Pi Powered

Raspberry Pi Powered from BT Home Hub The Christmas break has given me an opportunity to get leave aside the pie and get out the Pi. In doing so I have discovered a really neat way of being able to keep the device permanently powered and connected.

Our broadband is provided by BT and as part of the package you are supplied with a router called a “BT Home Hub”. I have always known that there was a USB port on the back of the hub but until yesterday it hadn’t occurred to me to plug in the Pi. Lo and behold it provides enough power to drive the Pi. As an added bonus the Pi is now close enough to the router to be directly wired using the ethernet connection.

Of course this setup doesn’t allow for a monitor and so I am using the Pi “headless” i.e. connecting to it over SSH, which works really well.

Speaking of monitors it is occasionally useful to be able to connect the Pi to a screen. Eben and the team conceived the Pi as a modern day replacement for the BBC micro and the Sinclair Spectrum which were plugged into a household TV. I have never really bought this argument. While it is a great idea in practice it is not very practical as most modern TVs are huge in comparison to TVs when the likes of the BBC Micro was released. A Pi on a 40″ flat screen really doesn’t work very well as you need to be close to it to work and then you can’t see anything.

The solution is to use an existing VGA monitor with an HDMI to VGA convertor for the Pi. I bought this one from Amazon for just under £9. When I arrived I was disappointed to find that while the monitor detected a signal the screen remained resolutely blank. A quick look in the Raspberry Pi User Guide showed the issue.

There is a file that is read on boot called config.txt (bootconfig.txt) that provides settings for various things including the HDMI output. By uncommenting the first line to read as following and rebooting the monitor burst into life.:

hdmi_safe=1

The file is in boot and you just need to open it with a simple text editor, such as nano. If you are not comfortable with doing that – what on earth are you doing with a Raspberry Pi!

You can see some pictures of the setup below and the output on the Monitor. You can also click through to buy the excellent book from Amazon too.

Raspberry Pi with HDMI to VGA Output IMG_5956