS2801-type addressable RGB LED strips, and have been very happy with them since. Today I was curious how much they cost nowadays, and if anything new was out in China. It appears that a lot has changed since the last time I looked. Back then there were a few different chips, but the WS2801 was the only one doing 8-bit PWM, now there’s even a chip doing 12-bit PWM! However, it also appears that the protocol that was used back then (basic two-wire SPI) has been replaced by single-wire protocols requiring precise timing.

Seeing as there’s just too much choice and the information is scattered all over the place, I figured I’d do a summary of all I could find. Unfortunately I haven’t been able to actually get engineering samples of any of these strips, but I’m hoping that I can still compile a summary using only the datasheets. So here goes in alphabetical order! Continue reading Digital Addressable LED-strips