Mar 292015
RasPiO Duino as a Lipo Monitor

I’ve been using lithium polymer (lipo) batteries since 2006, when I nervously shelled out £30 for a 3 cell 1600 mAh 10C HiModel lipo to power my EasyStar RC plane. I also spent about the same on a charger and balancer for it. Thankfully, all these things have come down a lot in price since then. I don’t think I’d expect to pay much more than £10 for an equivalent battery now. Typical lipo batteries for large devices have multiple cells. A lipo cell has a no-load resting voltage of 4.2 V when fully charged […more…]

Mar 092015
Pete Lomas Talks to Alex Eames at the Raspberry Pi Birthday Weekend

At the Raspberry Pi 3rd Birthday weekend, I met Pete Lomas for the first time. Pete is a Founding Trustee of the Raspberry Pi Foundation (in his spare time). For his day job, he’s Director of Engineering at Norcott Technologies. Pete has been involved in the Raspberry Pi story since very near the beginning. He designed the original model B & A production PCB. I had a chance to have a chat with him on day 2 of the Raspberry Pi birthday celebrations. If you’re a Pi geek or interested in how it all happened, […more…]

Feb 252015

Mainly video today. A little video showing a few simple examples of the sort of things you can do with the RasPiO Duino. Obviously you can do much more sophisticated things too. My next step will be to control the speed of the LEDs using the light sensor and the analog inputs. Endless fun, and useful too, when you think that an LED could represent any device you wanted to control… Don’t forget to check out the RasPiO Duino KickStarter, which finishes in a few days,

Jan 282015
Hacking HDMIPi Power Switch with Feedback

In a recent post, I showed you how to hack the HDMIPi power switch so that you can turn the screen on and off from the Pi. But no sooner had I done that than my friend Peter Onion, wondering if there was a way to detect if the LCD is on or off in case it gets “out of sync”, tweeted this… @RasPiTV Is there a switched 3v3 supply to the LCD pannel ? Wire that to a GPIO input pin ? Or can you test monitor "on" via hdmi ? — Peter Onion […more…]

Jan 142015
Hacking HDMIPi Power Switch

The HDMIPi driver board is a fairly complex design. I didn’t design it, although I did have some input into the feature list. I don’t fully understand how it works (something to do with the magic white smoke in the chips, I think), but I have messed around with it probably as much as anyone. Recently, several people have been asking if we can switch HDMIPi on and off programmatically from the Pi. Göran Roseen wants to be able to do it with this HDMIPi based clock… @Raspberry_Pi wall clock with go-to-school indicator that goes […more…]

Dec 082014
CamJam PiWars

On Saturday was the first PiWars competition at Cambridge Raspberry Jam (#CamJam). It was an excellent event. I was one of the judges, which proved to be quite difficult, but a lot of fun. The whole day went very well, there were several competition events… Sumo – Robots trying to push each other beyond the boundary Obstacle course – negotiate a range of different obstacles, some of which were positively evil Speed test (straight line) Line following – following a twisty, turny course Golf – try to direct the ball into the hole as efficiently […more…]

Dec 062014
CamJam Edukit 2 Launches at PiWars

Today the CamJam Edukit 2 is being launched at the first Cambridge Raspberry Jam PiWars event. I’ll be judging the smallest robot and the best non-competing robot categories at PiWars, but today’s blog is about the kit. This is the second kit in the series, which adds some sensors (temperature, light and PIR) into the bundle. The full kit contents is shown and described below. What’s in the Kit? A 400 point bread board including dual power rails Immersable DS18B20 temperature sensor Light Dependent Resistor (LDR) Passive InfraRed (PIR) sensor Piezo buzzer 4 male-male blue […more…]

Nov 262014
Gert VGA 666 review and video

Aaron Shaw from Pi-Supply sent me one of his early Gert VGA 666 adaptors for testing and comment, so I thought I’d share my findings. I followed the diagram in Gert’s manual. It’s a fairly simple build, just 20 resistors and two connectors. It took about 20 minutes, being careful to get all the resistors in the right places. The hardest part was the stacking header. The final product will ship with a slightly shorter stacking header. This should be a bit easier to solder. To get it working on the Pi, you need to […more…]

Nov 142014
The Raspberry Pi Family

Now we have the A+, I thought it’d be a good time to celebrate its ‘birth’ by having a rundown of the various mass-produced models of Raspberry Pi. I had a look through my collection and was somewhat surprised to see that I have 10 different variants of Raspberry Pi now. There is one I don’t have, but more about that later. Here’s the family photo. You can click it for a higher resolution version. Rev 1 Model B In row 1, column 1 we have the Rev 1 model B. Although I was up […more…]

Nov 122014
Raspberry Pi A+ How Much Power Does It Need?

Two Raspberry Pi A+ arrived from Farnell yesterday, so I spent the afternoon doing some power measurements. I also made a comparison video showing power measurements for an A+, a B+ and an old model A Pi. As before, when I did a similar thing for the B+, I used my trusty eMeter. But this time I used it inline with an ISO-TECH IPS 3303D bench power supply (at 5.2V) to corroborate the readings. Methodology I wanted to see how much current each Pi would consume under four circumstances…. Idling in command line – low […more…]