Back in November I made a Raspberry Pi controlled “light and fan relay switching” demo that you may have seen before on the Official Raspberry Pi blog. Before it appeared on the Raspberry Pi web site, I’d previously displayed it at Milton Keynes and Oxford Raspberry Jams and I’d also taken it along to let my year 5 ICT class have a go with it. Did they like it? You can see for yourselves in the video what the year 5s thought of it. I didn’t tell them what was going to happen, as I […more…]
Quick edit of Anthony Stirk’s stream from today’s Pi balloon launch. Unofficial RasPi.TV vid ;) Here a photo from a couple of hours into the flight
Mike Brojak from DesignSpark, whose voice you can hear in the video, asked me to put together a Wii controller flag-waving demo (plus other bits) on their new PiGo board. You may remember catching a glimpse of it in the flag waving video I produced a few weeks ago? This demo was destined for the Electronica exhibition in Shanghai, and I’ve just received a link to a little video the guys shot while they were there. (Thanks Yan :) ) Apparently it was well received, worked really well and only needed rebooting once in three […more…]
The Tandy Multiface is a brand new I/O interface board for the Raspberry Pi designed by Darren Grant from Tandy. The reason it came about is that, back in September 2012, Tandy was marketing a Gertboard kit, having bought a supply of official Gertboard PCBs from Farnell. This was a bit of a coup because Tandy beat Farnell to the punch with their own product. Farnell struggled to get their ducks in a row (I seem to remember comments about a shortage of one of the chips) and launched their kit about a month later. […more…]
Over the last couple of weeks the pace of development for Python programmers who like to dabble in GPIO has gone up a gear. Both main GPIO systems for Python on the Raspberry Pi have been getting some enhancements. RPi.GPIO, now at version 0.5.2a, has interrupts and threaded callback capability. You will probably have seen my three recent posts showing how to use those. WiringPi for Python version 2 is in Beta testing. I discovered two bugs while I was trying it out. Both of those have been squashed. One by Gordon “Drogon” Henderson in […more…]
Nicholas Luzzietti, who runs Bitcrafts, based in Dresden, sent me a review copy of one of his Bramble cases for the Raspberry Pi. It’s a laser cut, 3 layer birch ply finger-jointed box construction. Mine has a very nice Raspberry Pi logo lasered into the top, but other variants are available. All the holes are in the right places and are a good fit for all the ports. All the parts fit together very well – so well in fact that no glue is needed. I wonder if they will loosen with time? The case […more…]
The Guzunty Pi board is an open source Complex Programmable Logic Device (CPLD) add-on for the Raspberry Pi. Derek Campbell is behind this project, and has clearly spent a lot of time and effort putting it all together. He describes it… “a CPLD is like several large breadboards laid out on your desk, full of every combination of logic devices you are ever going to need. It is waiting to be told what to do. It doesn’t need a host of jumper wires like a breadboard would. It can be reprogrammed again and again (even […more…]
People seem very reticent about soldering headers to their Pis. Nobody else seems to be blogging or vlogging about it.* D’you know what? I think it was a really magnificent oversight that the original Raspberry Pis shipped with the 26 pin GPIO header on. In case you didn’t know, the original plan was to leave them off, but they didn’t get deleted from the design before the factory quoted for manufacturing – and they’ve stayed on ever since. Without that happy accident, I don’t think I would have ‘gotten’ so heavily into interfacing. You see, […more…]
Multiple threaded callback interrupts in Python We’ve been learning about interrupts this week because of the brand new interrupt capabilities of RPi.GPIO. We covered a simple “wait for” interrupt in part 1, threaded callback interrupt and button debouncing in part 2 and today we’re getting sophisticated with multiple threaded callbacks. “WoooooooooOOOOOOOOOOOOOOOooooooooooo”, I hear you say. ;) Well actually, we’re not doing much that’s very different from last time, except, now there’s more of it. We’ll add another button and another threaded callback function the same as the first one (but on a different GPIO port). […more…]
Interrupts are an efficient way for a program to be able to respond immediately to a specific event. In the previous article I explained the basics of using interrupts in RPi.GPIO and gave an example of a simple “wait for an event” interrupt program. In this second article I will introduce “threaded callback” which opens up a lot of new possibilities. Threaded callback – what the heck is that? I know it sounds complicated. And it probably is complicated in the C code it’s written in, but we’re Pythonites and we don’t have to go […more…]