I’ve written before about the usefulness of the (now sadly discontinued) Motorola Lapdock as a screen and keyboard/touchpad interface for the Raspberry Pi.
This week I’ve been playing with the Mk802 Android 4.0 PC – which is an ultra cheap A10 Arm powered computer on a stick, and have discovered it works nicely with the lapdock to make a portable Android laptop. You can pick up one of these versatile sticks for about £40 available from amazon or ebay, although you might need to hunt around for the lapdock as they’re now increasing in price (I was lucky to get one for £50 – I’d suggest ebay or looking for one with a non-english keyboard).
The Android 4 PC came with a US 5v power adapter but there’s no need to use it – you can power the mini PC via the mini USB port on the side – presumably if you want to use this with a TV which has a powered USB port you can use the same method.
I used the cable adapter I originally put together for my Raspberry Pi – this converts the micro HDMI on the lapdock to normal HDMI (the android stick has a mini HDMI in so an additional adapter was required) and splits the lapdock micro USB to USB power-only and USB data-only cables. For added convenience there’s a power switch to click the Mini PC on and off – which is handy as the lack of a power switch is one of the Mini PC’s criticisms.
The setup above is slightly unwieldy as I built the original adapter to fit the Raspberry Pi, but the Mini PC stick itself is very small and light so it doesn’t but a lot of strain on the connectors on the dock itself. There’s a wiring diagram on my original blog post along with a list of parts. It would be quite easy to lighten the assembly above with thinner cables – I kept the original USB female connector to make the adapter more versatile.
All together the resulting Android 4 tablet isn’t bad:
The lapdock’s keyboard is recognised – keys like function-home work and I’ve not encountered any mapping errors. You can also adjust the volume with the keyboard hot keys. The only drawbacks I can see is that all sound comes through the speakers – the lapdock lacks a headphone out socket - and the overscan adjustment doesn’t quite work – there’s a narrow black border around the screen, although fullscreen video playback works right up to the edges.
The android laptop works well with most of the apps I’ve run with it – the play store is installed by default although google reports it as an ‘unrecognised device’. Some 3d apps don’t work and I imagine other more complicated apps might struggle with the single core 1.5ghz processor – but it does run angry birds.
It is also possible to hack the android mini pc to run other operating systems like Ubuntu – and to upgrade it to android 4 jelly bean, as well as adding support for bluetooth which might solve the headphones issue. It’s not going to replace my Raspberry Pi as an experimental mini PC any time soon, but as a handy web-browser and media player that I can chuck in a bag it’s quite handy.