Custom PC, Issue 151

Custom PC Issue 151In my latest Hobby Tech column for Custom PC, I take a look at the Pi Zero-specific pHAT family of add-on boards from local electronics wizards Pimoroni, review the Guitar computer-on-module from China’s LeMaker, and show readers how to enhance a Raspberry Pi with a simple reset-stroke-power switch.

Firstly, the pHATs. The launch of the Raspberry Pi Zero, reviewed in last month’s Hobby Tech, brought with it the opportunity for Pi experts like Pimoroni to come out with some add-on devices matching the same form factor – which is, unsurprisingly, exactly what the company has done. The result is a family of, at the time of the review, three tiny add-on boards: the Explorer pHAT, Scroll pHAT, and pHAT DAC. Each comes with unpopulated GPIO, giving the user the option of soldering on the bundled female header for the ability to easily remove the device or soldering it directly to a Pi Zero to make an ultra-compact electronic sandwich.

The Explorer pHAT is the most versatile of the bunch, adding 5V outputs, inputs, analogue inputs, and even a pair of motor control channels to the Pi’s otherwise feature-light 3.3V GPIO header. The Scroll pHAT, meanwhile, features some bright white LEDs in a 5×11 matrix and comes with software for scrolling messages. Finally, the pHAT DAC is an ultra-compact digital to analogue converter capable of playing back 192KHz 24-bit audio via a pre-fitted 3.5mm jack or optional pair of RCA jacks. In short: there’s a little something for everyone.

The Guitar is LeMaker’s follow-up device to what was previously known as the Banana Pi – and, like its predecessor, LeMaker is taking design cues from the Raspberry Pi Foundation. This time, it’s made a Compute Module-alike: a small SODIMM-layout computer-on-module which comes bundled with a break-out board to access its various features. Considering the high price of the official Compute Module, I had high hopes for the budget-friendly Guitar – and I’m pleased to say that it mostly didn’t disappoint.

Finally, the reset switch tutorial. A variant of the tutorial I prepared for The MagPi tailored specifically to the Custom PC audience, it walks the reader through adding a simple switch to any Raspberry Pi – but focusing on the new Zero – in order to quickly reset the device in the event of a crash. As an added bonus, it also allows you to power the Pi on from a shut-down state.

All this, plus a bunch of stuff written by people other than me, can be yours in Custom PC Issue 151. Either pick up a physical copy from wherever magazines congregate, or snag it digitally via Zinio or similar distribution services.