Students at the Canberra Institute of Technology have taken a bunch of old DVI monitors and, together with a Pi for each monitor, have created a video wall. This is a great way of recycling old monitors! It doesn’t look like they’ve shared their code, which is a shame, but you can read more about their efforts here.
Hopefully the headline alone should have got you intrigued.
Daniel Fett from Germany has developed a digital dartboard (PiDart) where the dart hits are registered by an Arduino Mega and then sent to the Pi which records the hits and displays the scores on an HDMI screen.
Here’s a video of it in action:
Matthew Timmons-Brown, aka The Raspberry Pi Guy, has done another tutorial video. This time he tackles the complexities (or simplicities) of getting a Wiimote running in conjunction with your Pi. It’s very simple and he’s done some example code so that you can hack away without going back to first principles.
You need to have “git” installed for the tutorial. If you don’t, first run the following commands:
apt-get update
apt-get install git
Here’s the video:
Andrew Mulholland has developed a series of scripts called RaspberryPi-LTSP that allow you to boot the Raspberry Pi over a network. You start off by installing a minimal distro on the Pi’s SD card and then it goes and ‘gets’ the full operating system from a central network server. This means that the Pi is running as a ‘fat client’ – all the processing is done on the Pi but things like installed apps and the work you do on the Pi is held on the server. This is ideal for classrooms as it means that if you have a Pi SD card failure then you haven’t lost all the work that the Pi user had done. Here’s what he had to say about it at the Raspberry Jamboree in Manchester:
For more details, visit the GitHub project page here. You can talk to Andrew about it on Twitter: @gbaman1.
I was contacted by Shawn from UUGear, based in the Czech Republic, about their new 7-port hub and agreed to review it. So, here goes!
The UUGear Hub features 7 ports on a circuit board that is the same size as the Raspberry Pi itself. You can mount it (using the included metal spacers) above or below the Pi.
Here are the specs:
Here’s a video from Alex Eames over at RasPi.TV – it’s a quick walk-round and explanation of the features:
You’ve got three options to power the Pi from the hub. First, there are two header pins on the board which you can connect via female-to-female wire directly to the 5V and GND GPIO pins. Secondly, you can power the Pi over the USB bus (which you shouldn’t do, but you can switch the jumper to prevent this… but it works, so hey ho!) and thirdly you can plug the Pi into one of the board’s 7 USB ports. Below you can see a photo of the hub powering the Pi via the GPIO pins:
Now, obviously the amount of devices you’ll be able to successfully use will depend very much on your mini USB power supply. When I used it, I used a 2.1A supply that I happened to have (thank you very much Cyntech) so I could connect a lot of things to it. Here it is in action with 3 webcams, a keyboard, a mouse and a serial-to-USB cable connected to my old Windows CE HP Jornada.
I actually ran out of devices to connect up at that point! By using lsusb, I confirmed that all the devices were detected, although I didn’t actually use them at all, I just got the list up.
According to Shawn, he has successfully powered three Pis from it! Again, very much depends on your power supply. My attempt at doing this failed due to a dodgy cable, which was a shame (or it could’ve been because I was trying to power three model Bs and he used a model A as one of his). But here’s a photograph of Shawn’s successful experiment (all the Pis have wifi dongles too!):
Overall, this is a great hub. At the moment, you can only get it direct from UUGear but I would expect them to secure a UK distributor soon. It costs $29.50 from their store. This seems about right considering the manufacturing quality and the small size.
In conclusion, if you’re looking for a compact, quality hub with a lot of flexibility to power the Pi, or if you want one that can be mounted to the Pi, and which has an awful lot of ports, I highly recommend picking one up.
For the next few days (until Saturday 29th), there is a 10% off discount code – uugear-launch-2014 – that brings the cost of the hub down to about £16.
Read more on UUGear and decide if you want one. You can buy it from their store here.
Last week I described how in June 2012 pupils had modified some Python Software on the Raspberry Pi to make the attached Seven Segment Display count to …
…and I realised I had something which answered the pupil’s question…
“Yes! …but what does it do!?”
…something I could use for Raspberry Pi Workshops in schools!
I still only had one Raspberry Pi, but I had plans to buy at least 2 more. With 3 Raspberry Pi’s I could probably run Workshops with up to 9 pupils. But whilst I could buy 3 Raspberry Pi’s, I didn’t have 3 Keyboards, Mice and Monitors.
Keyboards and Mice were easy. Most schools had plenty of USB Keyboards and Mice for me to borrow, but as soon as the teachers realised the only usable video output connector on the Raspberry Pi was HDMI…
…I got the immediate response…
”Yes! …but all our monitors are VGA!”
…and there was no way schools were going to buy loads of HDMI TV’s just to run a few Raspberry Pi Workshops!
This seemed to be a bit of a road-block! I might be able to borrow 2 or 3 HDMI TV’s to run some workshops but it looked like a big barrier to the general acceptance of Raspberry Pi’s in schools!
A little bit of research was required! I had never taken much notice of how my PC attached to its monitor. I was familiar with the VGA input, but I found my PC’s monitor also had a DVI input…
…and that HDMI and DVI signals were compatible. So I attached my Raspberry Pi to the DVI input on my Monitor with a simple HDMI-to-DVI Cable…
…and it worked!
I went back into schools to see if they too had DVI as well as VGA inputs on their monitors. Unfortunately most did not! “When we bought our PC’s, we had to buy the lowest cost monitors, and they were the VGA-only ones!” was the usual answer.
At one school however the teacher said “I’ve got an HDMI-to-VGA Adapter box in the car” It was worth a go. It was a bit cumbersome since it had to be mains powered, but it prompted me to search for other HDMI-to-VGA Adapters.
Searching on Amazon I found this self-powered adapter made in the far-east by “Neewer”**…
…with a user comment saying they had successfully made it work with their Raspberry Pi by modifying the Raspberry Pi’s “config.txt” file. It was only £12.99 so I ordered one.
It worked! I now knew I could run Raspberry Pi Workshops in schools. But what is more, I could tell schools…
“You don’t need HDMI Monitors to use Raspberry Pi’s in schools!”
**The use of the original “Neewer” Adapters was not entirely trouble free as I will describe in a later blog entitled “Doh! There’s no sound!” but their current version may be OK. I have also tested 3 other HDMI-to-VGA Adapters and all three have aspects I think could be better so I have asked for clarification from the manufacturers. Hopefully by the end of this series of Blogs I can recommend at least one HDMI-to-VGA Adapter!
Next week I will look at how I developed a more comprehensive set of Software Challenges (and ordered a couple more Raspberry Pi’s) so I could run Raspberry Pi Workshops in Schools in a Blog entitled…
”What can you do with just Seven Segments?”
If you are interested in learning more about the Seven Segments of Pi visit my Web Site www.SevenSegmentsOfPi.com or watch the “Seven Segments of Pi” YouTube Video. You can also watch Carrie Anne Philbin playing “Figure Eight My Pi” at the CamJam, courtesy of Alex at RasPi TV.
Nevil Hunt
