Portable Raspberry Pi


Taking your Raspberry Pi on the road can be quite involved.

Normally we need a keyboard, mouse, power and a screen. Some of these components can be easily packed ready for hacking on the move. But some, namely the power and screen, require us to compromise in some way. But can we create a truly portable Raspberry Pi kit?

Kev and Rachel do a lot of travelling and they needed a portable kit that could be taken into meetings and used to demonstrate the power of the Raspberry Pi.

So my brief was simple

“Create a portable Raspberry Pi kit.”

 

Based on this brief I created my own requirements, having used the Pi “in the field” and understanding their needs.

The kit should be

  • Based on the latest Raspberry Pi
  • Be sturdy for transport
  • Use a common power source (micro USB)
  • Have access to the GPIO for add on boards

So what did I use?

We started by building the HDMIPi screen kit. This is a really robust and well thought out kit that provides an excellent 1280 x 800 pixel display inside a series of LASER cut acrylic layers.

The use of the acrylic layers enables the screen to be sandwiched between the layers, providing a tough shield for the delicate screen.

HDMIPi also comes with its own controller board that is used to route the HDMI output from our Raspberry Pi to the screen, but this board also provides a single point of input for a power supply, in this case the Tecknet IEP1500 power bank. The power bank provides 15000mAh of power and in our tests we saw approximately 5 hours of use from it.

We used a Raspberry Pi 3 in our build, ensuring that we have the latest version of this popular single board computer which is now powered by a quad code processor running at 1.2GHz! The Raspberry Pi 3 also comes with built in WIFI and Bluetooth, enabling our dynamic duo to have Internet access, but without taking up a USB port on the Pi.

The Raspberry Pi 3 is also cleverly hidden inside of the HDMIPi case, protecting it during long journeys, but with one slight problem, namely the GPIO pins are now behind the screen and not really within easy reach.

But we needn’t have worried as the Pirates of Sheffield, aka Pimoroni have created their own expansion board called the Black HAT Hacker. This board breaks out the GPIO pins to a PCB plate that connects to the GPIO via a ribbon cable. The Black HAT Hacker enables easy access to all of the GPIO pins and it can be used with other add on boards, such as the Astro Pi project’s Sense HAT. This will give the dynamic duo all of the flexibility that they need to “hack on the go!”

With the kit assembled our next goal is to create a suite of demonstration applications that will demonstrate the power of the Raspberry Pi. More on that in a future post.

So what compromises did we make?

Honestly? Not really that many.

The HDMIPi screen gives us 1280×800 resolution, plenty for hacking.

Our power supply gives around 5 hours of continuous use (under stress test)

To use the GPIO we had to use the Black HAT Hacker, a compromise yes but a great product that can be used to investigate the behavior and debug your favorite add on boards.

We did have to compromise on a wired keyboard and mouse, due to a few issues with the still buggy Bluetooth card used on the Raspberry Pi 3 preventing the use of our Rapoo E6700, for now at least.

So now we have the kit to help our Dynamic Duo in their travels across the UK!