Sep 222014
 
Programming a KickStarter Tracker in Python. Part 1.

Ever since the HDMIPi KickStarter I’ve been very interested in watching the progress of other campaigns. I’m following four or five Pi-based campaigns at the moment. Are they going to make it? Are they not? It’s nice to keep an eye on things. But monitoring more than one or two wastes a lot of time. Wouldn’t it be nice if I could have a little computer and screen set up so that it checked these campaigns, say, once a minute, and reported on how they’re doing? I know there’s a decent Python library called urllib2. [...more...]

Sep 152014
 
Raspberry Pi SmartWatch Joke

A Raspberry Pi SmartWatch? You’re kidding me right? Errrm. Yes. I mean… Well… This has a lot of the functionality of a smartwatch, but it wasn’t built for that purpose. It’s a little big, for starters. Let me back up and explain. Last week, Apple released photos of their new smartwatch. Twitter, Google+ and every social network was awash with photos, comparison photos, criticism, analysis and good old-fashioned Apple-hating. By Thursday I was rather bored of it all, so I decided to make a joke tweet. I had this rather large Vacuum Fluorescent Display (VFD) [...more...]

Sep 012014
 
RPi.GPIO - port function checker

A few weeks ago I blogged about RPi.GPIO updates for the model B and updated my RPi.GPIO documentation and quick reference sheets. But there was one feature I held back on because I needed a bit more time to mess about with it. (And then got busy with other things.) So What Was It? gpio_function() Another RPi.GPIO feature that sneaked in while I wasn’t looking is gpio_function() This is a feature that’s been inserted in RPi.GPIO to enable you to query the setup status of a port to see how it’s configured. import RPi.GPIO as [...more...]

Aug 222014
 
New Raspberry Pi Speaker from ThePiHut

I got a new speaker in the post yesterday morning. It’s been redesigned specifically for the Raspberry Pi by ThePiHut. I charged it for a few hours (it has an internal lipo battery, which powers it for 7 hours of use) and then plugged it into the 3.5mm stereo outlet of an HDMIPi screen. This takes the sound from the HDMI output of the Pi (so it’s digital and high quality, much better than the Pi’s analog output). I tested it with Bug Buck Bunny, which has superb graphics and sound. It also makes an [...more...]

Aug 182014
 
PiHut WiFi dongle vs Edimax - Power Usage

At the May CamJam, Jamie from The Pi Hut handed me a couple of his Raspberry Pi Wifi dongles for testing. I did some measurements a week or two later on a Raspberry Pi model B and sent them to Jamie. But I thought it would be fun to repeat this now with the new B+ and show all the results together. I’m doing a comparison test against the Edimax EW-7811Un which is my current ‘Go To wifi dongle’. Differences & Similarities? The Edimax is very slightly smaller. Both have blue LED activity indicators. The [...more...]

Aug 132014
 
New Port ID Board for the Raspberry Pi B+ - RasPiO Portsplus 2

Today I’m launching the RasPiO Portsplus 2. It’s a simple port ID board for the Raspberry Pi model B+. It’s available over at http://rasp.io/portsplus2 but full information below… RasPiO® Portsplus 2 The RasPiO® Portsplus 2 board is designed for the new Raspberry Pi B+. It labels the ports clearly for you so that you don’t need to count pins. This will help you avoid wiring errors and damage… You can slip it over the B+ GPIO header if you want, or hold it next to the header (many people tell me they do this – and this [...more...]

Jul 262014
 
RPi.GPIO Quick Reference updated for Raspberry Pi B+

Having brought my RPi.GPIO documentation (almost) up-to-date with the previous blog post, I realised it was time to update my RPi.GPIO Quick Reference ‘cheat sheet’ as well. It’s quite a useful reference. Page 1 gives you the basic RPi.GPIO commands and usage. I like to take one of these the Jams in case someone needs help and I can’t remember the necessary commands. Page 2 has a Raspberry Pi GPIO pinout diagram for all versions (except compute module). This part has been updated to add the pinouts for the B+. Page 3 gives a list [...more...]

Jul 252014
 
RPi.GPIO update and detecting BOTH rising and falling edges

A few days ago, Ben Croston updated the RPi.GPIO Python library so that the ‘board’ pin numbering system would work with all of the pins on the B+. It doesn’t really affect the way I work, as I always use BCM port numbers. They already worked on the B+ and the compute module. While he was at it, he made a couple of bug-fix tweaks. Looking at what was tweaked, I realised there are a couple of features of RPi.GPIO that I hadn’t yet documented. In this blog post I hope to update my RPi.GPIO [...more...]

Jul 182014
 
Raspberry Pi B+ testing all the GPIO ports

I wanted to check out the GPIO ports on the Raspberry Pi B+. The new B+ has 26 ports available for GPIO work. The previous model B had 17 on the main (P1) header and four more on the now deleted P5 header. The top 26 pins are all the same, but the 14 new pins contain 9 GPIO ports. There’s a full explanation of the ports in the diagram here… How to Test All 26 ports? Why with LEDs of course. You can do it by connecting an LED and resistor (~330 Ohms is [...more...]

Jul 162014
 
How Much Less Power does the Raspberry Pi B+ use than the old model B?

The power circuit on the new Raspberry Pi B+ has been completely redesigned. It now has an efficient switching regulator. So I decided to take my trusty emeter, a tool I spent far too much money on a few years ago whilst in the grip of the aero-modelling ‘bug’, and make some measurements. I measured the current and voltage going into the Raspberry Pi. The emeter has a calibrated shunt (small blue rectange in the photo with ‘battery’ and ‘load’ at each end) that’s good for up to 20 Amps. This is a way of [...more...]