Build an ultrasonic tape measure with an Arduino
analog-to-digital converter (ADC) on-board, but this can be added cheaply with a $5 Arduino board and its built-in 10-bit ADC. Further, plug in that HC-05 Bluetooth module into the Arduino board and you can have it working wirelessly on a smartphone or Pi 3.
3 MULTIMEDIA
Given many Raspberry Pi boards have ended up powering home theatre systems, it’d be wrong not to also consider the multimedia capabilities from an Android mini-PC perspective. To be fair, the lack of HDMI on a budget smartphone definitely limits the appeal in that regard. But having a built-in screen and battery gives it other options the Pi 3 doesn’t have.
Unfortunately, the Alcatel Pixi 3 (4.5) also lacks built-in Miracast or ‘screen casting’, meaning you can’t transmit the screen contents over Wi-Fi to another display device. However, it has one saving grace — and that is it works happily with a Chromecast dongle. Use the phone as a remote control and you can access your own media content or head online and watch YouTube, Netflix or Stan movies and TV shows. And of course, you can always watch your own content — whether stored locally or on your own home network — on the device screen itself.
4 ROOT ACCESS
One of the things that always surprised us about the Raspberry Pi has been the lack of Android support. Not long after the original launch, an effort began in porting Android 4.0 to the first-gen Pi, there were even a couple of screenshots floating around. But unfortunately, that’s as far as it got, as support for Linux distros, in particular the brilliant ‘Raspbian’, took off. However, one of the more interesting rumours doing the rounds recently is that an official Android could soon be coming to the Raspberry Pi 3. Google has indeed added the latest Pi 3 board as a new device tree in the Android Open Source Project (AOSP) repository ( tinyurl.com/apc432andpi), but at time of writing, the tree folder was as empty as a pub with no beer. Given it was Google’s Eric Schmidt who gave the Raspberry Pi Foundation’s
“One of the things that always surprised us about the Raspberry Pi has been the lack of Android support.”
Eben Upton the nudge to launch the US$5 Raspberry Pi Zero, an Android distro for the Pi 3 wouldn’t surprise.
In the meantime, the first thing we’d suggest doing with any Android mini-computer, provided you don’t mind some risk and losing your warranty, is gaining root access. That said, doing so on the Alcatel Pixi 3 (4.5) requires not the most-complex process ever devised, but we reckon it wouldn’t be far off!
The process is outlined over at XDA Developers and isn’t without risk, but here it is in a nutshell: first, you need special VCOM preloader drivers for the MediaTek MT6735M CPU — the drivers aren’t signed so installing on anything 64-bit after Windows 7 is a pain. You also need the MediaTek SP Flash Tool to flash the new Recovery ROM to the device. Next, you need an actual Recovery ROM. TeamWin Recovery Project (TWRP) is recommended, but don’t use the new 3.0.0-0 release — it doesn’t work on the Pixi 3 (4.5). Get the ‘TWRPRecovery4G’ ROM and full details from tinyurl.com/apc431-twrp listed in Point 5 on the webpage. You also need SuperSU from XDA guru Chainfire. Stick all of it in a blender and, eventually, you’ll get root access.
32GB WIRELESS SERVER
The benefit of having root access is that you gain full control of your device, rather than just the bits of the Android operating system Google would prefer you stick to. In fact, one of the things you can do with root access is to turn your Android device into an emergency wireless file server. We’ve looked at this a couple of times previously, so just briefly, you can turn a rooted Pixi 3 (4.5) into a 32GB wireless file server, accessible from any device on your home network. All you need is to purchase and install SambaDroid Pro from Google Play (there is a free version to try out first). You can set password and folder restrictions — and it’s more than fast enough to stream video files. Most NAS boxes have less CPU power than you’ll find inside the Pixi 3 (4.5) anyway.
THERE’S MORE BEYOND THE BOX
As we’ve said before, the Raspberry Pi concept is brilliant as a stepping stone into a larger world of technology. But it’d be a shame if the Raspberry Pi was as far as you got. The world of electronics (and we’re talking right up to computers and smartphones) is jam-packed with millions of different options for doing almost anything.
You could start by learning about the $5 Arduino, then the components behind Arduino-like boards — microcontrollers from Atmel and Microchip, among others. Delve down into the microcontroller chips themselves and learn how different types of transistors work, from common bipolar-junction transistors or BJTs to metal-oxide silicon fieldeffect transistors or MOSFETs.
The Raspberry Pi is a brilliant tool for learning — no question. But as the cost of computing in all its forms continues to fall, the Pi isn’t the only low-cost computer going around. You might just find an alternative at your local supermarket.
“You could start by learning about the $5 Arduino, then the components behind Arduino-like boards.”