I also picked up a Logos Electromechanical Labs RGB LED Matrix Backpack<\/a> to fiddle with. I’ve been busy getting I2C devices working with my Rpi and thought this would be a fun addition! (I’ve previously fiddled with them on the Arduino, but the Wire library on Arduino leaves much to be desired in terms of correctness). UPDATE:<\/strong> the backpack works fine with the Pi – it was the nut behind the wheel that was the problem. More in an upcoming post. \ud83d\ude00<\/p>\n My most unique purchase was the HexBright FLEX 500 lumen Arduino-powered LED flashlight<\/a>! \ud83d\ude00 I was able to reprogram it pretty easily, though it doesn’t work with the Arduino IDE 1.5.x yet (also, when adding this target, merging their boards.txt to your boards.txt is the easy way to go… it didn’t work for me otherwise).<\/p>\n Note that I’m not thrilled with the charger that comes with the HexBright… I recently learned a LOT about off-brand USB chargers I was unaware of, particularly with regard to safety, from this EEVBlog post<\/a> among other places, and that makes me wary of chargers that look like knockoffs. While I’m happy to use cheaper parts when possible (I’m certainly not a hardware purist!), I expect the things I plug into my wall to have a a valid UL stamp on them at the very least. Bonus points if they spell the words right on it (“inter-mation equipment”? Looks like copy-pasta from a few other questionable chargers I’ve seen teardowns of – probably the same maker slaps whatever name you want on them). And no, that serial number is not “serial” at all on cheap chargers.<\/p>\nSadly, while it works with the Arduino, the backpack appears to hose to I2C bus on the Rpi (note that since this backpack is a 5V device I am using an appropriate level shifter<\/a> to interface it to the 3.3V Rpi). It seems that once it’s addressed (or even detected, e.g., via i2cdetect) it doesn’t correctly relinquish the bus until the\u00a0backpack is\u00a0disconnected and powered off. I’ve emailed them to see if they know why this is and how to fix it (I suspect it’s a firmware problem on the backpack, which is AVR-based… but I’m not sure how I’d update it yet).<\/del><\/em><\/p>\n
![\"20130519_181233\"](\"https:\/\/www.falatic.com\/wp-content\/uploads\/2013\/05\/20130519_181233-290x300.jpg\")
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